5 àc.

HARVARD UNIVERSITY

«

Library of thè

Museum of

Comparative Zoology

della Società Italiana

di Scienze Naturali

e del Museo Civico

Volume XXVII - Fascicolo I di Storia Naturale di Milano

Biology as History

Papers from International Conferences sponsored by thè

California Academy of Sciences in San Francisco and thè

Museo Civico di Storia Naturale in Milan

.

N. 1

Systematic Biology as an Historical Science

Milano, 24-26 June 1993

Edited by Giovanni Pinna and Michael Ghiselin

MILANO 29 MARZO 1996

Elenco delle Memorie della Società Italiana di Scienze Naturali

e del Museo Civico di Storia Naturale di Milano

Volume I

I - Cornalia E., 1865 - Descrizione di una nuova specie del

genere Felis: Felis jacobita (Corn.), 9 pp., 1 tav.

II - Magni-Griffi F., 1865 - Di una specie d 'Hippolais nuova

per l’Italia, 6 pp., 1 tav.

Ili - Gastaldi B., 1865 - Sulla riescavazione dei bacini lacustri

per opera degli antichi ghiacciai. 30 pp., 2 figg., 2 tavv.

IV - Seguenza G., 1865 - Paleontologia malacologica dei ter¬

reni terziarii del distretto di Messina. 88 pp., 8 tavv.

V - Gibelli G., 1865 - Sugli organi riproduttori del genere

Verrucaria, 16 pp., 1 tav.

VI - Beggiato F. S., 1865 - Antracoterio di Zovencedo e di

Monteviale nel Vicentino, 10 pp., 1 tav.

VII - Cocchi I., 1865 - Di alcuni resti umani e degli oggetti di

umana industria dei tempi preistorici raccolti in Toscana.

32 pp., 4 tavv.

Vili - Targioni-Tozzetti A., 1866 - Come sia fatto l’organo che

fa lume nella lucciola volante dell’Italia centrale ( Luciola

italica ) e come le fibre muscolari in questo ed altri Insetti

ed Antropodi. 28 pp., 2 tavv.

IX - Maggi L., 1865 -Intorno al genere Aeolosoma. 18 pp., 2 taw.

X - Cornalia E., 1865 - Sopra i caratteri microscopici offerti

dalle Cantaridi e da altri Coleotteri facili a confondersi

con esse. 40 pp., 4 tavv.

Volume II

I - Issel A., 1866 - Dei Molluschi raccolti nella provincia di

Pisa, 38 pp.

II - Gentilli A., 1866 - Quelques considérations sur l’origine

des bassins lacustres, àpropos des sondages du Lac de

Come. 12 pp., 8 tavv.

III - Molon F., 1867 - Sulla flora terziaria delle Prealpi venete.

140 pp.

IV - D’Achiardi A., 1866 - Corollarj fossili del terreno num-

mulitico delle Alpi venete. 54 pp., 5 tavv.

V - Cocchi I., 1866 - Sulla geologia dell’alta Valle di Magra.

18 pp., 1 tav.

VI - Seguenza G., 1866 - Sulle importanti relazioni paleonto¬

logiche di talune rocce cretacee della Calabria con alcuni

terreni di Sicilia e deH’Africa settentrionale. 18 pp., 1 tav.

VII - Cocchi I., 1866 - L’uomo fossile nell’Italia centrale. 82 pp.,

21 figg., 4 tavv.

Vili - Garovaglio S., 1866 - Manzonia cantiana, novum Liche-

num Angiocarporum genus propositum atque descriptum.

8 pp., 1 tav.

IX - Seguenza G., 1867 - Paleontologia malacologica dei ter¬

reni terziarii del distretto di Messina (Pteropodi ed Etero-

podi). 22 pp., 1 tav.

X - Durer B., 1867 - Osservazioni meteorologiche fatte alla

Villa Carlotta sul lago di Como, ecc. 48 pp., 11 tavv.

Volume III

I - Emery C., 1873 - Studii anatomici sulla Vipera Redii. 16 pp.,

1 tav.

II - Garovaglio S., 1867 - Thelopsis, Belonia, Weitenwebera

et Limboria, quatuor Lichenum Angiocarporum genera reco-

gnita iconibusque illustrata. 12 pp., 2 tavv.

Ili - Targioni-Tozzetti A., 1867 - Studii sulle Cocciniglie.

88 pp., 7 tavv.

IV - Claparède E. R. e Panceri P., 1867 - Nota sopra un Alcio-

pide parassito della Cydippe densa Forsk. 8 pp., 1 tavv.

V - Garovaglio S., 1871 - De Pertusariis Europae mediae com¬

mentano. 40 pp., 4 tavv.

Volume IV

I - D’Achiardi A., 1868 - Corollarj fossili del terreno num-

mulitico dell’ Alpi venete. Parte II. 32 pp., 8 tavv.

II - Garovaglio S., 1868 - Octona Lichenum genera vel adhuc

controversa, vel sedis prorsus incertae in systemate, novis

descriptionibus iconibusque accuratissimis illustrata. 18 pp.,

2 tavv.

Ili - Marinoni C., 1868 - Le abitazioni lacustri e gli avanzi di

umana industria in Lombardia. 66 pp., 5 figg., 7 tavv.

IV - (Non pubblicato).

V - Marinoni C., 1871 - Nuovi avanzi preistorici in Lombar¬

dia. 28 pp., 3 figg., 2 tavv.

NUOVA SERIE

Volume V

I - Martorelli G., 1895 - Monografìa illustrata degli uccelli

di rapina in Italia. 216 pp., 46 figg., 4 taw.

Volume VI

I - De Alessandri G., 1897 - La pietra da cantoni di Rosi-

gnano e di Vignale. Studi stratigrafici e paleontologici.

104 pp., 2 tavv., 1 carta.

II - Martorelli G., 1898 - Le forme e le simmetrie delle

macchie nel piumaggio. Memoria ornitologica. 112 pp.,

63 figg., 1 tavv.

Ili - Pavesi P., 1901 - L’abbate Spallanzani a Pavia. 68 pp., 14 figg.,

1 tav.

Volume VII

I - De Alessandri G., 1910 - Studi sui pesci triasici della

Lombardia. 164 pp., 9 tavv.

Volume Vili

I - Repossi E., 1915 - La bassa Valle della Mera. Studi petro-

grafici e geologici. Parte I. pp. 1-46, 5 figg., 3 tavv.

II - Repossi E., 1916 (1917) - La bassa Valle della Mera. Studi

petrografici e geologici. Parte IL pp. 47-186, 5 figg., 9 tavv.

Ili - Airaghi C., 1917 - Sui molari d’elefante delle alluvioni

lombarde, con osservazioni sulla filogenia e scomparsa di

alcuni Proboscidati. pp. 187-242, 4 figg., 3 tavv.

Volume IX

I - Bezzi M., 1918 - Studi sulla ditterofauna nivale delle Alpi

italiane, pp. 1-164, 7 figg., 2 tavv.

II - Sera G. L., 1920 - Sui rapporti della conformazione della

base del cranio colle forme craniensi e colle strutture della

faccia nelle razze umane. - (Saggio di una nuova dottrina

craniologica con particolare riguardo dei principali cranii

fossili), pp. 165-262, 7 figg., 2 tavv.

Ili - De Beaux O. e Festa E., 1927 - La ricomparsa del Cin¬

ghiale nell’Italia settentrionale-occidentale, pp. 263-320,

13 figg., 7 tavv.

Volume X

I - Desio A., 1929 - Studi geologici sulla regione dell’Albenza

(Prealpi Bergamasche), pp. 1-156, 27 figg., 1 tav., 1 carta.

II - Scortecci G., 1937 - Gli organi di senso della pelle degli

Agamidi. pp. 157-208, 39 figg., 2 tavv.

Ili - Scortecci G., 1941 - 1 recettori degli Agamidi. pp. 209-326,

80 figg.

Volume XI

I - Guiglia D., 1944 - Gli Sfecidi italiani del Museo di Mila¬

no ( Hymen .). pp. 1-44, 4 figg., 5 tavv.

II-III- Giacomini V. e Pignatti S., 1955 - Flora e Vegetazione

dell’Alta Valle del Braulio. Con speciale riferimento ai

pascoli di altitudine, pp. 45-238, 31 figg., 1 carta.

Volume XII

I - Vialli V., 1956 - Sul rinoceronte e l’elefante dei livelli

superiori della serie lacustre di Leffe (Bergamo), pp. 1-70,

4 figg., 6 tavv.

II - Venzo S., 1957 - Rilevamento geologico dell’anfiteatro

morenico del Garda. Parte I: Tratto occidentale Gardone-

Desenzano. pp. 71-140, 14 figg-, 6 tavv., 1 carta.

Ili - Vialli V., 1959 - Ammoniti sinemuriane del Monte

Albenza (Bergamo), pp. 141-188, 2 figg., 5 tavv.

Volume XIII

I - Venzo S., 1961 - Rilevamento geologico dell’anfiteatro

morenico del Garda. Parte IL Tratto orientale Garda-Adi-

ge e anfiteatro atesino di Rivoli veronese, pp. 1-64, 25 figg.,

9 tavv., 1 carta.

II - Pinna G., 1963 - Ammoniti del Lias superiore (Toarciano)

dell’Alpe Turati (Erba, Como). Generi Mercaticeras, Pseu-

domercaticeras e Brodieia. pp. 65-98, 2 figg., 4 tavv.

Ili - Zanzucchi G., 1963 - Le Ammoniti del Lias superiore

(Toarciano) di Entratico in Val Cavallina (Bergamasco

orientale), pp. 99-146, 2 figg., 8 tavv.

Biology as History

Papers from International Conferences sponsored by thè

California Academy of Sciences in San Francisco and thè

Museo Civico di Storia Naturale in Milan

UNlV£^ir

N. 1

Systematic Biology as an Historical Science

Milano, 24-26 June 1993

Edited by Giovanni Pinna and Michael Ghiselin

Volume XXVII - Fascicolo I

29 marzo 1996

Memorie della Società Italiana di Scienze Naturali

e del Museo Civico di Storia Naturale di Milano

Museo Civico di Storia Naturale di Milano

corso Venezia, 55 - 20121 Milano

Registrato al Tribunale di Milano al n. 6694

Direttore responsabile: Giovanni Pinna

Segretaria di redazione: Anna Alessandrello

Redazione: Magda Lusiardi, Marcello Michelangeli

Grafica editoriale Michela Mura

Stampa Tipografia Solari, Peschiera Borromeo - marzo 1996

ISSN 0376-2726

Workshop on Systematic Biology

as an Historical Science

3

PROGRAM

Thursday June 24th

9,00 Welcome address by Giovanni Pinna, Direc¬

tor of thè Museo di Storia Naturale di Milano

Morning Session

Chairman: David B. Wake

9,30 Alberto Simonetta (Università di Camerino):

Systematics: is an historical perspective use-

ful to understand modern debates on syste¬

matics and are we really equipped for sound

evolutionary systematics?

11,00 Alessandro Minelli (Università di Padova):

Some thought on homology 150 years after

Owen’s definition.

12,00 Robert J. O’Hara (University of North Carol¬

ina at Greensboro): Trees of history in syste¬

matics and philology.

Afternoon Session

Chairman: Michael T. Ghiselin

15.30 David B. Wake (University of California, Ber¬

keley): Schmalhausen’s evolutionary mor-

phology and its value in formulating research

strategies.

17,00 James R. Griesemer (Wissenschaftskolleg zu

Berlin): Some concepts of historical Science.

18.30 Opening of thè exhibition «Haeckel e l’Italia»

at thè Museo di Storia Naturale

Friday June 25th

Morning Session

Chairman: Adam Urbanek

9,30 Michael T. Ghiselin (California Academy of

Sciences, San Francisco): Charles Darwin,

Fritz Miiller, Anton Dohrn, and thè origin of

evolutionary physicological anatomy.

11,00 Francesco Scudo (IGBE-CNR, Pavia): Sym-

biosis, thè origins of major life forms and sys¬

tematics: a review with speculations.

12,00 Mikhail A. Fedonkin (Russian Academy of

Sciences, Moscow): The Precambrian fossil

record: new insight of life.

Afternoon Session

Chairman: Cesare Baroni Urbani

15.30 Adam Urbanek (Polska Akademia Nauk,

Warsaw): The origin and maintenance of

diversity: a case study of Upper Silurian

graptoloids.

17,00 E. Nicholas Arnold (The Naturai History

Museum, London): The role of biological

process in phylogenetics with examples from

thè study of lizards.

Saturday June 26th

Morning Session

Chairman: Francesco Scudo

9,00 Yves Bouligand (Institute de Biologie Théo-

rique, Angers): Morphological singularities

and macroevolution.

10.30 Eugene Presnov (The Weizmann Institute of

Science, Rehovot): Topological classifìca-

tion: onto- and phylogenesis.

11.30 René Thom (Institute des Hautes Études

Scientifiques, Bures-sur-Yvette): Quali¬

tative and quantitative in Evolutionary

Theory with some thoughts on Aristotelian

Biology.

4

LIST OF PARTICIPANTS

Giovanni Pinna

Museo Storia Naturale

Corso Venezia 55

20121 Milano, ITALIA

Eugene Presnov

The Weizmann Institute of Science

Department of Applied Mathematics

Rehovot 76100, ISRAEL

Francesco M. Scudo

IGBE (CNR)

Via Abbiategrasso 207

27100 Pavia, ITALIA

Alberto M. Simonetta

Dipartimento di Biologia

Università degli Studi di Camerino

Via F. Camerini 2

62032 Camerino, ITALIA

E. Nicholas Arnold

British Museum (Naturai History)

Cromwell Road

London SW7 5BD, ENGLAND

Cesare Baroni Urbani

Zoologische Institute

Rheinspung 9

4051 Basel, SUISSE

Yves Bouligand

Institute de Biologie Téorique

10, rue André - Bocquel

49000 Angers, FRANCE

Mikhail A. Fedonkin

Paleontological Institute

Russian Academy of Sciences

Profsoyuznaya ul. 123

Moscow 117647, RUSSIA

Michael T. Ghiselin

Center for thè History and Philosophy of Science

California Academy of Sciences

Golden Gate Park

San Francisco, Ca 94118-4599, USA

James R. Griesemer

Wissenschaftskolleg zu Berlin and

University of California

Dep. of Philosophy

Davis, CA 95616-8673, USA

Alessandro Minelli

Dipartimento di Biologia

Università di Padova

Via Trieste 75

35121 Padova, ITALIA

Robert J. O’ Hara

Cornelia Strong College and Dep. of Biology

100 Foust Building,

Univ. of North Carolina at Greensboro

Greensboro, NC 27412-5001, USA

René Thom

Institute des Hautes Etudes Scientifìques

91440 Bures sur Yvette, FRANCE

Adam Urbanek

Instytut Paleobiologii PAN

Al. Zwirki i Wigury 93

02-089 Warsaw, POLAND

David B. Wake

Dep. of Integrative Biology and

Museum of Vertebrate Zoology

University of California

Berkeley, Ca 94720, USA

5

Cari colleghi

solo due parole per ringraziarvi di aver accettato di

partecipare a questo workshop on Systematic Biolo-

gy as an Historical Science, organizzato dal Museo di

Storia Naturale di Milano e dalla California Acade-

my of Sciences, e per presentarvi il nostro Museo.

Il Museo di Storia Naturale di Milano è un museo

che, sebbene appartenga alla Città di Milano, è tutta¬

via il maggiore museo italiano di Storia Naturale.

Fondato nel 1938, prima dell’unità d’Italia, il

museo ha avuto una lunga storia scientifica; in esso

hanno operato alcuni noti studiosi italiani di ogni

campo delle scienze naturali, che con le loro ricerche

hanno fatto conoscere il museo anche al di fuori dei

confini d’Italia.

Nel 1943 il Museo è stato completamente distrutto

durante un bombardamento aereo, perdendo tutte le

sue collezioni. Tutto ciò che oggi è presente nelle

esposizioni e nelle collezioni scientifiche del museo

è dovuto quindi all’opera di ricostruzione portata

avanti con tenacia dalla città di Milano.

Oggi il Museo è in fase di ristrutturazione: si sta

cioè operando per costruire un’esposizione più mo¬

derna e più informativa di quella realizzata frettolo¬

samente negli anni 50, e che permise la riapertura al

pubblico del museo dopo solo 7 anni dalla distruzio¬

ne completa dell’edificio.

Prima di cedere la parola a David Wake, modera¬

tor di questa prima sessione del workshop, vorrei rin¬

graziare Michael Ghiselin e Francesco Scudo, che

hanno svolto una parte fondamentale nell’organizza¬

zione scientifica del workshop.

Spero che avrete un buon soggiorno a Milano e

tengo a precisare che le condizioni metereologiche

non dipendono dall’organizzazione.

Ladies and gentlemen

Only a few words thanking you for your presence

at this workshop on Systematic Biology as an Histo¬

rical Science organized by thè Museo di Storia Natu¬

rale di Milano and thè California Academy of Scien¬

ces and introducing you our Museum.

The Museo di Storia Naturale di Milano, though

depending on thè Municipality of Milan, is however

thè most important Italian Museum of Naturai His-

tory.

Founded in 1838 before thè Italian unifìcation, it has

a long scientific history: here worked several well

known italian scientists, whose researches in thè dif-

ferent fìelds of naturai history let know thè Museum

also outside thè Italian borders.

During 1943 thè Museum was totally destroyed by

an air-bombardment, losing all its collections. All

what is now present in thè exhibitions and in thè

scientifical collections of thè Museum is therefore

due to thè reconstruction work tenaciously pursued

by thè city of Milan.

Nowadays thè Museum lives a phase of rearrange¬

ment, that is we are working to prepare up-to-date

exhibitions offering more informations than those

hastily carried out during thè fìfties, which allowed

thè reopening to thè public only seven years after thè

total destruction of thè building.

Before calling on David Wake, moderator of

this fìrst session, I am glad to thank Michael Ghi¬

selin and Francesco Scudo, who played a funda-

mental role in thè scientific organization of this

workshop.

I hope you will have a nice stay in Milan, and I

would like to specify that wheather conditions don’t

depend on thè organization.

Giovanni Pinna

Fig. 1 - The participants to thè Milano workshop. High up, from left: Alberto Simonetta, Michael Ghiselin, James Griese-

mer, Alessandro Minelli, Nicholas Arnold, Robert O’Hara, René Thom, Eugene Presnov, David Wake; below, from left:

Giovanni Pinna, Yves Bouligand, Cesare Baroni Urbani, Adam Urbanek, Francesco Scudo, Mikhail Fedonkin.

'

:

■

Systematic biology as an historical Science

discussion and retrospect

by Michael T. Ghiselin

Because thè Milan conference was an informai

gathering it did not seem appropriate to publish com-

mentary by discussants. Instead thè authors were en-

couraged to incorporate what had been said when

they revised their manuscripts. A decision was also

made to prepare a statement that would provide

for some synthesis of thè results. Ghiselin wrote a

draft, based upon thè commentary from thè sessions

and additional materials solicited from thè partici-

pants. It was then circulated among thè participants,

revised in thè light of their suggestions, and is pre-

sented here.

The intent of thè organizers (Pinna, Scudo, Ghise¬

lin) was to investigate some alternatives to thè kind

of phylogenetics that has recently become fashion-

able. The emphasis has been almost entirely upon

cladograms and very little attention has been paid to

phylogenetics in thè sense of historical narrative.

The very legitimacy of such an alternative has been

seriously questioned. However, thè intent of thè par¬

ticipants was by no means to reject thè advances in

cladistic techniques that have become established in

thè past thirty years. It was a question of addition,

not subtraction.

As someone who considers himslef a cladist,

O’Hara expressed thè opinion that opposition to nar¬

rative history and a broader range of evidence is be-

coming more and more a thing of thè past, at least

among younger workers. Simonetta, urged that thè

emphasis should be upon thè questions raised, ra-

ther than upon particular answers. Minelli pointed

out that narrative history is but one example of top-

ics that have been underemphasized — especially

comparative functional anatomy.

The diversity of thè participants would probably

preclude altogether any affort to found a new school

of systematic biology. But their very diversity

brought out how much opportunity has been ne-

glected. If there was any unanimity about anything it

was that lack of communication has been a serious

problem. Work that might interest a wide range of

systematists has frequently been known only to spe-

cialists in particular taxa, and thè problem has been

exacerbated by linguistic barriers. As O’Hara stres-

sed, thè work of systematists has much in common

with a wide range of historical Sciences. Furthermo-

re, several of thè participants have been seriously in-

terested in thè history of biology, and their presenta-

tions made it abundantly clear that a great deal of

older work deserves more attention.

If any of thè participants felt that philosophy is un-

important, they certainly did not give that impres-

sion. There were lively discussions about all sorts of

philosophical issues, ranging from logicai matters

with respect to thè defìnition and use of terms to thè

very foundations of metaphysics. For example,

Thom suggested that thè digestive tract is really out-

side of thè organism. Some of thè biologists (Minelli,

Simonetta, Ghiselin), while acknowledging that this

suggestion is legitimate from a topological pint of

view, felt that it creates problems from thè physiolo-

gical point of view, especially when applied to vari-

ous body cavities (such as thè coelom being external

in human females but internai in human males). The

perennial discussion with respect to homology con-

cepts cropped up with respect to «incomplete» ho¬

mology (Urbanek). Arnold even went so far as to

wonder out loud whether this term has been so va-

guely defìned as to warrant our abandonig it!. There

was also some discussion about thè appropriateness

of other terms, for example, should we cali a lineage

that results from fusion of one or more independent

lineages «polyphyletic»?

There was deflnitely no consensus with respect to

such topics as thè relative importance of form and

function or pattern and process. The extreme diffe-

rence of opinion might be summed up by saying that

Thom supported thè tradition of Pythagorus and

Plato, Ghiselin that of Heraclitus, and Simonetta

that of thè nominalists. Griesemer extended this dis¬

cussion by suggesting that process indeed deserves

more attention, and it is not adequately understood

either in developmental biology or in thè study of

how scientists do research. Wake raised thè issue of

whether heterochrony is pattern or process, and sug¬

gested that perhaps it is pattern at a taxonomic level,

a notion opposed by Scudo on thè grounds that de-

velopment has to be a process.

Evolution, of course, is a process, but as Baroni-

Urbani pointed out, there is serious question of how

much evolution, if any, systematists really need

when doing their work. One of thè main reasons

for holding thè meeting was to address that parti¬

cular issue. Nobody carne out in favor of «pattern

cladism» and maintained that systematists do not

need evolution at all. On thè other hand it seem unli-

kely that any of thè participants will ever cali them-

selves «process cladists» - whatever that might

mean.

Presnov’s paper treated thè evolution of echino-

derms using purely topological characters, and there-

fore invoked only pattern. That this was a very inter-

esting exercise was not disputed, and Ghiselin, who

has done some research on echinoderm phylogenet¬

ics, opined that thè results seemed quite reasonable

given thè characters that were used and that they

could be supported by additional evidence. But he

argued that he could have done thè same job without

translating thè anatomy into topological language.

Scudo said that thè views of Presnov and Thom are

8

MICHAEL T. GHISELIN

theoretically interesting, but that thè practical signi-

ficance is uncertain.

The metaphysical issue of thè ontological status of

taxa, including thè proposai that species are indivi-

duals rather than classes, was not a major subject for

debate. It did surface, in a sense, when Thom sug-

gested that taxa are extensional sets and Ghiselin

responded that they are composite wholes, which

might better be treated with mereology rather than

with set theory; they concluded that this was not thè

appropriate solution. Thom had asked about thè tree

of Porphyry, and O’Hara responded that there are

important differences when we use a tree-like dia-

gram to represent thè relationships between abstrac-

tions such as kinds of furniture on thè one hand, and

historical entities connected by community of desc-

ent on thè other.

The ontological notion of thè individuality of spe¬

cies and clades (which, incidentali, Simonetta does

not accept) relates to thè epistemological issues

that surround thè role of laws of nature in historical

inference. Laws of nature are generalizations about

classes of individuals, and if taxa such as species are

individuals rather than classes, it follows that laws of

nature are not about taxa and thè generalizations that

systematists formulate about them are purely descrip-

tions of contigent, historical fact. The principle of uni-

formitarianism in geology works because thè laws of

nature do not change. But since taxa evolve we can-

not legitimately extrapolate to thè past on thè basis

of features shared by all extant members of a group.

As Griesemer explains in his article, there has

been a lot of discussion among philosophers of

Science as to whether thè historical Sciences are

Sciences at all. By defming «Science» in thè appropri¬

ate way, one can exclude such things as astronomy

and mammalogy from thè Sciences altogether. Tradi-

tional philosophy of Science has at least tended to

downgrade history, including naturai history, to an

inferior status. And this makes a great deal of sense,

since physicists founded thè movement and natural-

ly placed themnselves at thè top of thè academic

pecking order.

But historical Sciences, including not just zoology

and geology, but astronomy as well, present more

than just descriptive matters of fact about individuals

such as thè human species or thè sun. O’Hara sug-

gests that a distinction made by philosophers of his¬

tory might be useful in this respect. Chronicle is a

simple listing of events, whereas history proper is an

explanatory account of suche events. As Griesemer

points out, there are serious questions among philo¬

sophers of Science with respect to thè logie of histori¬

cal explanation and inference, especially thè role of

laws of nature. Ghiselin in commenting on Fedon-

kin’s contribution observed that in stratigraphic geo¬

logy there are generally accepted and uncontrover-

sial methodologies for establishing which event

Comes fìrst on thè basis of physical laws and princi-

ples, whereas in phylogenetics analogous modes of

inference are often rejected.

The question naturally arises of what kinds of laws

of nature or generai principles might be used in thè

reconstruction of thè history of life. There was gen¬

erai support of thè analysis of embryology, but of

course there have been a wide variety of embryolo-

gical approaches to phylogenetics and other evolu-

tionary studies. Darwin’s application of what carne

to be called developmental mechanics to phyloge-

netic inference fits in quite well with mainstream

evolutionary biology and there would seem to be no

good reason to accept thè claims of «Structuralists»

that some kind of paradigm shift that eschews thè

theory of naturai selection is in order (Wake, Minel-

li, Ghiselin). Wake and Ghiselin discussed this topic

again after thè meeting, when thè question arose

of how to differentiate modern notions of develop¬

mental constraint from traditional orthogenesis.

And is there any reai distinction between Vavilov’s

«homologous series» and Darwin’s «analogous va-

riation»?

One topic that was not explicitly addressed during

thè sessions, but did emerge several times during in¬

formai discussions, was thè cruciai role of museums

in systematic biology. Because thè workshop was co-

sponsored by two institutions that combine research

with education, such issues were of more than just

academic interest. The generai public tends to think

of naturai history museums as something like art

museums, thè major role of wichich is to provide a

chance for people to look at things. Their cruciai role

in research is most inadequately appreciated. Griese¬

mer noted that museum displays are intended to

show a particular order, but that there is a distinct

gap between discourse and research. In meeting thè

demand for information about thè environment,

museums are reorganizing their public displays in a

manner that tends to divert attention from thè basic

mission of systematics.

Systematics is of course thè Science that speciali-

zes in biodiversity, and therefore it has a cruciai role

to play in efforts to cope with thè present crisis. Dur¬

ing conversation, however, Wake expressed some

concern about thè study of biodiversity being domi-

nated by ecologists, whose agenda is not necessarily

compatible with that of systematists. There is a dan-

ger that systematics will be downgraded to a kind of

Service function for ecology and that, in consequen-

ce, it will lose thè hard-won intellectual respectabil-

ity that derives from its fundamental contributions

to evolutionary biology.

The current prosperity of paleobiology exists lar-

gely be cause paleontologists were dissatisfied with

thè traditional role of their Science as thè «hand-

maiden of stratigraphy» and shifted thè emphasis to

matters of more generai intellectual signifìcance.

The Journal Paleobiology was established after a sym¬

posium on «Models in Paleobiology» held at thè

meeting at thè Geological Society of America on No-

vember 2, 1971, in a deliberate effort to break with

that tradition. The Milan workshop was convened

with similar goals in mind, but with an important dif-

ference. The problem is not so much a matter of

gaining autonomy for systematics, as it is of main-

taining that autonomy by thè continued exploration

of new ideas.

E. Nicholas Arnold

The role of biological process in phylogenetics

with examples from thè study of lizards

Abstract — Biological process (except sometimes ontogenetic change) is not considered in cladistic phylogeny recons-

truction using non-molecular characters, but such universal exclusion violates thè principle of parsimony. Simple charac-

ter pattern is often insuffìcient on its own to produce robust hypotheses of phylogeny, and extinction and congruence

among what are in fact non-ancestral resemblances can cause misleading results; consequently additional insights from

process are valuable. Process can be helpful in thè recognition of character States, character independence, sequence of

change in transformation series and among different characters, and in weighting, that is thè assessment of thè relative

lability of character States. The fact that suppositions about are sometimes wrong and that their inclusion perturbs thè

basic simplicity of thè cladistic approach are insuffìcient reasons for not considering them at all.

Weighting can be based on character compatibility, homoplasy in thè studied group and outside it, and evidence of

lability from trait variation and from possible selective interactions between organisms and thè environment. The case

for weighting is strongest when some or all these factors are correlated. Weighting is most appropriately used after thè esta¬

blishment of an initial cladistic pattern, to resolve conflicts in evidence, to asses robustness of phylogenetic hypotheses

and, in principle, to assess relative transition probabilities for maximum likelyhood treatments of data. An example of

weighting among lacertid lizards is given. Some of thè evolutionary assumptions involved in weighting are testable using

robust hypotheses of phylogeny based on character distribution alone and such tests can potentially provide some circums-

tantial evidence for thè ubiquity of naturai selection in evolution.

Inclusion of process in estimation of phylogenies can lead to circularity if thè latter are subsequently used to study

process itself. However, thè extent of this problem has been exaggerated: where circularity is a reai possibility, such studies

can be safely conducted on robust phylogenies based on character distribution alone or ones that have been customised by

removai of thè specific process considerations concerned.

Introduction

This paper considers some of thè possible roles of

biological process in reconstructing phylogenies. In

this context, process includes thè changes that occur

during ontogeny and thè genetic and epigenetic

mechanisms that produce them, functional interac¬

tions between traits constituting organisms, and

functional interactions between organisms and their

environment. Discussion will concentrate on non-

molecular data.

Over most of thè history of systematics, thè idea

that consideration should be confmed to characters

themselves would have seemed strange to most taxo-

nomists and information or at least assumptions

about process was often included. Thus Cesalpino

(1583) gave precedence to traits involved in repro¬

duction and nutrition and Cuvier and Darwin used

functional considerations in weighting characters

(Mayr, 1982; Darwin, 1859). In contrast, a wides-

pread view over thè past dozen years is that thè ap¬

propriate way to conduct systematic studies is to take

characters, recognise at some stage their derived Sta¬

tes and, giving these equal weight, produce thè most

parsimonious hierarchical pattern associating taxa in

terms of number of state changes (steps) involved.

At no stage are generai models of how evolution oc-

curs or, indeed any suppositions about evolutionary

process, allowed to impinge on thè production of this

pattern which can be used directly as a classification

and, merely by a change of viewpoint, as a hypoth-

esis of phylogeny. So, without any alteration, thè

hierarchy with least steps is assumed to represent

thè result of thè evolutionary process. It can then be

used as a basis for assessing models of evolution and

recognising particular evolutionary phenomena.

This cladistic view of systematics obviously has

great appeal and has been widely acknowledged

(Platnick, 1979, 1985a, 1985b; Farris, 1979, 1980,

1982, 1983, 1985; Eldridge and Cracraft, 1980; Nelson

and Platnick, 1981). In fact it has variants. What is

often termed pattern cladistics excludes any referen-

ce at all to evolution and its primary aim is to produ¬

ce a generai basis for systematics. In contrast, evolu¬

tionary cladistics incorporates thè assumption that

hierarchical structure is a result of descent with mo-

dification and phylogeny reconstruction is its prim¬

ary aim (see for example Hennig, 1966; De Queiroz

& Donaghue, 1990, for discussion). However, al-

though these variants are likely to sometimes differ

in thè results they produce, they share thè generai

features of cladistics and will be treated together

here, unless otherwise specified.

When views become conventional wisdom (Gal-

braith, 1957), they are less likely to be subjected to

criticai scrutiny. Consequently, thè claims of generai

systems, like cladistics, need to be re-examined from

time to time. In thè present context, this applies es-

pecially to thè supposition that thè most parsimoni¬

ous hierarchies of equally weighted characters are

thè best, or at least most appropriate, estimates of

phylogeny and that most biological process should

be rigorously excluded from their production. This

question will be addressed here, but not such mat-

ters as thè appropriateness of cladistic pattern as thè

basis of classification.

10

E. N. ARNOLD

Problems in using cladistic pattern as thè sole source

for phylogeny estimation

It is a substantial imaginative leap to think that ge-

nealogical history can be derived from thè distribu-

tion of current characters among species. It is not a

leap that systematists have always been willing to

make (for instance many members of thè pheneticist

school) and depends to some extent on how we be-

lieve, or rather hope, evolution generally has taken

place. For total reconstruction to be possible, suffìc-

ient new traits must be generated, speciation events

must be uncommon by comparison and parallelism,

convergence and reversai must not prevent or obscu-

re thè development of a hierarchical pattern of cha-

racter change. If this is not universally so, we will be

reduced at best to reconstructing areas of phylogeny

with very different degrees of certainty and some re-

gions not at all.

Looking at thè results of using cladistic pattern

alone, this rather pessimistic possibility seems to be

thè case. A few analyses of groups appear unequivo-

cal, with all relationships strongly supported by nu-

merous characters and little conflict in thè evidence,

and these can be accepted as they stand as robust hy-

potheses of phylogeny. But, in other cases, there may

be many alternative equally parsimonious Solutions

and even more that have only marginally fewer steps.

Furthermore thè level of character conflict may be

very high and alternative trees very different. Indeed

it is possible for cladograms without conflict to be

substantially misleading as estimates of phylogeny.

For instance, situations can be envisaged where

extinction turns what would otherwise be clear ho-

moplasies into apparent evidence of relationship

(Arnold, 1981) and this is demonstrable in reai

groups, for instance when fossils are excluded from

analysis of amniote relationships (Gauthier, Kluge &

Rowe, 1988).

Even without such confounding effects of extinc¬

tion or inadequate sampling there is no reason to

think a single most parsimonious hierarchy will al¬

ways represent genealogy, especially as other hypo-

theses may be scarcely less parsimonious. It is some-

times said that characters reflecting genealogy will be

hierarchically congruent, whereas homoplasious

ones will tend not be so (see for example Farris,

1969). However, it is not uncommon for competing

sets of congruent characters to exist (p. 000), indicat-

ing that homoplasy can be ordered. Finally parsimo-

ny analysis will produce trees from randomised data

and can therefore suggest pattern where none exists.

Randomisation (= permutation) tests (Archie, 1989

a,b; Faith, 1991; Faith & Cranston, 1991; Trueman,

1993) indicate that this is indeed often thè case with

reai data sets.

The cladistic approach to phylogeny reconstruc¬

tion may turn out to be thè best that can be achieved

but it frequently fails to produce robust results and it

is consequently appropriate to consider using addi-

tional sources of inference, such as ones derived

from biological process, if this can be justified. Alter-

natively, we might take refuge in thè hope that even¬

tuali additional characters will be found that enable

a robust hypothesis of phylogeny to be produced by

straightforward cladistic means. This may happen,

but it is not certain to occur and in itself is no reason

why other relevant evidence should be excluded.

Another problem concerns thè application of thè

principle of parsimony, that thè simplest solution

that thè evidence allows should be accepted. In cla-

distics, simplest is taken to mean thè version of

events involving thè least number of steps. However,

it can be argued that thè principle is not being pro-

perly applied (Arnold, 1981), for its use carries thè

proviso that all relevant evidence should be conside-

red before thè simplest solution is chosen. Clearly on

this basis, if biological process provides additional

indicators about thè way characters change these

should be taken into account.

In cladistics, so far as is possible, different charac¬

ters are considered to be potentially equal indicators

of relationship and changes between States equally

likely. This democratic approach, (Arnold, 1981), is

essentially a kind of weighting for which there is no

supporting evidence. It might possibly be justified by

thè statistical principle of indifference, that in thè ab-

sence of any reason to expect one event more than

another, they should all be assigned equal probabil-

ity as a matter of convenience (Keynes, 1921; Wilkin-

son, 1992). Certainly, there are situations where it is

necessary to work like this, but to raise such a prag-

matic working method to a rigid law of procedure,

prevents our ever investigating possible sources of

information that might enable us to assign different

probabilities to changes in States. In fact, cladistic

phylogeny estimation often involves tacit character

weighting of other kinds, either in processing charac¬

ters in particular ways, for instance treating multi-

state characters as either ordered or unordered or

eliminating characters on thè grounds of their varia-

bility (Piementel & Riggins, 1987).

Some arguments against incorporating process

Supporters of thè pattern-process dichotomy will

often point out that their System, in eschewing most

process, has thè advantages of universal applicability,

simplicity and clarity, for it is very obvious what is

being done. Universality of application is a virtue in a

method but not if it sometimes involves excluding

other sources of inference that might otherwise be

acceptable. In a country where vehicles are present

but rare, there is little sense in insisting people

should always walk merely because this method of

locomotion is always available. While every effort

must be made to achieve methodological clarity,

other sources of inference should not be excluded

on thè grounds that they complicate procedure.

Proponents of cladistic approaches also point to thè

efficiency of thè hierarchies produced in reflecting

information content but this does not necessarily in¬

dicate efficiency in reflecting phylogeny.

It is also stressed that it is easy to be wrong about

process as an indicator in classification and phyloge¬

ny reconstruction. This is certainly true: Cesalpino

was mistaken to believe that reproductive and nutri¬

tive structures of plants should be given precedence;

some of Manton’s (1977) arguments about thè poss¬

ible course of arthropod evolution based on limb and

jaw function have not been supported by other sour¬

ces of evidence. Although such cases are often em-

phasised, it must be remembered that cladistic pat-

terns and thè processes involved in producing them

are also subject to reappraisal in thè light of further

THE ROLE OF BIOLOGICA!. PROCESS IN PHYLOGENETICS

11

information, especially that derived from additional

characters and taxa. It is inappropriate to exclude

process indicators merely on thè grounds that they

are sometimes shown to be wrong; such exclusion is

only justificable if such factors can be shown to fre-

quently mislead. Tn phylogeny assessment, we are

dealing with situations of generai uncertainty: all evi-

dence is provisionai and this applies to thè results

too. The introduction of an additional set of faulted

indicators into a System where pre-existing indica¬

tors are also faulted does not necessarily decrease

overall reliability. Provided levels of failure are not

too high and thè new indicators are independent of

those already present, they are unlikely to often ge-

nerally reinforce errors associated with thè latter. In-

stead, they can provide valuable corroboration of

some hypotheses of relationships.

For a long time, knowledge of organisms was lar-

gely confmed to their morphology which was access-

ible through museum collections, while information

about other aspects was extremely sparse. In this sit-

uation, it was appropriate to concentrate on thè ana-

tomical features from which cladistic characters have

been customarily drawn and it is not surprising that

attempts to incorporate process were often clearly

unsuccessful. However, now so much more is known

about non-anatomical aspects of organisms, there is

a much stronger case for attempting to use such in¬

formation in phylogeny estimation and error is likely

to be more avoidable.

At first sight, a more cogent objection to thè use of

evolutionary process, is thè belief that including it in

phylogeny reconstruction will result in circularity if

such phylogenies are later used to study evolutionary

process itself. In actuality, evolutionary process has

many components and when studying one, thè fact

that other independent factors have been used in

producing thè phylogeny is immaterial. Furthermore

for most uses to which phylogenies are put no such

POSSIBLE ROLES FOR BIOLOGICAL PI

It would be a happy coincidence if producing a

hierarchical character distribution also automatically

produced a phylogeny as a bonus, but as we have

seen there is no reai reason to expect this will always

happen. This being so, it seems best to disengage any

automatic association of character hierarchy, classifì-

cation and phylogeny and aim for thè latter as such,

using whatever means are available including greater

consideration of biological process.

Process is relevant in at least four areas of phyloge¬

ny reconstruction: recognising and specifying differ-

ent character States, assessing character independen-

ce, determining order of state and character change

and deciding which derived character States are likely

to give more reliable evidence about relationships,

that is character weighting.

Recognition and specifìcation of States

Developmental studies sometimes show that fea¬

tures which are thè same in their final form often

have different early stages and this information can

be used to recognise additional different States of a

character (De Queiroz, 1985). Ontogeny can also in¬

dicate that a feature may be being misinterpreted.

circularity exists. When it does so, it should be elimi-

nated by modifying thè evidential base for thè phylo¬

geny when such a study is made. Essentially, we have

thè alternatives of often accepting a suboptimal esti¬

mate of phylogeny based entirely on pattern which

will inevitably frequently result in misinterpretation

when investigations of process are based on it, or we

can aim at thè best substantiated phylogeny possible

on all thè evidence and then, if necessary, customise

this for specifìc investigations.

It has sometimes also been said that thè attempt

to expose thè hierarchical pattern of taxa and their

characters is an important test of evolution, which

would be lost if evolutionary process was not

rigorously excluded from thè procedure. Presum-

ably, this is because a hierarchical structure is

thought to be expected if both anagenesis and cla¬

dogenesi occur, but lack of hierarchy would not

disprove evolution for it might be caused by ex-

cessive parallelism, convergence and reversal. Fur¬

thermore, thè taxonomocentric view that hierarchy

is especially important as support for evolution is

wrong; most evidence Comes from a combination of

other sources such as thè fossil record, thè nature of

thè genetic mechanism and direct observation of

short-term change in populations and intraspecifìc

lineages. In fact there is no reason why simple cladis¬

tic hierarchies should not be generated separately

from attempts to reconstruct phylogeny, if they are

needed.

An alternative view of thè relationship between

hierarchy and evolution is that thè former demands

an explanation, giving a reason for invoking evolu¬

tion to provide it (Panchen, 1992). Leaving aside thè

fact that a well marked hierarchy is often not discern-

ible, it can be argued that thè reverse is thè case: evo¬

lution gives a reason why hierarchy is not unexpect-

ed and should be searched for rather than some

other kind of order.

SS IN PHYLOGENY RECONSTRUCTION

Thus, embryology suggests that thè digits in thè wing

of birds are numbers 2, 3 and 4 and not necessarily

numbers 1, 2 and 3, as their phalangeal formula in

Archaeopteryx seems to indicate (Hinchcliffe, 1992).

Developmental information, can allow character Sta¬

tes to be defìned more clearly. For instance, thè limb

pattern that delineates tetrapods may be better speci-

fìed by thè way it develops than by its highly varied

final morphology (Hinchcliffe, 1992).

Assessing character independence

For characters to make an individuai contribution

to thè establishment of relationships, they have to be

evolutionarily independent of others that are used.

Whenever derived States of different characters cor¬

relate in their distribution across taxonomic units

there is thè possibility that they are not autonomous

and process information may be helpful in detecting

whether this is so. For instance, evidence of shared

genetic control can be searched for (Shaffer, 1986)

and ontogenetic considerations of epigenetic interac-

tions may also be helpful. In some salamander

groups, thè fìfth hind digit is usually suppressed but

develops when a large body-size is attained (Wake,

12

E. N. ARNOLD

1991). Therefore these two features cannot be used

as independent indicatore of relationship. Ecological

and functional cues may also be employed in this

way. The various features developed by dune dwel-

ling lizards that enable them to exclude sand from

their body orifices are likely to be heavily selected for

by this environment and consequently likely to evol¬

ve as a syndrome.

Sequence of change in transformation series

and between different characters

Ontogenetic sequence is sometimes used for pola-

rising character state transformations and many pat¬

tern cladists regard this ‘direct’ method of polarity

assessment as more appropriate than outgroup com-

parison (Nelson, 1978). However, like outgroup com-

parison it is not a procedure that can be universally

applied, since molecules and some organisms lack an

ontogeny. Furthermore thè claim that ontogeny is a

direct method is true only of its observability and not

of its relationship to phylogeny and its reflection of

this. Total reliance on ontogenetic polarity determi-

nation would also mean that developmental sequen-

ces could not easily be used as different character

States.

Ontogenetic polarity is assigned, either on thè

basis that primitive States are more generally distri-

buted among adult and earlier stages of thè taxa con-

cerned (Nelson, 1978) or on thè supposition that they

appear earlier in ontogeny (Hennig, 1966). In terms

of phylogeny reconstruction, thè former is a special

case of ingroup analysis (common = primitive) and

suffers from thè problems characteristic of this ap-

proach (Kluge, 1985). There is no reason to assume

a priori that ontogenetic sequence will generally

reflect phylogenetic sequence faithfully. This is so-

mething that can only be tested by comparing onto¬

genetic data for particular characters with thè more

direct phylogenetic inferences provided by outgroup

analysis. Characters chosen for such comparison

should have thè assumed primitive state present in

more than one immediate outgroup and direct and

parsimonious transfer to other States in thè studied

group. Such comparisons suggest that de-differentia-

tion, paedomorphosis and deletion of developmental

stages sometimes result in misleading ontogenetic

indications of phylogenetic polarity. Nevertheless,

there is an often marked if incomplete congruence

between ontogenetic and outgroup inferences. This

being so, ontogenetic criteria might be used when

outgroup information is not available, or is weak or

equivocai. Confidence about polarity is increased

when outgroup and ontogenetic information give si-

milar results. However, when these indicatore are

both available but point in different directions there

is no reason to give priority to thè less direct indica-

tion of phylogenetic polarity provided by ontogeny.

Indications of thè order of state and character

change can also be gained from knowledge of how

characters interact functionally (Arnold, 1981). To

use such information in assessing polarity, it is usual-

ly necessary to make an assumption about how evo-

lution proceeds. For instance, that new traits generally

develop or at least become widely spread through

populations in situations where a performance ad-

vantage is conferred. As will be argued, such as-

sumptions are susceptible to independent test.

Labial scales in phrynosomatid sand lizards

The phrynosomatid lizards of North America

show three basic patterns of upper labial scales: rec-

tangular and fiat; obliquely elongated with a diag-

onal keel; and obliquely elongated with a horizontal

keel (Fig. la, c, d). Outgroup analysis suggests clearly

that oblique elongation and keeling as such are deri-

ved, but it gives no indication as to whether keeling

arose before or after elongation, or which orientation

of keeling is secondary. Diagonal keels form part of a

harmonious mechanism with obliquely elongated

upper labial scales. Lizards possessing them, such as

Callisaurus (Fig. le) evade pursuers by diving into

often relatively firm sand. The head is oscillated ra-

pidly about its longitudinal axis and thè diagonal

keels shave sand off thè sides of thè enlarging cavity

into which thè lizard moves. Oblique elongation of

thè upper labial scales increases thè length of thè in¬

dividuai keels and allows them to overlap horizontal-

ly, so thè total length of cutting edge applied to thè

substrate is increased (Arnold, 1995). Making thè as¬

sumption that traits generally arise in situations

where they confer performance advantage, it seems

likely that oblique elongation of thè labial scales

arose after diagonal keeling, since thè former would

not confer advantage in elongating thè keels until

these arose.

Fig. 1 - Diagrammatic representations of thè upper labial scales

of North American sand lizards (Phrynosomatidae); thick lines

indicate keels. a. primitive condition (for instance Sceloporus) -

rectangular and unkeeled; b. hypothetical condition - rectangular

with diagonal Keels; c. derived condition (for instance Calli¬

saurus) - obliquely elongated with diagonal keels; d. derived

condition (nothern species of Urna) - obliquely elongated with

horizontal keels. Functional considerations suggest that thè evo-

lutionary sequence was from a. through b. and c. to d, providing

evidence that oblique scale elongation arose after diagonal keel¬

ing and horzontal keeling after this.

THE ROLE OF BIOLOGICA!. PROCESS IN PHYLOGENETICS

13

Horizontal keels on obliquely elongated scales

(Fig. ld) occur in species of Urna that burrow in very

loose sand, partly by moving thè head from side to

side. The keels confer performance advantage by

forming a lateral ridge that facilitates such sideways

movement. In this situation, thè oblique elongation

of thè labial scales has no discernible function,

something corroborated by its absence in numerous

independently evolved loose-sand burrowers. Func-

tional considerations consequently strongly indicate

that diagonal keels arose in thè context of burrowing

into firm sand, oblique elongation of thè scales follo-

wed and fìnally thè keels were reorientated to a hori¬

zontal position for use in soft sand.

It could be argued that events may have been

more complex, for instance that oblique elongation

of thè scales arose in some other context and was

only later co-opted to sand drilling. This of course is a

possibility but, unless there is evidence for such greater

complexity, thè principle of parsimony should be

applied, as for any other source of phylogenetic in-

ference.

Gecko toes

Another example of thè use of function is provid-

ed by thè digits of gekkotan lizards. In different taxa,

toes can be simple in structure without adhesive

pads or internai muscles, or with both these features,

or with one of them but not thè other. There is con¬

sequently a classic incompatibility between two two-

state characters (Le Quesne, 1969) (Fig. 2). It is ap-

parent from outgroup comparison that absence of

pads and muscles are thè primitive States, so at least

one character must be homoplasious, either having

reversed or developed its derived state in parallel.

However, it is not apparent which character this was,

which of thè two possible events were involved, and

whether pads developed before muscles or vice

versa.

Fig. 2 - Conditions found in thè toes of geckoes (Gekkota): A -

no pads, A’ - pads present; B - no muscles, B’ - muscles present.

These two binary characters exist in all four possible state combi-

nations constituting a Le Quesne incompatability indicating that

homoplasy must be present. Outgroup comparison establishes

that A and B are thè primitive States and thin arrows indicate

possible directions of change. Functional considerations suggest

that changes were as indicated by thick arrows.

Gecko toe pads confer performance advantages in

many climbing situations by allowing adhesion to

smooth and precipitous surfaces and there are many

cases where they function without muscles. Howe¬

ver, when muscles are present with pads, thè former

enable thè adhesive mechanism to be used more pre-

cisely and thè toes to be more easily detached, so

that effìciency is increased (Russell, 1977). Species

with muscles but no pads are usually ground-dwel-

ling like many primitive taxa with neither of these

structures and any benefits conferred by thè muscles

in this situation seem slight. If again traits are assu-

med to usually originate in situations where they

confer a distinct performance advantage, it seems li-

kely that muscles developed only after thè origin of

pads. Consequently, digits with muscles alone will

have arisen by secondary loss of pads, rather than by

independent origin of muscles.

As with ontogenetic cues, functional indications

of order of state and character change can be used on

their own when other lines of evidence are not avail-

able, or to increase or decrease confìdence in deci-

sions made on other grounds. This can be done be¬

fore or after initial phylogeny estimation. In thè ex-

amples just given, thè functional assessments of

order of change corroborate those found on phylo-

genies based on a wide range of other characters.

Functional considerations in ontogeny may also

provide insight about order of character origin in

phylogeny. For instance, if thè presence of one trait

is necessary for thè development of another, it seems

more likely that thè former arose fìrst. Of course this

may not be so, for instance if thè second trait was

only secondarily developmentally dependent on thè

fìrst, but provisionai acceptance is appropriate.

Weighting

Since apparently derived States of different charac¬

ters in a data set often suggest different relationships

for taxa, some characters must be better indicators of

relationship than others, unless all characters mis-

lead. In this situation, it would be helpful to be able

to distinguish States likely to reflect genealogical re¬

lationships from those where this is less probable. In

attempting this we are frequently trying to determine

thè likely lability of derived States. An ideal marker

of a clade is a derived state in which all possible

changes involving it are unlikely (Fig. 3). This would

mean that unique origin without independent deve-

lopments was probable and that thè state would per-

sist without changing by reversai back to thè originai

condition. Nor would it be likely to convert to an al¬

ternative derived state which other taxa have develo¬

ped, or become unrecognisable by disappearance or

further modification.

Weighting involves relative assessment of thè

probabilities of some or all of these transitions in

different characters. Although low lability is likely

to be frequent in informative States, it is also poss¬

ible to envisage less stable traits that nonetheless

give good information about phylogeny because

their successive States specify a series of increa-

singly less inclusive clades. However, such features

can often be treated as a nested series of stable cha¬

racters.

14

E. N. ARNOLD

Unrecognisable

derived state

1 '

Fig. 3 - Some possible changes involving a derived character

state (1). Its possible value in delineating a clade by all thè mem-

bers possessing it depends on thè possession of low transition

probabilities to other States. A perfect phylogenetic indicator

would have a low probability of arising from thè primitive state

(0) thus restricting parallel development, and low probabilities of

reversing to thè primitive state, of changing to another derived

state (2) causing convergence, or to an unrecognisable derived

state (F) resulting in apparent absence. Most weighting indica-

tors involve assessing some or all of these transition possibilities

in a relative way.

1. Compatibility approaches. Le Quesne tests (Le

Quesne, 1969) can be used to detect thè presence of

homoplasy in pairs of two-state characters and vari-

ous procedures can be employed to recognise a cli-

que of congruent characters and assign some kind of

relative weight to thè rest based on their perceived

conflict (Gauld & Underwood, 1986; Sharkey, 1989).

Such information can be used directly to form a hy-

pothesis of relationship or employed as a character

weighting System to choose among alternative trees

produced by parsimony approaches. The use of com¬

patibility methods in phylogeny reconstruction in-

volves no hypotheses of process, apart from that evo-

lutionary change occurs and that some characters are

more labile than others. However, it should be borne

in mind that, as in parsimony analysis, not all homo¬

plasy will necessarily be detected so, on occasion,

characters with fewer incompatibilities may be more

homoplastic. Similarly, congruent cliques of charac¬

ters are not necessarily thè result of branching desc-

ent and may sometimes be due to convergence.

2. Homoplasy in thè studied group. The idea that

characters weight themselves by their congruence

(Darwin, 1859; Patterson, 1982) can be applied after

initial analysis. Characters that show more step chan¬

ges at this stage can be regarded as being likely to be

more labile than others and consequently downgrad-

ed before thè analysis is re-run. The process can be

repeated until a stable pattern is produced (Farris,

1969). An alternative approach is discussed by Golo-

boff (1993). Although evolutionary assumptions are

denied for this successive approximations approach

(Goloboff, 1993) there is a clear process expectation

about thè way characters behave: ones that exhibit

apparent homoplasy are more likely to have produ¬

ced homoplasies elsewhere than others.

3. Homoplasy in outgroups. Knowledge of out-

groups may make it apparent that a particular feature

has evolved, or been lost or modified in thè same

way, a number of times. This is suggestive evidence

that thè change concerned may be easily produced

and consequently more than one appearance in thè

studied group is not unlikely. Such indications of

multiple occurrence involve a process assumption,

that similar organisms are likely to have similar pro-

pensities for particular character changes. The more

cases of independent occurrence that can be recogni-

sed, thè more closely related to thè studied group

and thè more similar to it outgroups are, thè stronger

thè case that such changes are likely to have occurred

more than once in thè studied group.

Conversely, certain features and systems, such as

some genital characteristics, frequently give good in¬

formation about relationships, judged by their frequ-

ent congruence with other characters. If this is so in

immediate outgroups it is more likely to be so in thè

studied group.

4. Evidence of relative trait lability derived from

thè studied organisms

a. Variability of state expression in a wide range of

taxa and lack of a clear gap between States can both

be regarded as indications of potential lability. Expe-

rience with animai and plant breeding provides evi¬

dence that features which are variable or sub-conti-

nuous are often prone to change. Ideally, direct ex-

periment on members of thè studied group itself and

its immediate outgroup could provide evidence of

this lability, its likely universal occurrence in thè his-

tory of thè group and any bias in direction of change.

b. Evidence from developmental mechanics. Exa-

mination of thè developmental process and experi-

ment may provide evidence that some ontogenetic

changes are more or less likely to occur than others;

something that applies to shifts between derived States

as well as their origins. If a series of traits are each deve-

lopmentally dependent on thè one preceding them in

thè sequence, thè last are more likely to be lost than thè

first since so many others are dependent on these (part

of thè concept of burden - Riedl, 1979). As with varia¬

bility, examination of taxa within thè studied group

and its immediate outgroup can provide evidence

that such developmental characteristics are generai.

5. Evidence of trait lability derived from possible

selective interactions between thè organism and thè

environment.

a. When there are multiple occurrences of a state

in outgroups or thè studied group or both, and these

correlate with some aspect of thè environment, it is

likely that this aspect or some related factor exerts

selective pressure for thè development of that state,

or at least favours its persistence, so that it is more li¬

kely to occur in that situation. For instance, thè nu-

merous independent developments of lateral fringes

of pointed scales on thè toes of lizards are nearly al-

ways associated with locomotion over fluid or semi¬

fluid media, especially aeolian sand (Luke, 1986).

b. The case for selective pressure for thè develop¬

ment of particular States in a particular environments in

enhanced if thè way thè change confers performance

advantage can be discemed. In thè above case, there is

experimental evidence that thè toe fringes prevent or

limit sinking into thè fluid medium concerned and

thus improve locomotory capacity (Carothers, 1986).

c. Conversely functional interaction with thè envi¬

ronment may provide evidence as to why certain

transitions between States involving thè same cha¬

racters are unlikely to occur. Many flattened crevice-

dwelling lizards have eyes that project above thè

skull but when they enter a fìssure these are depres-

sed and their lower section projects into thè buccal

cavity from which it is separated by a flexible mem¬

brane. However thè way this occurs varies: in scin-

cids and lacertids thè eye projects through thè subor¬

bitai foramen, while in cordylids it moves partly into

THE ROLE OF BIOLOGICA!. PROCESS IN PHYLOGENETICS

15

thè interpterygoid vacuity. As these two openings are

separateci by bone, neither solution can be converted

into thè other without a loss of function. This would

involve a reversion to thè primitive condition where

eye is unable to bulge into thè buccal cavity.

d. Sometimes Dossible functional organ systems

may have inherent characteristics that seem likely to

afTect their probability of change. Thus a case can be

made that some genital features are likely to persist

because they have to conform to those of thè opposi-

te sex and are also substantially buffered from envi-

ronmental influences (Arnold, 1973, 1986).

Other weighting criteria have been suggested, for

instance that complex characters are more likely to

indicate relationships as they are less likely to evolve.

However, direct knowledge of developmental me-

chanics of thè feature concemed is likely to be a better

indicator as to whether features are likely to develop

in thè same way and also of their likely persistence.

How should weighting factors and other inferences

from process be used?

Not unexpectedly, thè different weighting factors

discussed often show correlation with at least some

of thè others. Such agreement of several factors is a

much more convincing indication of potential evolu-

tionary lability than any one indicator and should be

looked for.

On occasion, there is a marked conflict in weight¬

ing factors, with compatibility and successive appro-

ximations methods largely supporting thè initial

results of parsimony analysis, while thè other indi-

cators largely based on biological process suggest an

alternative phylogeny. In such a case thè latter indi¬

catore should stili be considered seriously since they

are completely independent, differing entirely in

their rationale from parismony, compatibility and

successive approximations which all depend on in-

group character distribution.

Compatibility indicatore can easily be assigned a

numerical value (Farris 1969; Wilkinson, 1993)

which could be used to weight character States either

before or after parsimony analysis. Most other fac¬

tors are relative and qualitative and it seems best to

. use them only when preliminary parsimony analysis

has been completed (Arnold, 1981; Wheeler, 1986).

They may then be employed to choose between al¬

ternative trees, particularly between those involving

different sets of congruent characters. Another rea-

son for applying weighting factors after initial analy¬

sis is that, while they may indicate which traits are

more likely to give misleading information about re¬

lationships, they do not show that this is actually thè

case. Pontentially weak characters may sometimes

indicate reai relationships and should be given thè

opportunity to do so.

Even when parsimony analysis produces an une-

quivocal version of some or all thè relationships con-

stituting a phylogeny, weighting factors stili have a

potential role. They may be used to judge thè degree

of support for particular relationships by assessing

thè potential lability and independence of thè cha¬

racters delineating thè clades concerned. This is not

a substitute for statistical approaches, such as boots-

trapping (Felsenstein, 1985) and permutation tests

(Archie, 1989a, 1989b; Faith & Cranston 1991) but an

independent source of inference.

An example of weighting in selected primitive

lacertid lizards

Some characters varying among selected primitive

lacertid lizards are listed in Table 1 and their distri-

butions shown in Table 2. Parsimony analysis of thè

whole data set, using thè Henning 86 program for

phylogenetic inference (Farris, 1988) results in 31

trees of 59 steps and a consistency index of 0.50. A

consensus tree produced by thè Nelsen subprogram

is shown in Fig. 4. This associates a group of species

(A, C, E, G, I and K) in which all, or nearly all, of an

assemblage of 14 characters (numbers 17-30) are

present. Examination of thè data set as a whole

shows considerable conflict. When thè group of

strongly congruent characters 17-30 are removed,

analysis of thè remaining 1-16 shows that they too

have strong internai congruence, a single tree of21

steps and a consistency index of 0.76 being produ¬

ced. As might be expected, this specifìes a complete¬

ly different pattern of relationships with thè species

previously associated by characters 17-30 being wide-

ly distributed though thè tree (Fig. 5).

Table 1. Some characters varying among selected

primitive lacertids; see Arnold (1973, 1989) for fur-

ther details.

1. No pineal fontanelle.

2. Mediai loop of clavicle continuous.

3. Mediai expansion of clavicle restri cted.

4. Arms of interclavicle directed obliquely poste-

riorly.

5. Sternum with a heart-shaped fontanelle.

6. Two pairs of diverging transverse processes on

proximal autotomic caudal vertebrae.

7. Parietal scale extends to edge of parietal table of

skull posteriorly.

8. Parietal table extends to edge of parietal table of

skull anteriorly.

9. Supratemporal scale narrow.

10. Hemipenis with an armature.

11. Lobes flattened and complexly folded in une-

verted hemipenis.

12. Hemipenial lobes long.

13. Hemipenial lips large.

14. Genital sinus unlobed.

15. Oviducts enter genital sinus at tip(s).

16. Ulnar nerve follows ’varanide’ route.

17. Head and body depressed.

18. External nares of skull large.

19. Supraocular osteoderms fenestrated in adults.

20. Frontoparietal suture relatively simple.

21. Subocular foramen relatively large and rounded.

22. Dorsal scales fiat and unkeeled and not markedly

imbricate.

23. Collar beneath throat smooth-edged.

24. Ventral body scales more or less rectangular.

25. Ventral body scales not markedly imbricate.

26. Toes laterally compressed.

27. Toes markedly kinked.

28. Tail relatively fragile, usually with a high inci-

dence of breakage and regeneration.

29. Dorsal colouring often uniform or with redol¬

iate pattern.

30. Tail often blue, at least in juveniles.

16

E. N. ARNOLD

Table 2 - Distribution of some characters varying among selected primitive lacertid lizards.

Character

6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

Ancestral state

A. Lacerta oxycephala

B. Lacerta laevi s

C. Podarci s h, h i spani ca

D. Podarci s tauri ca

E. Lacerta perspici l lata

F. Lacerta andreanszki i

G. Lacerta cyanura.

H. Lacerta jayakari

I . Holaspi s guenther i

J . Adol fus alleni

K. Lacerta cappadocica

0000000000

0000001000

0000101000

0 0 0 0 1 1 1 1 1 0

0 0 0 1 0 0 1 1 0 0

0000001 100

0000000001

11110 0 110 1

1 1 1 0 0 0 1 1 0 1

0000000000

0 0 0 0 0 0 1 1 1 1

0010000000

0 110 10 1111

0 1 1 0 1 0 0 0 0 0

0 0 1 0 0 0 1 1 1 1

0000000000

1 - - 0 0 1 1 1 1 1

1 - - 0 0 1 0 0 0 0

1 - - 1 1 1 1 1 1 1

1 - - 1 1 1 0 0 0 0

1 0 0 0 0 0 1 1 1 1

0000000000

1111111111

0000100000

1111110 111

0000000000

1111111111

0 0 1 1 1 1 0 0 0 0

1111111111

0 10 11110 10

1111111111

0000000000

1110 111111

• •

Fig. 4 - Relationships of primitive lacertid lizards based on 30

characters. Parsimony analysis associates species A,C,E,G,I and

K (dotted) which share all or most of characters 17-30 (Table 1).

fig. 5 - Relationships of primitive lacertid lizards based on 16

characters, excluding numbers 17-30 (Table 1). The apparent re¬

lationships of thè six species associated in Fig. 4 (dotted). are

now radically different. For further explanation, see text.

Cladistic methodology demands that thè version

of phylogeny involving all available characters and

least steps should be accepted, but this would give no

consideration to substantial conflicting structure that

could represent genealogy and excludes relevant in-

formation about likely character labiiity. When poss-

ible weighting factors are considered, characters 17-

30 that associate species A, C, E, G, I and K show far

more of thè indications of labiiity listed earlier. They

are frequently intraspecifically variable, sometimes

with thè derived state not being abruptly separated

from thè primitive one, and many have evolved fre¬

quently in outgroups. Some osteological character

States involve simple retardation of ossifìcation.

These characters occur, both in thè studied group

and in several outgroups, in a particular environmen-

tal situation in which they confer performance ad-

vantage, namely steep open surfaces with narrow

crevices, whether rock faces or tree boles. Characters

17-25 are beneficiai in using fissures, especially as re-

fuges, 26 and 27 during locomotion on steep surfa¬

ces, and 28-30 in limiting predation (Arnold, 1973).

In contrast, thè remaining characters lack all or most

of these indications of labiiity.

In this situation where conflicting sets of charac¬

ters differ so clearly in weighting factors, there is a

case for downgrading thè set with strong indications

of evolutionary labiiity and accepting thè version of

events suggested by thè other. It might be predicted

that if more characters are looked at, any that show

strong congruence with characters 17-30 are likely to

confer advantage in rocky situations.

Testing thè assumptions involved in weighting

and other uses of biological process

Some weighting factors involve relatively little in

thè way of premises, for instance compatibility ap-

proaches. Others merely assume that similar orga¬

nismi and their attributes are likely to have similar

evolutionary propensities. In thè case of multiple oc-

currence in outgroups, this assumption is substan-

tially self-testing, if a number of examples of inde-

pendent origin exist. As noted, checking ingroup

members and immediate outgroups can establish

that a tendency to variability or a developmental cha-

racteristic is likely to have been present throughout

thè history of thè studied group.

THE ROLE OF BIOLOGICA!. PROCESS IN PHYLOGENETICS

17

The main area requiring test involves evolution-

ary assumptions, such as that traits tend to develop

in situations where they confer a performance

advantage. Evidence for such a regularity includes

thè fact that a mechanism capable of producing it,

naturai selection, exists. Furthermore, this and an

appropriate genetic System have been demonstrated

in such a wide range of organisms that they may

most parsimoniously be assumed to have been uni¬

versali present during thè evolution of contempor-

ary forms.

A more direct way of investigating thè generality of

thè assumption involves considering groups where

simple parsimony analysis produces well substantiat-

ed hierarchies of taxa without much character confl-

ict. As noted, these hierarchies can be regarded as ro-

bust hypotheses of phylogeny although, if desired

other indications of robustness might be looked for,

so long as they do not involve thè assumption being

tested. Such phylogenies can be integrated with in-

formation about thè environments taxa inhabit and

thè performance advantages traits produce in thè sit¬

uations concerned. It is then sometimes possible to

reconstruct changing conditions on lineages and see

whether traits do actually develop at thè times when

they fìrst confer benefit.

The lacertid lizard genus, Meroles, has a strongly

supported phylogeny with its principal lineage ex-

tending steadily through a series of increasingly

sandy habitats. No less than 70% of 61 shared derived

binary characters appear on thè main lineage at thè

points where they produce obvious advantage (Ar¬

nold, 1990). Included are features associated with lo-

comotion on fìrm and then loose sandy surfaces,

with diving into aeolian sand and its exclusion from

thè body, with sub-sand respiration and with ca-

mouflage on uniform surfaces. Such studies need to

be carried out on as many robust cladistic phyloge¬

nies as possible to establish thè generality of thè as¬

sumption. As yet they have rarely been attempted

but search for such a generai correlation in time

would provide a much more rigorous test of thè im-

portance of adaptation in evolution, than merely

searching for contemporary correlations between

traits and environments in which they produce per-

t formance advantage.

DNA base sequence analysis and thè virtues

of multiple approaches

The history of using DNA sequence as a source of

phylogenetic information is illuminating. The deve-

lopment of this fìeld has been substantially inde-

pendent of thè use of larger morphological features,

yet it shows interesting similarities albeit on an ab-

breviated time scale. There was an initial optimistic

feeling that most sequence was utilisable and its con-

version into phylogenetic information would be

straightforward. However, problems of analysis are

considerable, congruence between different molecu-

lar phylogenies is often elusive (Patterson, Humph-

ries & William, 1993) and some areas of sequence ap¬

pear much more informative than others. There have

consequently been efforts to recognise parts of thè

genotype that are more likely to be reliable, character

weighting in effect. Thus, changes in functional parts

of thè sequence may be assigned greater significance

because they are less likely to alter. For instance fìrst

and second base sites that specify amino acids mak-

ing up proteins are often favoured compared with

third-base sites. Relative probability of different

kinds of changes between bases is also frequently

taken into consideration. Transversions are often

rarer than transitions and there are Chemical reasons

why this should be so; consequently they are often

given higher weight. As in gross morphology, parti-

cularly complex molecular characters have been re¬

garded as more reliable taxonomic markers because

convergent origin is thought to be highly unlikely;

for instance thè BC1 RNA, a tRNA retroposon that

may specify thè Rodentia (Martignetti & Brosius,

1993).

Eclectic morphological systematists have someti¬

mes felt a little smug about thè increasingly percei-

ved problems of interpreting DNA sequence. Some

of them experience an unworthy twinge of Schaden-

freude when watching people pay large laboratory

costs to get into thè same kind of procedural diffìcul-

ties, that they themselves often managed for thè

price of a few scalpel blades, especially as attempts to

amellorate thè problems encountered often involve

thè same generai approaches. But there are positive

lessons that many morphologists can learn from

DNA studies. In particular a willingness not to be

tied to a single method of phylogenetic inference

(see for instance Kim, 1993). As often portrayed, thè

pattern-process approach tends to be proscriptive,

being presented as thè only way of proceeding. This

not only limits attempts to explore weighting me-

thods that could be used in conjunction with it, but

also precludes thè employment of multiple approa¬

ches. If one method can be certainly recognised as

superior in all circumstances then others can be dis-

carded, but in phylogeny reconstruction this is by no

means clearly thè case. Available methods vary in

thè way they act and in thè situations and ways in

which they may fail. Cladistic parsimony approaches

work well so long as change is relatively rare (Fel-

senstein, 1978), they tend to assign homoplasy to a

wide range of characters and while they have thè ad¬

vantage of inevitably producing trees which usually

have substantial structure, many alternatives may

exist. In contrast, compatibility methods, although

related to parsimony approaches (Felsenstein, 1988)

tend to concentrate homoplasy in a smaller range of

characters and, although they can be used to produce

a single hypothesis of relationships, this often lacks

complete resolution. In such a situation, where me¬

thods have different properties and are likely to re-

flect phylogeny better in different circumstances,

there is a case for using all of them, unless there is

evidence that they are clandestine versions of each

other. Points of agreement will thus be more robust-

ly supported (thè principle of consilience - Whewell,

1840). Multiple methods have often been used in thè

history of Science. For instance, acceptance of thè

reality of molecules and atoms depended crucially

upon thè remarkable agreement provided by more

than thirteen independent methods that were used

to determine Avogadro’s number (M. Wilkinson,

personal communication).

Another approach that is being put to increasing

use in DNA sequence analysis is likelihood methods

(Felsenstein, 1981). These require some estimate to

be made of transition possibilities between thè States

18

E. N. ARNOLD

of characters, so weighting factors may eventually

allow these methods to be broadly applied to mor-

phological data, at least in limited form, and perhaps

used in multiple method approaches.

Problems of using phylogenetics to study process

As already mentioned, one way of avoiding pro¬

blems of circularity when testing assumptions of

evolutionary process is to use robust unequivocal

cladistic phylogenies that do not incorporate such as¬

sumptions. Alternatively, any process assumptions

likely to produce circularity can be purged before-

hand by eliminating them and reworking thè remain-

ing data used to produce thè phylogeny concerned.

However, many studies of evolutionary process do

not involve reai problems of circularity. For instance,

because characters associated with rocky habitats

were downgraded in estimating a phylogeny of se-

lected primitive lacertids, it might be thought this

would interfere with any attempt to look for a statis-

tical correlation between such characters and those

habitats in lacertids (thè ‘comparative method’ of

Harvey & Pagel, 1991). In fact, thè rock characters

were downgraded on a variety of grounds only one of

which involved association with rocky habitats, so

thè latter could be discounted as to do so would not

affect thè results. Moreover, noting thè association

of character and habitat within lacertids did not in

itself involve any hypothesis of multiple occurrence

in thè studied group.

The observation of multiple association, as an in-

dication that thè features were easily produced in

rocky situations, applied only to outgroups. This

being so, there is no vicious circularity in a later use

of thè ‘comparative method’ within thè studied

group if desired.

Some problems of using phylogenies to study

process are essentially sociological. Until recently,

phylogenetic studies were of principal interest to sys-

tematists but, in recent years, ecologists, ethologists

and other biologists have become increasingly aware

of thè insights that phylogenies can bring to their

work. While thè development of such an audience is

encouraging, it involves pitfalls.

There is a tendency for outside users to underesti-

mate thè frequently very provisionai nature of phylo¬

genetic hypotheses. It is not always realised that thè

best available hypothesis is often not very robust and

very different almost as well substantiated alternati-

ves may exist. Users may also fail to consider as¬

sumptions involved in constructing phylogenies that

could lead to circularity in its utilizations. People

employing phylogenies need to have enough know-

ledge of systematic procedure to be aware of poten-

tial difficulties and make some assessment of them.

Perhaps thè relationship between thè manufac-

turer and user of phylogenies should be like that

between an ethical car-dealer and Client. While thè

former should make potential problems clear, thè

latter must be willing and able to make more obvious

checks on their own. As with vehicles, a reliable

manufacturer is a start, but checks on mode of pro¬

duction and generai robustness are very important.

Finally, potential users need to ask hether thè pro-

duct really fits their specifìc needs as it stands and, if

not, whether customisation may be a possibility.

Concluding remarks

The rigorous exclusion of most process from phy¬

logeny reconstruction by cladistic means may have

had thè virtue of concentrating attention on many

important issues, such as analysis of character trans-

formation, algorithms and computer programs used

in analysis, and thè relative virtues of parsimony and

other approaches. Now there is a consensus on some

of these basic problems, or at least clarifìcation of thè

arguments, there is a case for reconsidering thè role

of process.

Results of cladistic analysis suggest that it is often

insufficient on its own to produce robust hypotheses

of phylogeny. If such hypotheses are a primary requi-

rement, it is appropriate to incorporate any other

sources of inference that might improve this situa-

tion and can be justified, including many aspects of

biological process. Proper application of thè parsi¬

mony principle demands that such evidence should

not be excluded and any insistence on rigorously

avoiding differential weighting of characters cannot

be substantiated on any grounds but pragmatism.

That relevant process information is only sometimes

available and is occasionali shown to be misleading

is no reason for its rigorous elusion, especially as

these shortcomings also apply to other sources of

phylogenetic inference. Problems of circularity in

using phylogenetic hypotheses, in which process

considerations have been incorporated, are sur-

mountable. Certainly, phylogeny estimation should

not be automatically limited to parsimony analysis of

characters on thè grounds that this procedure has

virtues unrelated to thè task in hand, such as thè in¬

formation content of hierarchies produced or their

appropriateness as a basis for classification.

It has been argued that all direct character data

should be included in thè assessment of phylogenies,

if it can be sensibly integrated (Kluge, 1989; Eernisse

& Kluge, 1993), and this principal of total evidence

can be extended to encompass inferences on how

characters are likely to behave during evolution. This

also applies to using multiple indicators of order of

change and of character weighting, and multiple me¬

thods of analysis.

In thè approach suggested here, use of biological

process occurs mainly after straightforward parsimo¬

ny analysis so thè basic cladistic pattern can stili be

recovered and used for other purposes. It might be

pointed out that inferences from process are rarely

made in practice and there is no consensus about de-

tailed methods of procedure. This is presently so and

results largely from thè proscription of most process

considerations in cladistic methodologies, but thè

process approach deserves to be explored further. It

has thè incidental virtue that thè need for informa¬

tion on development and function and tests on as¬

sumptions about regularities in thè evolutionary

process will stimulate investigations in these areas. It

may seem excessively laborious to consider such

topics in phylogeny reconstruction, but these are

valid subjects of interest in themselves and relevant

to other areas of biology. The involvement of biolo¬

gical process in phylogenetics compares favourably

in this respect with thè drudgery of accumulating

DNA sequence, thè interest of which is largely limit¬

ed to reconstructing relationships. It also helps con¬

fimi thè centrai role of phylogenetics in integrating

THE ROLE OF BIOLOGICAL PROCESS IN PHYLOGENETICS

19

difTerent aspects of biology. Incorporating process

considerations inevitably complicates phylogeny re-

construction, but there is no reason to expect that

thè recovery of genealogical patterns will always be

simple.

In deciding how to perceive thè world, there is a

continuum of possibilities that may let us believe in

fairies at one extreme but not even believe our own

sense data at thè other. Modest movement in thè di¬

rection of increased scepticism is usually applauded

in intellectual pursuits, especially when it manifests

itself in overt procedural simplicity and rigorous re-

jection of what is perceived to be misleading evi-

dence. Insistence on limiting phylogeny reconstruc-

tion to straightforward cladistic techniques is part of

this trend but, in thè long run, simplicity must not be

bought at thè expense of excluding relevant sources

of inference. This is true even if such sources are

faulted themselves, provided faults are not too com¬

mon and independent of those in thè originai data

set. While incorporation of biological process invol-

ves a move away from simplicity, its incorporation

can be justifìed both in principle and practice. Think-

ing process is relevant in phylogenetics falls a long

way short of believing in fairies.

Acknowledgements. I am grateful to Giovanni Pinna,

Michael Ghiselin and Francesco Scudo for organis-

ing thè Workshop on Systematic Biology as an His-

torical Science, held in Milan in June, 1993. I also

thank thè participants in thè meeting for helpful

comment, expecially Michael Ghiselin and David

Wake. Mark Wilkinson carefully read a draft of this

paper and made a number of useful criticisms.

REFERENCES

Archie J. W., 1989a - A Randomization test for phylogenetic in-

formation in systematic data. Syst. Zool., 38:239-252.

Archie J. W., 1989b - Phylogenies of plant families: a demonstra-

tion of phylogenetic randomness in DNA sequence data de-

rived from proteins. Evolution, 43:1796-1800.

Arnold E. N., 1973 - Relationships of thè Palaearctic lizards as-

signed to thè genera Lacerta, Algyroides and Psammodromus

(Reptilia, Lacertidae). Bulletin of thè British Museum (Natu¬

rai History) (Zool.), 29: 289-366.

Arnold E. N., 1981 - Estimating phylogenies at low taxonomic

levels. Zeitschrift fùr Zoologische Systematik und Evolutions-

forschung, 9: 1-35.

Arnold E. N., 1986 - Why copulatory organs provide so many

useful taxonomic characters: thè origin and maintenance of

hemipenial differences in lacertid lizards (Reptilia: Lacerti¬

dae). Biological Journal of thè Linnean Society, 29: 263-281.

Arnold E. N., 1989 - Towards a phylogeny and biogeography of

thè Lacertidae: relationships within an Old-World family of

lizards derived from morphology. Bulletin of thè British Mu¬

seum (Naturai History) (Zool.), 55: 209-257.

Arnold E. N., 1990 - Why do morphological phylogenies vary in

quality? An investigation based on thè comparative history

of lizard clades. Proceedings of thè Royal Society of London,

B 240: 135-172.

Arnold E. N., 1994 - Investigating thè origins of performance

advantage: adaptation, exaptation and lineage effects. In

Phylogenetics and Ecology (eds P. Eggleton & R. I. Vane-

Wright). The Linnean Society of London. London: 123-168.

Arnold E. N., 1995 - Identifying thè effects of history on adapta¬

tion: origins of different sand-diving techniques in lizards.

Journal of Zoology, 235: 351-388.

Cesalpino A., 1583 - De plantis libri XIV. Florence.

Carothers J. H., 1986 - An experimental confirmation of mor¬

phological adaptation: toe fringes in thè sand-dwelling lizard

Urna scoparia. Evolution, 40: 871-874.

Darwin C., 1859 - On thè origin of species by means of naturai

Selection. J. Murray, London.

De Queiroz K., 1985 - The ontogenetic method for determining

character polarity and its relevance to phylogenetic syste-

matics. Systematic Zoology, 34: 280-299.

De Queiroz K. & Donoghue M. J., 1990 - Phylogenetic systemat-

ics or Nelsons’s version of cladistics. Cladistics, 6: 61-75.

Eernisse D. J. & Kluge A. G., 1993 - Taxonomic congruence ver¬

sus total evidence, and amniote phylogeny inferred from

fossils, molecules and morphology. Molecular Biology and

Evolution, 10: 1170-1195.

Eldridge N. & Cracraft J., 1980 - Phylogenetic Patterns and thè

Evolutionary Process: Method and Theory in Comparative Bio¬

logy. Colombia University Press, New York.

Faith D. P., 1991 - Cladistic permutation tests for monophyly

and nonmonophyly. Systematic Zoology, 40: 366-375.

Faith D. P. & Cranston P. S., 1991 - Could a cladogram this

short have arisen by chance?: on permutation tests for cla¬

distic structure. Cladistics, 7: 1-28.

Farris J. S., 1969 - A successive approximations approach to cha¬

racter weighting. Systematic Zoology, 18: 374-385.

Farris J. S., 1979 - The information content of thè phylogenetic

System. Systematic Zoology, 28: 483-519.

Farris J. S., 1980 - The efficient diagnoses of thè phylogenetic

System. Systematic Zoology, 29: 386-401.

Farris J. S., 1982 - Simplicity and informativeness in systematics

and phylogeny. Systematic Zoology, 31: 413-444.

Farris J. S., 1983 - The logicai basis of phylogenetic analysis. In:

Advances in Cladistics, voi. 2 (eds N.I. Platnick & V.A. Funk).

Columbia University Press, New York: 7- 36.

Farris J. S., 1985 - The pattern of cladistics. Cladistics, 1: 190-

201.

Farris J. S., 1988 - Henning86, program and documentation.

Port Jefferson, New York: published by thè author.

Felsenstein J., 1978 - Cases in which parsimony or compatibility

methods will be positively misleading. Systematic Zoology,

27: 401-410.

Felsenstein J., 1981 - Evolutionary trees from DNA sequences:

a maximum likelihood approach. Journal of Morphological

Evolution, 17: 368-376.

Felsenstein J., 1985 - Confidence limits on phylogenies: an ap¬

proach using thè bootstrap. Evolution, 39: 783-791.

Felsenstein J., 1988 - Phylogenies from molecular sequences:

inference and reliability. Annual Reviews of Genetics, 22: 521-

565.

Galbraith J. K., 1957 - The Affluent Society.

Gauld I. & Underwood G. L., 1986 - Some applications of thè Le

Quesne compatibility test. Biological Journal of thè Linnean

Society, 29: 191-222.

Gauthier J., Kluge A. G. & Rowe T., 1988 - Amniote phylogeny

and thè importance of fossils. Cladistics, 4: 105-209.

Goloboff P. A., 1993 - Estimating character weights during tree

search. Cladistics, 9: 83-91.

Harvey P. & Pagel M., 1991 - The Comparative Method. Oxford

University Press, Oxford.

Henning W., 1966 - Phylogenetic Systematics. University of Illi¬

nois Press, Urbana.

Hinchcliffe J. R., 1992 - Towards a homology of process: evo¬

lutionary implications of experimental studies on thè gene¬

ration of skeletal pattern in avian limb development. In

Organizational Constraints on thè Dynamics of Evolution (eds

J. Maynard Smith & G. Vida). Manchester University Press.

Manchester: 119-131.

Keynes J. M., 1921 - A treatise on Probability. Macmillan,

London.

Kim J., 1993 - Improving thè accuracy of phylogenetic estima-

tion by combining different methods. Systematic Biology, 42:

331-340.

Kluge A., 1985 - Ontogeny and phylogenetic systematics. Cla¬

distics, 1: 13-27.

Kluge A. G., 1989 - A concern for evidence and a phylogenetic

hypothesis of relationships among Epicrates (Boidae, Ser-

pentes). Systematic Zoology, 38: 7-25.

Le Quesne W. J., 1969 - A method of selection of characters in

numerical taxonomy. Systematic Zoology, 18: 201-205.

Luke C., 1986 - Convergent evolution of lizard toe fringes. Biolo¬

gical Journal of thè Linnean Society, 21: 1-16.

Manton S. M., 1977 - The Arthropoda: Habits, Functional Mor¬

phology and Evolution. Oxford University Press, Oxford.

Martinetti J. A. & Brosius J., 1993 - Proceedings of thè Na¬

tional Academy of Science. 90: 9698-9702.

20

E. N. ARNOLD

Mayr E., 1982 - The Growth of Biologica I Thought. Diversity, Evo-

lution and Inheritance. Harvard University Press, Cambridge,

Massachusetts.

Nelson G., 1978 - Ontogeny, phylogeny and biogenetic law. Sys-

tematic Zoology, 27: 324-345.

Nelson G. & Platnick N., 1981 - Systematics and Biogeography:

Cladistics and Vicariance. Colombia University Press, New York.

Panchen A. L., 1992 - Classification, evolution and thè nature of

biology. Cambridge University Press, Cambridge.

Patterson C., 1982 - Morphological characters and homology.

In Problems in Phylogenetic Reconstruction (K. A. Joysey &

A. E. Friday, eds). Systematics Association Special Volume.

Academic Press, London: 21: 21-74.

Patterson C., Humphries, C. J. & Williams D. M., 1993 - Con-

gruence between molecular and morphological phylogenies.

Annua l Review of Ecology and Systematics, 24: 153-188.

Piementel R. A. & Riggins R., 1987 - The nature of cladistic

data. Cladistics, 3: 201-209.

Platnick N.I., 1979 - Philosophy and thè transformation of cla¬

distics. Systematic Zoology, 28: 537-546.

Platnick N.I., 1985a - Philosophy and thè transformation of cla¬

distics revisited. Cladistics, 1: 87-94.

Platnick N.I., 1985b - On justifying cladistics. Clastics, 2: 83-85.

Riedl R., 1979 - Order in Living Organisms. J. Wiley, Chichester.

Russell A. P., 1977 - A contribution to thè functional analysis of

thè foot of thè Tokay, Gekko gecko (Reptilia: Gekkonidae).

Journal of Zoology, 176: 437-476.

Shaffer H. B., 1986 - Utility of quantitative genetic parameters

in character weighting. Systematic Zoology, 35: 124-134.

Sharkey M. J., 1989 - A hypothesis-independent method of cha¬

racter weighting for cladistic analysis. Cladisitics, 5: 63-86.

Trueman J. W. H., 1993 - Randomization confounded: a reply to

Carpenter. Cladistics, 9: 101-109.

Wake D., 1991 - Homoplasy: thè result of naturai selection or

evidence of design limitations? American Naturalist, 138:

543-567.

Wheeler Q. D., 1986 - Character weighting and cladistic analy¬

sis. Systematic Zoology, 35: 102-109.

Whewell W., 1840 - Philosophy of thè Inductive Sciences, founded

on their history. London.

Wilkinson M., 1992 - Ordered versus unordered characters. Cla¬

distics, 8: 375-385.

Wilkinson M., 1993 - Consensus, compatibility and missing

data. Unpublished PhD. Thesis, University of Bristol.

. Systematic Biology as an Historical Science

Memorie della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano

Volume XXVII - Fascicolo I - 1996

Yves Bouligand

Morphological singularìties and macroevolution

Abstract — Characters used in evolutionary studies lie at two extreme scales: millimeters or centimeters for instance in

conventional systematics and nanometers in sequences of aminoacids or nucleotides. However, intermediate organization

degrees do not escape naturai selection. Morphological singularìties belong to these intermediate levels and were defined by

Rosin and Picken; they correspond to locai rearrangements of tissue orientations and polarities, which belong to definite

topological classes, as shown in figures 28 to 39. The evolutionary interest of these singularìties comes from their likely role

in organization and from thè frequent differentiation of originai organs in their core. Examples of such small organs are

discussed in thè case of a narrow and homogeneous family of parasitic Copepods, and also in larger groups, as Annelids

with their characteristic bristles and Molluscs or other phyla, with closely related ultrastuctures.

The existence of morphological singularìties is probably at thè origin of diffìculties encountered in thè application of

d’Arcy Thompson’s method of continuous transformations. This theory preposes that limited changes in shape observed

in development and evolution can be described with thè help of a rectangular cartesian frame of coordinates, itself con-

tinuously transformed into a curvilinear grid; but it is clear that morphological accidents, as supplementary vertebrae or

fingers, make impossible such continuous mapping from one individuai to another one belonging to thè same species.

Singularìties must be introduced in coordinates grids themselves to apply d’Arcy Thompson’s methods.

More or less orthogonal arrays of fibrils exist in thè integument of many vertebrates or invertebrates and show defined

orientations in their anatomy. These fibrous lattices, which can be interpreted as a materialization of d’Arcy Thompson’s

coordinates frame, present singularìties with originai symmetries, someones being pentagonal. They were observed

by Rosin (1946) in thè basement membrane of amphibian tadpoles and more recently in thè cuticle of marine worms (Le-

pescheux, 1988). These singularìties create locai specific morphologies, which resemble locai simmetry breakings observed

in liquid crystals, and this is quite naturai, since self-assembly of fibrils is a morphogenetic process closely related to thè

phase transition involved in thè transformation of an ordinary liquid into a liquid crystal.

Small causes produce important effects in non stable conditions and for instance, simple genetic events may interfere

with hormonal regulations, leading to large morphological changes, as in heterochrony. Various kinds of instabilities occur

at thè level of morphological singularìties, but instead of changes considered along thè time axis, as in heterochrony, thè

relevant axes are those of coordinate grids. Such instabilities may intervene in thè distribution of singularìties over thè

whole body, or in thè structure of their associated small organs, when they exist. We cali heterotopies such processes and

consider their plausible macroevolutionary consequences.

Introduction

Works on evolution deal mainly with two kinds of

characters, considered at very different scales: 1. ma-

croscopic structures, generally observed in thè adult

morphology and 2. genes or molecules, rarely used

in current systematics. We pass from thè visible phe-

notype to thè less accessible genotype and we change

.thè scale from centimeters or millimeters to nano¬

meters. We learn which genes are involved in thè ex-

pression of some essential morphological characters,

but we stili ignore thè complex physico-chemical

steps necessary for thè elaboration of thè corres-

ponding characters in their whole structure. Many

counterexamples can be proposed and some come

from talks presented at this workshop, but much re-

mains to study within thè gap separating thè pheno-

type from thè genotype, despite thè recent successes

in developmental genetics.

Discussions are generally limited to these two ex¬

treme description levels and rather uncommon are

evolutionary discussions on fine structures at inter¬

mediate levels, within cells and tissues for instance.

Paleontologists rarely specialize in histology and

their studies are limited to bones and teeth in thè

case of vertebrates. Histology is present in compara¬

tive anatomy, but there are few evolutionary investi-

gations on tissues and cells studied for themselves

and say at thè ultrastructural level in generai.

It appears that there is a large range of organiza-

tional levels, between nanometers and millimeters,

which do not escape naturai selection and present a

high evolutionary interest, but are not generally con¬

sidered from this point of view in thè literature. Here

also, counterexamples exist, but not too many, and

thè reason for this is possibly thè generai diffìculty of

correlating changes within cells and tissues with

those observed in thè environment, which also are

described either in macroscopic terms or in molecu-

lar terms, thè intermediate structural levels again

being generally forgotten. However, such levels of

description offer new aspects in thè evolution of liv-

ing beings, which could be narrated and integrated to

this history, perhaps unique, of life at thè surface of

thè earth.

A series of examples taken from my own works are

now presented to show different diffìculties I exper-

ienced in studying precise examples of evolution.

Some mechanisms appeared to me as plausible, but

were not discussed in my published papers, since I

was unable to propose experiments or observations

affording thè beginning of a proof or of a refutation.

All thè considered examples will correspond in my

mind to macroevolution, since they involve either

changes which characterize higher groups, or chan¬

ges within smaller groups, but however sharply defi¬

ned. The concept of morphological singularity is due

to Rosin (1946) and comes from thè observation of

thè epidermal basement membrane in young tadpo¬

les, as will be illustrated below. These singularìties

are also presented in thè book of L. Picken (1960),

with a generai discussion on fibrous structures ob-

22

Y. BOULIGAND

served in thè integument of vertebrates and inverte-

brates. A morphological singularity can be defined as

a narrow locus lying at thè core of a rearrangement of

thè main orientations of certain tissues. Here, this

term will be used in several examples, in particular

for bristles in annelids and arthropods. The presence

of one of these small organs creates a locai rehandling

within thè structure of cuticle and epidermis, which can

be interpreted as a morphological singularity.

Macroevolution within an apparently

homogeneous family

Endoparasitic Copepods of Octocorals

Lamippids are parasitic copepods, a group of very

small crustacea (generally 1 mm long or less) living

in thè digestive cavities or possibly in thè mesogloea

of Octocorals (Anthozoa, Coelenterata), these ma¬

rine animals forming beautiful colonies of polyps

with octogonal symmetries, thè precious red coral

being thè classical example. When these endopara¬

sitic Crustacea are adult, their morphology is deeply

transformed and their wormlike body is then adapt-

ed to reptation within thè host tissues (figs. 1-4), thè

morphology being grossly that of certain endopara¬

sitic acarina, for instance, thè common mites of thè

human skin, Demodex folliculorum, or also that of

some mites in thè family of Eriophyidae, living in thè

leaves of woody plants. When I began to work on

these parasitic copepods with C. Deiamare- Debout-

teville, thè main review on this family was due to de

Zulueta, 1908-1910 (see references in Bouligand,

1966a) and represented an accurate systematic study,

with clear conclusions:

1. Most of thè Octocoral species present in waters

around Banyuls-sur-mer (Mediterranean Sea, near

thè frontier between Spain and France) are parasited,

and each species of parasite is found in only one

host. There are about fifteen known species of Octo¬

corals in this area, but only twelve are parasited by

Lamippids, and some of them by two different spe¬

cies of these parasites.

2. The morphology of each species is defined by

recognizable microscopie characters of thè four pairs

of appendages and of thè caudal furca.

3. The sexual dimorphism of Lamippids was said

to be limited to thè structure of genital apertures.

The sex ratio was highly variable among species, one

sex (either male or female) having never been obser-

ved for some species.

4. This family contained two genera, Lamippe and

Linaresia, thè second one with a unique species

known only by its male. Some different species of

Lamippe had been described from other seas, but ei¬

ther corresponded to species reviewed by de Zulueta

or to other species with characters indicating a dose

relationship with this genus. This family was con-

sidered to be very homogeneous.

My observations made thè situation much less

clear, but can be summarized as follows:

1. Some new species were observed and someones

suppressed with thè agreement of de Zulueta (1961).

An immature instar of reduced size, not much longer

than thè nauplius (fig. 5), was observed in several

species, with thè adult wormlike morphology, but

without genital apertures (fig. 6).

2. The rule of host specifìcity of parasites was ve-

rified in generai, but was less certain, since no

morphological differences were found between

individuals taken from some very different hosts.

The parallelism between thè two genealogies, that of

thè hosts and that of thè corresponding parasites,

suggested by thè host specifìcity of parasites is not

verifìed. There are many examples of closely related

species found in phyletically distant hosts.

3. There are endoparasitic Copepods in Tunicates

resembling strongly either thè genus Lamippe (and

that was already quoted by de Zulueta) or thè genus

Linaresia. These two genera possibly separated when

they were parasites of Octocorals, but this is not de-

monstrated, since thè host specifìcity is not so rigorous.

4. Examples of sexual dimorphism were also ob¬

served, some being slight, mainly a bigger volume of

females (fig. 8). On thè contrary, thè female and thè

young females of Linaresia were discovered and pre-

sented an extreme sexual dimorphism (figs. 9-12).

5. The morphologies of thè fifteen studied species

(from Banyuls mainly) were drawn in great detail.

The variations in thè distribution of bristles or setae,

within each species, are rare and were also described

(about 10 anomalies for 500 observed specimens: ad-

dition, absence, or modification of a bristle).

6. The cuticle of these parasites is made of an ho-

mogenous epicuticle (soft, flexible and elastic in thè

genus Lamippe ), observed on thè whole body, and a

rigid procuticle, limited to a set of sclerites present

mainly at thè level of thè head, of thè appendages, of

thè genital apertures and of thè furca. The epicuticle

alone forms thè arthrodial membrane, which is ex-

tremely developed at thè level of thè thorax and thè

abdomen. A wormlike anatomy is reconstructed in

thè genus Lamippe, with circular and longitudinal

muscles involved in peristaltic movements (Bouli¬

gand, 1966 a and b).

Visible macroevolution

The first half of this morphological study was pu-

blished, but I never completed thè manuscripts of

thè second half, simply because I tried to prepare a

classification dose to phylogeny, if possible, but I did

not succeed. Several tables were established for cha¬

racters varying as discrete entities between species

and, in principle, thè situation was good, but it was

necessary to look for other species, and this was

never done. I was only able with thè available infor-

mation to gather some species into subgroups and

not to build a complete genealogical tree.

It was clear (but I stili wait for a rigorous proof) that

thè strong sexual dimorphism, which was already vis¬

ible in thè young female of Linaresia, was secondary

relative to thè generai morphology of Lamippids,

present in males and in young females (except thè lat-

eral extensions already visible in these latter). It also

appears that an extreme macroevolution is possible

in this group, without affecting thè main characters

of thè other instars, recognizable for instance in thè

morphology of appendages, and which give thè best

elements for a defìnition of thè Lamippid family (fig.

13-16). The digestive System (mesenteron) is absent

(or deeply modified) in thè young female and in thè

adult female of Linaresia, whose cuticle is strongly

thickened and crossed by a complex System of bran-

ched and anastomosed canals (Bouligand, 1966 a, b).

MORPHOLOGICAL SINGULARITIES AND MACROEVOLUTION

23

Figs. 1-8 - 1) Schematic section of an Octocoral colony {Alcyonium palmatum) with two expanded polyps and a smaller

one in thè middle, being retracted. Several Lamippids are represented in thè canals of thè coenosarc, but are much less

numerous than represented: A: Lamippe aciculifera (adult or immature); F: Lamippe faurei; R: Lamippe rubicunda. 2) Simi-

lar section in thè Gorgonian: Paramuricea chamaeleon, with one expanded polyp and two retracted ones. M: Linaresia

mammifera (immature or mature females and males); P: Lamippe parva and S: Lamippe setigera. 3) Drawing of Lamippe

rubicunda observed alive, after extraction from its host ( Alcyonium palmatum or A. acaule). 4) The contracted body of

Lamippe rubicunda. 5) A lamippid nauplius observed in Alcyonium. 6, 7 and 8) Immature stage, male and female of Lamippe

aciculifera.

Figs. 9-12 - Linaresia mammilifera. 9) Ventral view of a young female. 10) Ventral view of a male. 11) Dorsal view of a

young female. 12) Ventral view of an adult female.

MORPHOLOGICAL SINGULARITIES AND MACROEVOLUTION

25

Figs. 13-16 - First thoracic legs of four different species of Lamippids. Hatched areas correspond to directly visible scleri-

tes, whereas dotted structures represent other sclerites observed by transparency. 13) Lamippe rubicunda; 14) Lamippe

/aurei; 15) Linaresia mammilifera ; 16) Lamippe aciculifera.

26

Y. BOULIGAND

Less visible macroevolutions

The integument of these copepods presents many

differentiations considered in figs 17-22. There are

for instance several types of papillae as shown in fig.

21. There are two other characters, already described

by de Zulueta, which separate two subgroups in thè

genus Lamippe.

The fìrst one corresponds to species showing at

thè tip of setae, a bunch of needles (or aciculae), with

refringent droplets slowly running along them, as for

axopods of certain planctonic protozoa (Actinopo-

da). In some Lamippids, thè aciculae are mainly ob-

served at thè furca (fìg. 19), whereas in other ones

they decorate all thè appendages (fìg. 20). In Lamippe

chattoni, they cover thè whole body, pointing outsi-

de, normally to thè arthrodial cuticle (fìgs. 17, 18).

I was convinced in thè fìrst years that this very unu-

sual character was thè signature of a synapomorphy,

but it was not confìrmed by thè other morphological

details of appendages, and I learnt that aciculae,

possibly related to those of Lamippids, existed in

other parasitic copepods of thè genus Pachypygus liv-

ing in tunicates (Hipeau- Jacquotte, 1986). These aci¬

culae of Pachypygus are made of a bundle of parallel

microtubules (as in Actinopods), an ultrastructure I

stili not verified in Lamippids, but in which I believe,

since there are visible droplets moving along these aci¬

culae, which were remarkably fìlmed by J. Painlevé.

The second character allowing one to separate a

second subgroup within thè genus Lamippe stili

holds and corresponds to another strange modifìca-

tion of setae, which are contractile, as shown in thè

figure 22. These slow deformations, also fìlmed by

J. Painlevé, are due to myofìbrils visible within these

transformed setae, in histological preparations. I

never heard of examples of this kind of structures in

any other Arthropods. I spent days in libraries to find

examples in literature of similar contractile setae

(and also setae with aciculae). I have spoken of this

problem with many colleagues. I suppose that thè

synapomorphy corresponding to thè presence of

contractile setae is genuine and I never changed my

opinion. The other morphological characters con¬

fimi this synapomorphy. However, there are only

three species in this subgroups and what had been

experienced with thè aciculae might reproduce with

these contractile setae.

My hypothesis was that a very originai character,

common to several species within a family, is gene-

rally attributed to thè signature of a common ances-

tor, but actually similar productions may appear in-

dependently in very different lineages. I suggest that

this is simply because thè expression of this charac¬

ter depends on thè overstepping of certain thre-

sholds and that this can be achieved by very different

genetic situations. There are no means to verify such

conjectures in thè present context of genetic and mo-

lecular studies and this is particularly obvious for

this sort of copepods. Current molecular research

with such animals is not easy, since one generally

fìnds them in small number and their dimensions

also are very small.

Relativity of macroevolution

The three different evolutionary characters dis-

cussed in this family of copepods (strong sexual di-

morphism, axopodlike aciculae and contractile

setae) correspond, in my mind, to three examples of

macroevolution. The fìrst one appears as obvious

from thè direct examination of thè external morpho-

logy, whereas, thè two other ones are purely micros¬

copie details, but very unusual.

Considered at thè histological level or at thè ul-

trastructural level, these variations, within this nar-

row family of parasitic copepods, can appear as im-

portant as those we know in thè whole phylum of

vertebrates, from fìshes to mammals. For instance,

do we know examples, in vertebrates of such involu-

tion of thè digestive canal, with a compensation

through thè skin, as in many parasitic worms? Sev¬

eral cases are known in other groups of crustaceans,

namely Sacculina, described in handbooks of zoolo-

gy. The diffìcult question remains to appreciate thè

genetic changes related to these extreme transforma-

tions. We can suppose for instance that genetic mo-

difìcations were small with respect to their consider-

able phenotypic consequences, since thè appendage

morphology is not deeply transformed in males and

in young females. On thè contrary, we can think that,

from thè separation between Lamippe and Linaresia,

which can be very ancient, thè genetic evolution has

been possibly considerable, with however few inci-

dence on thè appendage structure, since neutral me-

chanisms in evolution are also to be taken into ac-

count. Actually, there is no reai hope to verify all that

in thè next twenty years, if I am not mistaken.

D’Arcy Thompson’s theory and morphological

singularities

Diffìculties in thè application of thè theory

of transformations

Since I had prepared numerous drawings of thè

appendages of Lamippids, I have tried to apply thè

method of continuous deformation due to d’Arcy

Thompson, but I did not succeed. I stili think that

this method is based on an excellent idea, but there

are diffìculties. The book of d’Arcy Thompson

(1917), entitled On Growth and Form, deals with geo-

metrical and physical constraints faced by organisms

in thè course of development and evolution, but its

main impact comes from thè last chapter devoted to

this theory of transformations.

Briefly, this theory proposes that one passes from

thè form of a given species to that of a related one, by

a progressive deformation, which is that of a rectan-

gular cartesian frame of coordinates into a curvili-

near one, so that two small structures recognized as

homologous in thè two different species, have equal

coordinates in thè two arrays. I did not really obtain

such continuous mappings between most species of

Lamippids. The evident diffìculty comes from seg-

mentation and ramification of appendages. A simple

explanation can be considered in thè case of vertebra¬

tes: there are examples of supplementary vertebrae or

fìngers and such variations make thè continuous map-

ping from one individuai to another one impossible.

Like thè teeth of mammals, all bristles of Lamip¬

pids can be given a name, and species are differen-

tiated by thè presence or thè absence of some par-

ticular bristles (fìgs. 13-16). One can propose such

continuous deformations only at thè level of a series

MORPHOLOGICAL SINGULARITIES AND MACROEVOLUTION

27

Figs. 17-22 - Small organs in Lamippids. 17) Lamippe chattoni, with its cuticle covered by thin aciculae. 18) Enlarged view

of aciculae at thè surface of thè cuticle of Lamippe chattoni. 19) Groups of aciculae emerging at thè tip or some special ì zed

setae in Lamippe aciculifera. 20) In thè same species, isolated aciculae emerge from bristles of antennulae. 21) Papillae ob-

served on thè head of Linaresia and on thè body of different Lamippe. 22) Different shapes observed with furcal retracti e

setae in Lamippe rubicunda.

28

Y. BOULIGAND

of sclerifìed plates (or sclerites) well difTerentiated in

thè cuticle of thè thoracic appendages (figs. 23-26).

However, many problems remain unsolved even

in this situation. Well identified sclerites, such as j

and y in fìg. 23, disappear in some species (fig. 26).

Others are added (fìg. 24, a, 3). What can we do with

these sclerites which are either present or absent?

For instance, we do not know whether or not thè

sclerite y, present in figs. 23 and 25, is a piece of scle¬

rite present at level d (Fig. 24) or is different from it

(fìg. 26). Another problem is that of thè relative pro-

portion of arthrodial membrane, lying between thè

sclerites, which varies considerably between species.

Compare for instance fìgures 24 and 26, and particu-

larly thè zone B,efg mainly formed of arthrodial cut¬

icle in fìg. 24 and mainly sclerites in fìg. 26. Two op-

posite trends are observed in these two species. The

sclerites resemble pieces of a puzzle in fig. 26, with

little room for arthrodial membrane, whereas they

form elongated rods in fig. 24, with a maximum ex-

tension for thè arthrodial cuticle, and this trend is

visible in all thè parts of thè body.

Since continuous transformations are impossible,

singularities were introduced as shown in fig. 27, to

take into account such discrete variations, as thè in-

troduction of a new bristle, but thè problem is that

there are several ways to do that, with a more or less

arbitrary localization of singularities. It must be re-

called that singularities were considered in coordina-

tes grids, as possibly useful in thè interpretation of

experiments involving morphogens (Bookstein,

1981).

If some details are not taken into account, it is

possible to draw separately thè coordinate frames

and their deformations, at different levels of organi-

zation. Each bristle can receive its own coordinates

System, which resembles for instance thè generators

of a cone and thè set of circles lying normally to ge¬

nerators. The comparative morphology of a definite

sclerite can be treated by d’Arcy Thompson’s me-

thods. Difficulties arise with sets of sclerites and

bristles, particularly when one is faced to thè intro-

duction or to thè disparition of some of these ele-

ments. The problem is to insert smaller graphs

within larger ones, in order to see thè articulation

between thè successive levels, and this creates singu¬

larities, but nothing is really sure in thè preparation

of these coordinates systems integrating several dif¬

ferent description levels.

I carne back to thè text of d’Arcy Thompson, to

observe that probably he had himself encountered

problems in thè application of his method. D’Arcy

Thompson compared a series of more or less direct

ancestors of horses. The difficulties are implicit in le-

gends to thè fìgures representing thè simplest series

of transformations from thè skull of Hyracotherium

(Eocene) to that of Equus (contemporary horses)

through «various artifìcial or imaginary types, re-

constructed as intermediate stages», which are sup-

posed to represent thè direct line of descent. Skulls

of Mesohippus, Protohippus, Miohippus and Parahip-

pus are drawn for comparison with thè imaginary

skulls, but without their own curvilinear arrays. The

study shows that Mesohippus and Protohippus are not

far from being in thè direct line of descent from

Hyracotherium to Equus, whereas Parahippus cor-

responds to a somewhat divergent branch in thè

genealogy. If one tries to draw thè absent array for

Parahippus, it appears that strong locai distortions

are necessary for this skull. This is not due to thè fact

that thè array is in two dimensions and difficulties

would not be resolved with thè use of three-dimen-

sional coordinates systems. These difficulties could

be much stronger, if we had thè possibility to exa-

mine thè originai materials and thè accurate drawing

of suture lines of cranial bones.

It is worth remembering that comparative studies

of legs were also essential in most works on thè evo-

lution of horses, but d’Arcy Thompson did not re¬

present thè corresponding deformations, probably

for thè simple reason that several bones disappeared

in thè course of evolution, thè recent horses running

on limbs built from thè preferential development of

a unique finger. D’Arcy Thompson was aware of thè

limits of his theory, but he simply wrote:

We cannot fìt both beetle and cuttlefish into thè same fra-

mework, however we distort it ; nor by any coordinate transfor-

mation can we turn either of them into one another or into thè

vertebrate type.»

Actually this problem is stili present within thè

vertebrate groups, studied by d’Arcy Thompson

himself, and in small families such as Lamippids, thè

above-mentioned parasitic Copepods. Singularities

seem to be necessary in transformation grids and this

indicates that extreme continuous deformations in-

vented to fit any shape in thè same framework are

very suspect and thè main danger is thè blind appli¬

cation of computer programs created for that. It is

probable that many accurate morphologists, among

zoologists, botanists and paleontologists tried thè

d’Arcy Thompson method in its originai form, but

abandoned it. What is surprising is thè generai ab-

sence of comments, in several recent papers, on thè

difficulties inherent to this method.

Naturai grids and their singularities

More or less orthogonal arrays of fìbrils often exist

in thè skin of vertebrates and invertebrates. The two

main directions of these arrays generally lie at about

45° from thè long axis of thè animals. In worms such

as nematods, these fìbrils (mainly collagen) generally

form two families of helices, either left-handed or

right-handed. The skin is cylindrical and, within its

thickness, layers of left-handed helically wrapped fì¬

brils alternate with layers of right-handed ones.

Such cross-ply systems exist in thè integument of

most annelids and in several groups of vertebrates,

mainly in embryoes. Collagen is replaced by chitin

in arthropod cuticles, but fìbrils often form similar

networks, with two preferred orientations which

also stabilize at about ± 45° from thè long axis of

thè body.

For all these animals, thè preferential orientations

of thè fìbrous lattice of thè integument can be repre-

sented in projection onto thè external morphology

and this can be considered as a possible materializa-

tion of thè coordinates framework of d’Arcy Thomp¬

son. Since, it is convenient to keep longitudinal and

transverse coordinates in thè body and its appenda¬

ges (and for several simple geometrical reasons), it is

better to consider that thè curvilinear d’Arcy

Thompson framework is possibly obtained with thè

set of lines tangent to thè two normal bisectors of

these fibril orientations.

MORPHOLOGICAL SINGULARITIES AND MACROEVOLUTION

29

24

Figs. 23-27 - 23-26) D’Arcy Thompson’s transformations methods applied to a set of sclerites observed in thè first thoracic

appendages of four different species of Lamippe. 23) Lamippe rubicunda, thè sclerite named j is absent in Fig. 26 ( Lamippe

/aurei), whereas thè one called y seems to be absent from figures 24 and 26 ( L . aciculifera and L. /aurei). Sclerites a and 3

are particular to L. aciculi/era (fig. 24); 27) Schematic view of an articulation in a crustacean appendage, with two successive

cylindrical (or conical) sclerites (c.s.) and an arthrodial cuticle (a.c.). The lateral insertion of a bristle (not represented

itself) generates singularities indicated by two arrows.

i

30

Y. BOULIGAND

In thè case of nematods, with a regularly cylindri-

cal body, thè fìbrous network is formed by two fami-

lies of helices of equal pitch, which are right-handed

and left-handed and intersect at a Constant angle (réf.

in Picken). In generai, animai shapes are less simple

than cylindrical and fìbrils form singular arrange-

ments. This had been observed in thè dermis of sela-

cians, by Garrault (1937) and in tadpole embryoes by

Rosin (1946), whose pictures are reproduced in figs.

28 to 32. More recently, a series of micrographs were

obtained by a collaborator, L. Lepescheux (1988) in

skins of Annelids and we deduced thè models of fi-

gures 33 to 37.

The construction principle of these discontinuities

is similar to that of singularities introduced in La-

mippids, to apply thè transformations method (but

with different symmetries). We suggest (but have no

proof...) that such singularities could be a necess-

ary ingredient in thè theory of transformations and

that thè direct pictures obtained from microscopie

examination of thè integument of several species,

belonging to very different systematic groups, illu¬

strate a generai principle of morphogenesis and evo-

lution of shape, but now thè problem is to know

thè degree of generality of these singular arrange-

ments of fìbrils and to see how to build (if justifì-

100 firn

50 jrm

Figs. 28-32 - Fibrillar structure of thè basement membrane of thè epidermis of a tadpole of Bombinator (after Rosin,

1946). 28) Dorsal view. 29) Lateral view. 30) Ventral view. 31) Series of trigonal and pentagonal singularities in thè differen-

tiation area of thè gills. 32) Micrograph of a pair of singularities, with a trigonal symmetry on thè left and a pentagonal one

on thè right.

Y. BOULIGAND

31

able) maps of thè distribution of these singularities

at difTerent ages.

Some of these singularities show well defined po-

sitions with respect to thè anatomy, as can be seen

(fig. 28-30). Other singularities have a more random

distribution, and this seems to be thè case for those

observed in thè gill region of tadpoles (fig. 31). These

types of distributions are similar to those of small or-

gans in most living beings.

Orthotaxy, plethotaxy and cosmiotaxy

Certain organs can be homologized and be given a

name, on thè basis of having a particular position in a

linear series, for instance, as it is thè case for teeth in

mammals. Such organs were said to be orthotaxic by

Grandjean (1948) and are in Constant number, or say

that number variations are rare. On thè contrary, un-

distinguishable organs such as hairs cannot be ho¬

mologized, one by one, and their number show

strong variations between individuals. They are said

to be plethotaxic. There is a third situation called cos¬

miotaxy, corresponding to identical organs, ordered

into regular two-dimensional arrays, such as cilia in

Cibata (Protozoa) or in mussel gills, ommatidia in

compound eyes in arthropods, or fish-scales. In that

case also, there are strong variations in thè total

number of organs of this type. One-dimensional se¬

ries of identical (or almost identical) organs also exist

and well known examples are vertebrae in many fi-

shes and in snakes. This situation is similar to that of

cosmiotaxy, with variations of thè total number of

elements. (All Grandjean’s references will be found

in Travé and Vachon, 1975; his complete acarologi-

cal works were republished from 1972 to 1975; a se-

lection of references is proposed in Bouligand, 1989).

Singularities present in thè naturai grids of thè in-

tegument in various animals are either orthotaxic,

plethotaxic or cosmiotaxic, and therefore present a

common character with small organs such as bristles

and other formations of thè integument. We find es-

sential thè fact that certain singularities of thè natu¬

rai grids in thè integument can be homologized as

other organs can be (teeth and bones in mammals,

bristles and sclerites in arthropods). This fact is quite

naturai since thè presence of small organs as bristles

imply thè presence of singularities in thè fibrous grid

of thè skin. But certain singularities exist without thè

differentiation of associated organs.

Remarks on d’Arcy Thompsons’s position

relative to Darwin’s theory

D’Arcy Thompson’s methods of continuous trans-

formations represent a strong support to thè gradua-

list views of Darwin ( Natura non facit saltum), but

since their author himself observed some limits to

his theory, this was interpreted as an opposition.

D’Arcy Thompson is often considered as non-Dar-

winian (Edelman, 1992). Bookstein (1977) indicates

that «thè sturdy popularity of d’Arcy Thompson’s

book resides rather in its own unique method, a

quite non-Darwinian search for geometrie simplic-

ity...» The faets are that Darwin wrote a preface for thè

first published book by d’Arcy Thompson, a translation

of H. Miiller’s Fertilization of Flowers and, much later

on, d’Arcy Thompson was Darwin medalist of thè

Royal Society. The fact is also that d’Arcy Thompson

felt unsatisfìed with some points of Darwin’s theory,

but I suppose just as Darwin himself was about many of

his own conceptions. D’Arcy Thompson defines him¬

self very clearly his position, when he writes:

«It would, I dare say, be an exaggeration to see in every bone

nothing more than a resultant of immediate and direct physical

or mechanical conditions, for to do so would be to deny thè exis-

tence in this connection, of a principle of heredity... I maintain

that it is no less an exaggeration if we tend to neglect these direct

physical and mechanical modes of causation altogether and to

see in thè characters of a bone merely thè results of variations

and of heredity.»

In his book On growth and Form, d’Arcy Thomp¬

son presented a highly documented study, which can

be considered (it is my opinion) as a contribution to

Darwin’s theory, even if d’Arcy Thompson discussed

some paragraphs or sentences from thè Origin of Spe-

cies. An interesting example corresponds to thè fol-

lowing question asked by Darwin:

«There is no obvious reason why, for instance, thè wing of a

bat, or thè fin of a porpoise, should not have been sketched out

with all thè parts in proper proportion, as soon as any structure

became visible in thè embryo.»

D’Arcy Thompson indicated that a plausible an-

swer comes from what we cali today dimensionai

analysis and scale constraints. An engine which

works perfectly at a given scale does not do so at a

different one, because laws governing mechanisms

are not invariant with dimension and, as pointed out

by Galileo more than three hundred year ago, this

also applies to nature and living systems.

The very point which differentiates d’Arcy Thomp¬

son from Darwin is thè question of discontinuities

and this is clearly presented in thè last lines of his

book entitled On Growth and Form :

«In short, nature proceeds from one type to another among or-

ganic as well as inorganic forms; and these types vary according

to their own parameters, and are defined by physico- mathemati-

cal conditions of possibility. In naturai history Cuvier’s types

may not be perfectly chosen nor numerous enough, but types

they are; and to seek for stepping-stones across thè gaps is to seek

in vain, for ever.

This is no argument against thè theory of evolutionary desc-

ent. It merely States that formai resemblance, which we depend

on as our trusty guide to thè affinity of animals within certain

bounds or grades of kinship or propinquity, ceases in certain

other cases to serve us, because under certain circumstances it

ceases to exist. Our geometrical analogies weigh heavily against

Darwin’s conception of endless small continuous variation; they

help to show that discontinuous variations are a naturai thing,

that mutations -or sudden changes, greater or less- are bound to

have taken place and new type to have arisen, now and then. Our

argument indicates, if it does not prove, that such mutations, oc-

curing on a comparatively few definite lines, or plain alternative,

of physico-mathematical possibility, are likely to repeat themsel-

ves: that thè higher protozoa, for instance, may have sprung not

from or through one another, but severally from thè simpler

forms; or that thè worm-type, to take another example, may have

come into being again and again.»

These two last paragraphs give probably thè rea¬

son why d’Arcy Thompson is sometimes classified as

non-Darwinian. The opposition appears between

considerations which actually are two conjectures:

thè one proposed by Darwin that any complex organ

has been formed by numerous, successive, slight

modifications and thè one proposed by d’Arcy

Thompson, of thè absence of stepping stones across

thè gaps between main systematic types.

Darwin knew that important and sudden morpho-

logical changes observed under domestication or

under naturai conditions did not resist naturai selec-

tion and that fertility also involved continuity, at a

32

MORPHOLOGICAL SINGULARITIES AND MACROEVOLUTION

level which will be called, in modern terms, genomic

compatibility, what corresponds to only small diffe-

rences between alleile genes.

I am less tempted to follow d’Arcy Thompson in

his conjecture for several reasons. The introduction

of discontinuities in a curvilinear coordinates frame-

work, such as those considered above and represent-

ed on fìgures, can increase considerably thè hearing

of thè method. Pairs of singularities can be generated

continuously (this is mainly a matter of defìnition)

and this is illustrated in fig. 39. In a certain way, this

continuous birth of discontinuities is analogous to

speciation which also can be a continuous process,

even if thè result is a discontinuity: thè existence of

well separated species. Now, it remains difficult to

know thè extent of thè transformations theory, re-

handled with such topological changes. It is probably

a new tool to compare thè main types of vertebrates.

The question as to whether this principle affords

continuous Solutions to pass for instance from a bee-

tle to a cuttlefìsh is far from being tackled but, even

extreme, such transformations cannot be excluded.

Figs. 33-38 - Various singularities were observed by L. Lepescheux in Annelid cuticles. Instead of being interwoven, as

admitted by Rosin, fibrils form separated and superimposed sheets, even in thè very neighbourhood of these singularities.

36 and 37) These patterns are associated with shapes which are not applicable onto a piane (saddle point and bump).

38) Semicontinuous formation of a pair of singularities in a set of aligned Fibrils (a, b, c). Correlative differentiation of a pair

of singularities in a d’Arcy Thompson’s grid.

MORPHOLOGICAL SINGULARITIES AND MACROEVOLUTION

33

Liquid crystals and thè orìgin of naturai

coordinate grids

Biological analogues of liquid crystals

I have shown in several works (see ref. in Bouli-

gand, 1978) that thè organic matrix of skeletal tissues

often presents a continuous structure which is that of

a particular helicoidal liquid crystal, but is stabilized

by several types of Chemical cross-links. There are

many examples of these non fluid analogues of li-

quid crystals in biological Systems. Liquid crystalline

self-assembly of collagen was obtained recently by

Giraud-Guille (1992) and works on similar processes

with cellulose and chitin are in progress at McGill

University, with Revol et al. (1992, 1993). I studied

thè singularities of these liquid crystals and of their

stabilized forms, mainly in thè crab exoskeleton. The

structure of these singularities is accessible, but thè

reai problem is that of their distribution relative to

thè anatomy and to thè external morphology.

Grids in thè integument of worms, insects and am-

phibian tadpoles, mentioned above, come from thè

stabilization of liquid crystalline secretions (collagen

or chitin), with preferred orientations due to various

mechanical constraints under thè control of cells.

There are examples of parallelism between cytoske-

letal elements and just secreted extracellular fìbrils,

when they adopt certain preferential orientations,

different from those followed in pure self-assembly

processes (ref. in Bouligand and Giraud-Guille,

1985). This has been observed in fish-scales and in

plant celi walls. We suppose that similar relations

between epidermal cytoskeleton and extracellular

matrices exist in thè insect cuticles and in thè verteb¬

rate compact bone. Many cross-ply structures appear

under these conditions and continuous passages are

often observed from purely helicoidal systems,

which are analogues of liquid crystals, to these cross-

ply systems, with preferential orientations.

Singularities in liquid crystals and in their

biological analogues

The distribution of molecular orientations in li-

quid crystal varies continuously and is often repre-

sented by vector fields. It follows that singularities in

such systems resemble those usually considered in

vector fields, but very different types of singularities

are also observed. The spontaneous arrangements of

molecules around these discontinuities lead to a rich

world of morphologies and similar organizations

exist in biological analogues of liquid crystals (ref. in

Bouligand, 1981).

It is well known that one of thè parameters govern-

ing crystal growth, is thè density of these very special

singular lines named screw-dislocations. These dis-

locations are involved in thè growth of enamel apati¬

te crystals and that of thè nacre in molluscan shells,

for instance. The screw character is also present in

singularities considered above, observed in different

skin networks whose structure recali thè d’Arcy

Thompson curvilinear grids. Similarly, liquid crys¬

tals show various lines of discontinuity, called dislo-

cations, focal lines and disclinations, which also play

important ròles in thè assembly and in thè generai

morphology of these phases. These singularities can

be observed directly in stabilized tissular structures,

such as thè arthropod cuticle for instance, which dif-

ferentiate by liquid crystalline self-assembly. On thè

contrary, in compact bone, such singular lines prob-

ably exist, but are extremely difficult to recognize

and to identify in thè microscope. The problem of

their distribution is beyond me in this material, but

indirect methods could be considered.

The problem is to study, in liquid crystals and in

their biological counterparts, thè deformations intro-

duced by a given density of singularities, when these

latter are easily observed (some common liquid crys¬

tals and demineralized crab cuticle for instance).

This is a geometrical problem for microscopists, with

no obvious answer at thè present time. If some gen¬

erai laws can be deduced, then a new approach

would be possible in thè comparative studies of ani¬

mai shapes, but much work is stili necessary to pre¬

pare research in this field.

With thè introduction of singularities in compara¬

tive morphology, we have to look to macroscopic

characters corresponding to long range rearrange-

ments of fìbrils around these singularities, whose

core however is generally observed at thè ultrastruc-

tural level. The various topological rehandlings of

tissues very often leads to such ultrastructural dis¬

continuities, which generally lie outside of thè exa-

mined surfaces or sections. These basic construction

patterns come from self-assembly processes and

from a series of celi activities.

Plesiomorphic ultrastructures

Diffìculties with thè concept

of synapomorphy

Strict reversibility and parallelism are considered

as unlikely, when thè characters under consideration

are defined with a very large amount of information

and represent something as a signature of thè com¬

mon origin of a group of species. This comes from

simple considerations on probabilities. Long series

of independent events never reproduce and never

give long palindromes. This leads to introduce a par-

simony principle in thè construction of cladograms.

However, a strict application of this principle ignores

that evolutionary events are far from being inde¬

pendent and there are many examples of parallelism

hardly compatible with this parsimony principle

(Gosliner and Ghiselin, 1984). There are many poss¬

ible causes for thè existence of similar characters bet¬

ween related species: symplesiomorphies, synapomor-

phies, different forms of parallelism and among

them: parallel selection influencing physiologically

analogous structures, parallel selection influencing

homologous structures, parallelism due to common

inherited factors causing incomplete synapomorphy

(Saether, 1979, 1983).

In thè case of thè above considered parasitic cope-

pods, we fìrst believed that thè axopodlike aciculae

corresponded to a synapomorphy and de Zulueta

considered this trait as essential for classifìcation.

We stili think that this character is useful in thè locai

systematics of thè family of Lamippids, but we gave

up thè idea of a synapomorphy, when more or less

related structures were discovered in some species of

ascidicolous copepods. Other characters such as

morphology of sclerites and distribution of bristles

34

Y. BOULIGAND

showed more combinations with thè presence or ab-

sence of aciculae, than those acceptable in a purely

cladistic conception, with a strict application of thè

parsimony principle. At thè present stage of know-

ledge, we cannot choose between two possible hypo-

theses: 1. The first Lamippids beared aciculae and

this character was already present in thè most recent

ancestors common to Lamippids and these ascidi-

colous copepods. 2. An opposite hypothesis is that

expression of aciculae is a threshhold dependent

character, which appears at preferential sites (furca,

bristles) and sometimes on thè whole surface of

thè parasite, if there is a large overstepping of thè

threshold.

This leads us to admit that certain characters are

less rare than we can think at first and could be lat-

ent, waiting for a propitious situation, genetic or not,

to be expressed. Then, what we believed to be a locai

synapomorphy transforms into a symplesiomorphy

defìned by a character shared by a large group of spe-

cies, at thè genotype level for instance, but not ne-

cessarily at thè phenotypic level. Some groups of

species are able to express thè character in thè syste-

matic group, but this character does not justify a cla¬

distic regrouping. Let us cali this situation an under-

lying symplesiomorphy. This situation is very dose to

that called underlying synapomorphy by Saether

(1979), since thè considered characters concern a

narrow group. Here we prefer to speak of underlying

symplesiomorphy, because we consider thè expres¬

sion of genes common to a much larger group than

thè examined family. Such underlying symplesio-

morphies are known experimentally, since many in-

sects have two pairs of wings, whereas flies have only

one, thè posterior pair being replaced by small «hal-

teres». We learnt, some years ago, that some genetic

experiments suffìce to restore thè expression of a

normal pair of posterior wings. We want to suggest

that this situation also exists naturally in very large

systematic groups, well defined by certain Constant

characteristics, whereas other traits are expressed

here and there in thè group, but are probably more

Constant in thè genotype.

Expressed symplesiomorphies

The group of Spiralia (Annelids, Molluscs, Rota-

torians, some Platyhelminths, etc.) is defined by thè

oblique orientations of thè first celi cleavages in thè

egg. Another character which is rarely taught is that

most muscles are obliquely striated, thè distribution

of myofìbrils leading then to helical or to double-obli-

que patterns (fìgs. 40-42). This character seems to be

Constant and is observed in all Annelids, Molluscs,

Rotatorians, fiat and round worms, Bryozoa, Bra-

chiopods, etc. There are however examples of per-

pendicularly cross-striated muscles in Molluscs and

Annelids, for instance in thè fast portion of thè ad-

ductor of thè scallop and also in thè proboscis of cer¬

tain Polychaetes (Annelids), but in all these animals

most muscles are obliquely striated or smooth (refi

in Bouligand, 1966c). Obliquely striated muscles are

absent in all other groups (Coelenterates, Echino-

derms, Tunicates, Vertebrates). The oblique stria-

tion of at least a part of muscles seems to be an ex-

cellent example of plesiomorphy for thè Spiralia

sensu lato (and an excellent synapomorphy, when

Spiralia are compared to thè other groups). There is

also a special kind of myosin, thè main protein of

thick filaments in muscles, which is also a good cha-

racteristic of thè whole group of Spiralia.

Underlying symplesiomorphies

We shall now consider another character of Spi¬

ralia, which seems to be generai, but not always

expressed. Two groups of Annelids (Polychaetes and

Oligochaetes) are defined by several characters, an

essential one being thè presence of bristles regularly

distributed along metameres. These bristles show

very Constant ultrastructures in thin section (fìg. 43).

Each bristle is produced in a follicle, which is a fin-

ger-like invagination of thè epidermis. A highly diffe-

rentiated celi, present at thè bottom of thè invagina¬

tion, is called chaetoblast, since it seems at first view

responsible of secretion of thè whole bristle, made of

chitin principally and some associated proteins. The

secretion occurs at thè basis of a set of parallel micro¬

villi, which control thè bristle formation, which pro-

ceeds by pure accretion at this level. New microvilli

are differentiated, whereas others are dedifferentiat-

ed in thè course of thè secretion, whose intensity

also varies and can be stronger between certain mi¬

crovilli; this produces bending and other morpholo-

gical characters of bristles, used in thè recognition of

species. Some lateral cells of thè follicle are also

involved in thè secretion process, by adding new

materials, possibly by intussusception, or simply

by external accretion (Bouligand, 1967). Phenolic

tanning also Comes from this lateral contribution

(Lehy, 1966).

Structures closely related to Polychaetes bristles

were observed over thè mantle surface of some ce-

phalopods: Kòlliker organs of thè hatching Octopus

(Brocco et al., 1974), in some Brachiopods, Lingula

for instance Storsch and Welsch (1972), cylindrical

spicules in Chitons (Prenant, 1923), in Pogonophora

(Gupta and Little, 1970) etc. In all these examples, as

in Polychaetes, also in Oligochaetes and Echiurida,

thè secretion of each bristle is guided by one celi dif¬

ferentiated with microvilli: thè chaetoblast, and

there are lateral productions due to follicular cells.

These very characteristic structures are generally ab¬

sent in molluscs, but reappear in certain genera, such

as Octopus in Cephalopods and Chiton among Placo-

phora, with various distributions and at precise sta-

ges in thè life cycle.

Aciculae of Lamippids, thè parasitic copepods

considered above, are very different from these brist¬

les observed in several groups of Spiralia, since their

structure is rather analogous to that of axopods in

Actinopoda. However, thè distribution principle of

this type of organ seems to be similar. Copepod aci¬

culae are generally absent, but when expressed, they

are gathered at thè extremity of non-sclerifìed brist¬

les, and, in certain cases they appear on thè whole

surface of thè body. In thè case of Spiralia, when

bristles are expressed, they are either concentrated in

parapods (Polychaetes), but they can cover a large

area of thè body within thè egg, before hatching, in

certain cephalopods. Such resurgences of a character

hidden in thè genome are plausible, but have never

been fully demonstrated to occur in naturai condi-

tions. The confìrmation of such a hypothesis could

represent a severe difficulty in thè application of cla¬

distic methods. The problem in this method is to re-

MORPHOLOGICAL SINGULARITIES AND MACROEVOLUTION

35

Figs. 39-41 - 39) General aspect in thè photonic microscope of thè contracile apparatus of helically or double-obliquely

striateci muscles in Spiralia (mainly Annelids, Molluscs, but also in fiat and round worms. Brachiopods, Bryozoa, Vesti¬

mentifera, etc); a and b: relaxed state; a' and b': contracted state.

Fig. 40 - General ultrastructure of obliquely striated myofibrils (Z: Opaque element to which are attached thin actin

filaments a; m: thick paramyosin filaments interdigitated with thin actin filaments; p: cross-bridges linking thick and thin

filaments).

Fig. 41 - The ultrastructure of this muscle is replaced in thè generai pattern of doublé striation (Dt, D2) and according

to thè section piane, one gets aspects which are those observed in smooth muscles, in cross-striated muscles and in ob-

lique-striated muscles. F and f: thick and thin myofilaments; A: zone of interdigitated thick and thin filaments; I: zone

with Z elements and attached thin filaments.

36

Y. BOULIGAND

cognize, when a character presents two different Sta¬

tes, which one is primitive and which one is derived.

Another question is simply to have a clear definition

of thè two States of a unique character.

The difficult determination of thè time

arrow in phylogeny

Geologists were thè first to recognize situations in

sediments and in rocks, clearly indicating for two

events from a remote past which one preceded thè

other one. Developmental biologists have a direct

evidence of thè embryo transformations and of their

order in time. On thè contrary, evolutionary biolo¬

gists are faced to numerous problems to get such evi¬

dence about thè time arrow.

The available criterions

The agreement between scientists in evolutionary

biology comes mainly from thè connected character

of thè trees they build. These minimal graphs repro¬

duce thè genealogies of species with more or less ac-

curacy, and thè knowledge of thè time arrow at one

point of thè tree often suffice to orientate a large part

of it. The problem is however to build these minimal

graphs and to fmd some good examples which allow

one to recognise which characters are ancient and

which ones are new.

The available information on thè arrow of time

in evolution comes from paleontology and from

considerations about complexity and differentia-

tion. The concept of molecular clock, even with its

inherent difficulties, can be very useful. Compari-

sons between ontogeny and phylogeny are not al-

ways accepted, but in this domain thè concept of

organ priority and its measurement, introduced by

Grandjean (1942) is useful and is related to hierar-

chies observed between embryonic inductions and

between thè expression of genes involved in deve-

lopment (Bouligand, 1989). This is a to wide problem

to be considered here.

Regression and multiplication

There is another type of criterion observed by

Grandjean, from his studies on phylogeny and onto¬

geny of mites, mainly thè Oribatids and he deduced

certain rules. One of them concerns thè arrangement

of small organs like bristles in thè external morpho-

logy. The evolution leads to a progressive numerical

regression in one or several series of orthotaxic organs,

which can be followed, more or less suddenly, by a

multiplication of these small organs, presenting then

an anorthotaxic situation (pletho-or cosmiotaxy). Si-

milar evolutions are plausible in different lineages of

Vertebrates: thè number of vertebrae was reduced,

certain vertebrae being progressively specialized, in

many Amphibians and Reptiles. Then, multiplica-

tions of vertebrae appeared, according to a highly

uniform model, possibly in Apods, in Ophidians and

in thè slow-worm, Anguis fragilis, for instance. The

situation could be similar for thè teeth of Mammals,

whose number was progressively reduced in several

groups, whereas thè differentiation between inci-

sors, canins and molars which was reinforced, but

sudden multiplications of teeth appeared in some

«edentate» mammals and in Cetaceans (Odonto-

cetes) for instance; teeth were replaced by multi¬

ple «whale-bones» in other Cetaceans, thè whales

(Mysticetes).

In our Copepod family, that of Lamippids conside¬

red above, thè appendages in thè genus Linaresia

show thè maximum reduction of bristles known in

thè whole family, and there is simultaneously a

strong multiplication of small papillae of thè integu-

ment in thè same cephalothoracic region, but our

study of this family is not as well documented as that

of Grandjean dealing with Oribatids.

Comparison with crystals (solid or liquid)

If true, thè scenario of evolution considered by

Grandjean probably applies to singularities observed

within naturai grids of thè integument of numerous

species and of their embryoes. The concepts of

ortho-, pletho-and cosmiotaxy can be applied to thè

singularities represented in Rosin drawings (fìgs. 28

to 31). For instance each eye presents a lateral

pentagonal singularity and this corresponds to an

example of orthotaxy, whereas thè pentagonal and

trigonal singularities, observed in thè area corres-

ponding to thè future gills, are more or less randomly

distributed and this corresponds to an example of

plethotaxy. As quoted above, one finds in liquid

crystals (and also in true crystals), various rearran-

gements of thè network, which correspond to singu¬

larities (also called dislocations or defects), whose

distribution is called texture (Bouligand, 1981). The

texture geometry depends on conditions prevailing

during crystallization and on thè nature of various

other constraints. In such systems, there are disloca¬

tions occupying higly «functional» positions, whe¬

reas others are more or less randomly distributed.

This term «functional» can appear as exaggerated,

but this is not always thè case since, in true crystals,

there are «screw-dislocations», whose presence acce-

lerates thè cristallization process. To come back to

thè living systems, these singularities exist in many

tissues and constraints leading to various textures

come mainly from a celi control.

Diversity and macroevolution

This work is a review of thè main difficulties en-

countered in my own studies to connect a set of

morphological data into a coherent evolutionary in-

terpretation. One of thè obvious conclusions is that

animai diversity remains very difficult to appreciate,

this being shown by thè study of Lamippids, this

small and apparently homogeneous family of parasit-

ic Copepods, which however shows extreme exam¬

ples of macroevolution. Recent hypotheses in pa-

leontological literature give also an evidence of thè

difficulty to appreciate diversity and this deserves a

discussion. There is a second conclusion, which is

that, beside heterochrony, there is another mecha-

nism of macroevolution, that of heterotopy. This

term is used mainly in medicai Sciences and means

thè abnormal displacement of an organ or a tissue

and seems be rare in thè evolutionary context, but

could mean a change in location of well identifìed

parts of thè body. If small genetic changes are able to

modify thè order in thè ontogenic time of essential

MORPHOLOGICAL SINGULARITIES AND MACROEVOLUTION

37

42

ve

m

rv.

^ fifa ° ' r

3% o: ^ q ' o v* ?■

. . c i^'èo

• ' CI O /.V/r?-’ ’V. Q-- .

° /■? M st'** ’o Ut

o .'- ?,Vo o u

" — 7pi.oó 0,;, *

II ' ° q - e &

-“"' .*7': : -*7

^/v. *v**. * ; ■ ;£• .'-f ■■ -' •*"'• *•■

^ y^ C) Qs J j- *>

■ i o

*?# c>- ..<;

- ...

0 « ■■■*■/ '■" < ' vOc ° 5

C>> ' 0 *-JU* o * ?JQ&

■ S* . ■/}&„* -sJ cPV'TO

0. „ Q~ o q_, 12^0

ì^ra-^~^71TT^~à Ire..

,•,•-■••■ o

-k&rtT'

4^Év--- •

’Jir-*.- ' •— aSai

n

Fig. 42 - General ultrastructure of an Annelid bristle. A 90° sector of this more or less cylindrical secretion is represented;

thè apical region of thè chetoblast, with its nucleus Nc, form a set of parallel microvilli (mv), which are a guide to chitin se¬

cretion vesicles (cv); other secretory activities are observed in lateral cells, with their nuclei (NI) and their vesicles (cl) at

thè level of thè tips of microvilli; these lateral secretion vesicles often form prismatic patterns (n); thè two membranes of

thè nuclear envelope often show large separations (rn); at a distance of microvilli there is a free space (L) separating thè

bristle from lateral cells of thè follicle; very usuai celi organelles are observed: various celi junctions (d), ergastoplasm (e)

Golgi apparatus (g), mitochondriae (m), polyribosomes (pr) and free ribosomes (r), various types of vesicles: (ve, vd). Brist-

les with similar or closely related ultrastructures are found in isolated species or in some groups of Spiralia.

38

Y. BOULIGAND

developmental events, one can expect that other

genetic changes can modify thè domains, in thè mor-

phological space, where some characters are expres-

sed, and also thè morphology of these characters. A

change in time is often correlated with a change in

space and conversely. So, thè idea of heterochrony

suggests that its spatial counterpart, heterotopy,

could be an evolutionary mechanism.

The difficulty to estimate diversity

Recent articles deal with remarkable fossils disco-

vered ninety years ago and propose, from their restu-

dy, that main systematic groups appeared during a

relatively short geological period, thè cambrian

explosion. Despite thè high quality of these fossils

and some ones recently discovered, it is difflcult to

understand how several authors conclude that such

observations demonstrate a sudden macroevolu-

tion occuring in many groups, with no equivalents in

later periods. Main phyla and classes are probably

very ancient, but this is established from thè study of

numerous fossils collected by successive generations

of paleontologists and not from a particularly rich

fauna discovered in some very old sedimentary for-

mations.

The question can be reasked differently. How to

estimate for instance thè extreme morphological

changes observed in parasitic copepods, and particu¬

larly those within this narrow family of Lamippids,

and then to compare them to those considered in

these cambrian organisms? These copepods possibly

existed and diversified in thè cambrian seas, but ac-

tually we have no accurate information. Extremely

large variations also are common in many other

groups of invertebrates. How to measure thè ampli-

tude of such variations in living species and to com¬

pare them to those in extinct faunas? Methods do

not really exist in thè present state of knowledge, but

some indices are possibly available and, apparently,

they are never considered in these papers.

An accurate knowledge of diversification in living

beings and its chronology will come from detailed

analyses of genomes and of many phenotypic charac¬

ters, but this stili exceeds our present capabilities,

and perhaps will for a very long time. I suppose that

thè overestimate of diversity in a fossil fauna could

be related to thè fact that most zoopaleontologists

work on bones and shells, which are homogeneous

structures in vertebrates and molluscs. The knowled¬

ge of diversity comes more from neontological stu-

dies (zoology and botany), than from paleontology.

In my opinion, thè gap separating paleobotany from

botany is less important than thè one between paleo-

zoology and zoology.

Heterochrony and heterotopy

Small causes produce important effects, when

conditions are not far from those of an instability and

this can be thè origin of discontinuities appearing in

a continuous context. Examples are known in irre-

versible thermodynamics, in phase transitions for in¬

stance, and this conception has been generalized in

thè frame of a topological approach of dynamical Sys¬

tems (Thom 1972). This is a generai principle in

physics, which certainly applies to many situations in

biology and possibly in species evolution. This idea

of continuously evolving parameters controlling a

change, with more or less sudden effects, was poss¬

ibly present in thè mind of Schiaparelli and also Vol¬

terra (Scudo, 1991, 1994).

Simple genetic changes can modify thè develop-

ment rate of a given organ, and thè result is a new

shape of thè whole body. This corresponds to hete¬

rochrony (displacement, acceleration or retardation

of an ontogenetic process within thè generai context

of development). What was considered in our exam¬

ples (from copepods to vertebrates) corresponds to

similar changes, possibly generated by small genetic

variations, but instead of a change considered along

thè time axis, thè relevant axes now are those of thè

coordinate grids, these cartesian coordinate frames

which are made curvilinear, with thè possible intro-

duction of singularities.

Such topological rehandlings are obvious things

for certain microrganisms: for instance, thè Radio-

larian skeletons showing thè symmetries of thè Pla-

tonic bodies, described by Haeckel (1887) in one of

thè Challenger Monographs. The useful pictures are

reproduced in thè book of d’Arcy Thompson in his

fìg. 340. Some ornaments show that thè represented

species are very closely related, but since they have

thè symmetries of different regular polyhedrons (oc-

tahedral, dodecahedral, icosahedral), there are no

continuous passages between these phenotypes,

whereas thè genetic differences could be small.

A change in thè number of facets in Radiolarians

can be compared with another discrete variation,

that of thè number of fìngers. This latter has general-

ly a genetic origin, which is however much less than

thè differentiation of a new species. It is not exclud-

ed that some individuals among populations of such

polyhedral Radiolarian show thè symmetries of a dif¬

ferent polyhedron. I do not read literature enough in

this domain to know whether or not is has been ob¬

served. However, strong heterotopic variations are to

be expected within this group. It appears also that

thè introduction of coordinate frames on such mor-

phologies would resemble thè representations of

harmonic functions onto a sphere, with thè corres-

ponding singularities and polyhedral symmetries.

The passage from one solution to another one is dis-

continuous, but could be parametrized continuously

within a rather simple model.

Let us recali that regular polyhedral morphologies

are very common in flower pollens and similar dis¬

crete variations occur among closely related species.

Polyhedral morphologies also exist in many viruses,

but passages to different symmetries are generally

excluded in that case, but there is possibly a sort of

exception, in certain giant T4 bacteriophages with

much longer head than usuai.

Topological rehandlings are regular processes in

ontogeny and in phylogeny of animals and involve

thè introduction of singularities, whose existence is

demonstrated in some materials, but much more in¬

formation is necessary to introduce these concepts in

thè very foundations of developmental and compa¬

rative morphology. Singularities have long range

effects or not. One obviously observes thè interme¬

diate situations. The importance of deformations

produced by a dislocation in a crystal is called thè

«mass» of thè defect by crystallographers. Similar pa¬

rameters could be introduced in biomorphology but

this seems to be to early.

MORPHOLOGICAL SINGULARITIES AND MACROEVOLUTION

39

Conversely, thè concepts of orthotaxy, plethotaxy

and cosmiotaxy, which come from biomorphology,

could be introduced in crystallography, since disloca-

tions are distributed either randomly, with a more or

less Constant density (plethotaxy), or form regular

lattices (cosmiotaxy), form definite patterns called

textures, where many singularities occupy definite

places and can be given a name.

Grandjean observed that series of events are arro-

wed in thè evolutionary time. Similarly, in crystals, it

can be easily verified that textures present irrevers-

ible types of evolution, since hysteresis is a generai

rule in thè behaviour of defects or dislocations. One

can fìnd examples in liquid crystals showing how re-

gression in thè number of singularities leads to or¬

thotaxy. If thè singularities number decreases below

a certain threshold, thè texture either disappears or is

conserved but higly rehandled, if some parameter is

changed, for instance temperature variation or intro-

duction of an external fìeld. Similar changes in thè

biological context could correspond to a strong in-

crease in thè number of cells in a given tissue. Ortho¬

taxy is then followed by anorthotaxy. In thè same

line of thought, let us recali that screw-dislocations

can be considered as «functional», since their ròle is

recognized as essential in crystal growth.

Well known examples of topological rehandling

are observed in Drosophila, with those processes cal¬

led transdetermination, thè mutation Antennapedia

for instance, leading to thè production of two more

or less complete legs in thè place of thè two anten-

nae. Such animals cannot resist naturai selection. On

thè contrary, to pass from a polyhedral shape to ano-

ther one for a Radiolarian is not an obvious handi¬

cap. When topological rehandlings of biomorpholo¬

gy are not incompatible with survival, there is a

plausible place for a large evolutionary step. Such sit-

uations are probably rare, but not excluded, and thè

two positions of Darwin and d’Arcy Thompson will

possibly represent thè two interesting pòles of discus-

sions in thè future developments of research on ma-

croevolution.

Conclusion

Self-assembly is a major process in thè genesis of

supramolecular structures in biological systems and

is closely related to crystal growth. Among these

morphogenetic mechanisms, generally considered as

working at lower levels of organization, there is a

particular self-assembly based on liquid crystalline

phases, which can be stabilized into supple but mor-

phologically defìned structures. Liquid crystals show

long range orders with remarkably diversifìed pat¬

terns. The fluidity of liquid crystalline secretions

leads to regular shapes, which can be rehandled by

resorption and resecretion controlled by cells. The

ordered fluids form an essential interface between

cells and thè extracellular matrices, on which are

based thè main characters of morphology.

Among thè patterns arising from liquid crystalline

self-assembly and controlled by celi activities, there

are sets of extracellular fìbrils forming networks

visibly related to thè d’Arcy Thompson’s grids, con¬

sidered in thè continuous shape transformations in

evolution and development. These naturai grids

show thè presence of singularities, those possibly

corresponding to difficulties arising from thè use of

d’Arcy Thompson methods by pure continuous de-

formation of thè coordinate network. The apparent

distance between Darwin’s and d’Arcy Thompson’s

conceptions about continuity Comes possibly from

thè need to introduce these singularities, but we

indicated that their introduction within a regular

lattice can intervene by creation of singularities

pairs, which can be considered as continuous. In

physics, there are transitions which are first order,

second order, and fìnally very soft. The creation of

this kind of singularities can be considered as a very

soft process...

The problem is that our personal exploration of

some biological species and of liquid crystals, biolo¬

gical and non-biological, does not suffice to really

propose generai principles, since much remains to be

done in thè examination of singularities in cells and

tissues, simply at a purely methodological level, and

results in this fìeld will need to be replaced in thè

context of molecular genetics, to be somewhat con¬

sistei in thè studies on macroevolution.

Acknowledgements - 1 wish to thank several collea-

gues who have read thè manuscript and proposed very

useful remarks, references and copies of articles, parti-

cularly Dr. M. T. Ghiselin and Dr. F. Scudo. I wish also

to thank thè Milan group, namely Professor G. Pinna

and Dr. P. Arduini.

BIBLIOGRAPHY

Bookstein F. L., 1977 - The study of shape transformations after

d’Arcy Thompson. Mathematica I Bioscience, 34: 127- 219.

Bookstein F. L., 1981 - Coordinate systems and morphogenesis.

In: Morphogenesis and Pattern Formation, T. G. Connely ed

ai ed., Raven Pr., New-York.

Bouligand Y., 1966a - Recherches récentes sur les Copépodes

associés aux Anthozoaires. In: The Cnidaria and their Evo¬

lution, W. Rees ed. Symp. Zool. Soc. London, 16: 267-306

Acad. Pr.

Bouligand Y., 1966b - Le tégument de quelques Copépodes et

ses dépendances musculaires et sensorielles. Mém. Muséum

Hist. Nat., Nouvelle Sèrie, A, Zoologie, 40, (4): 189-206.

Bouligand Y., 1966c - La disposition des myofilaments chez

une Annélide Polychète. J. Microscopie, 5: 305-322.

Bouligand Y., 1967 - Les soies et les cellules associées chez

deux Annélides Polychètes. Etude en microscopie photoni-

que à contraste de phase et en microscopie électronique.

Zeitschrift fiir Zellforschung und mikroskopische Anatomie,

79: 332-363.

Bouligand Y., 1978 - Biological anlogs of liquid crystals. Solid

State Physics, Suppl. 14, 259-294.

Bouligand Y., 1981 - Defects and textures in liquid crystals. In

Dislocations in Solids, Nabarro, F.R.N. ed., North- Holland,

5: 299-347.

Bouligand Y., 1989 - La priorité des organes selon F. Grand¬

jean: une articulation précise entre ontogenèse et phyloge-

nèse. Geobios, Mém. spécial, 12: 79-91.

Bouligand Y. and Giraud-Guille, M.-M., 1985 - Spatial

organization of skeletal tissues: analogies with liquid

crystals. Biology of Invertebrates and Lower Vertebrates

Collagens, A. Bairati and R. Garrone eds., Plenum Pubi.:

115-134.

Brocco S.L., O’Clair R. M. and Cloney R. A., 1974 - Cephalo-

pod integument: thè ultrastructure of Kòlliker’s organs and

their relationship to setae. Celi Tissue Res., 151: 293- 308.

Darwin C., 1859 - The origin of Species. J. Murray, London.

Edelman G. M., 1992 - Bright Air, Brilliant Fire, On thè Matter

of Mind. Basic Books.

40

Y. BOULIGAND

Garrault H., 1937 - Structure de la membrane basale sous-épi-

dermique chez les embryons de sélaciens. Arch. Anat. Micr.,

33: 167-176.

Giraud-Guille M.-M., 1992 - Liquid crystallinity in condensed

type I collagen Solutions. J. Mol. Biol., 224: 861-873.

Grandjean F., 1942 - Les méthodes pour établir les listes de

priorité et la concordance de leurs résultats, Comptes Rendus

Acad. Sci. Paris, 214: 729-733.

Grandjean F., 1948 - Sur la distribution spatiale des organes

d’un groupe homéotype. Comptes Rendus Acad. Sci. Paris,

227: 10-13.

Grandjean F., 1972-1976 - Compiete acarological works. 7 vols.,

van der Hammen, ed., W. Junk B. V.

Gupta B. P. and Little C., (1970) - Studies on Pogonophora, 4:

Fine structure of thè cuticle and thè epidermis. Tissue & Celi,

2: 637-696.

Haeckel E., 1887 - Challenger Monogr., Radiolaria.

Hipeau-Jacquotte R., 1986 - A new cephalic type of presumed

sense organ with naked dendritic ends in thè atypical male of

thè parasitic copepod Pachypygus gibber (Crustacea). Celi

Tissue Res. (1986), 245: 29-35.

Lehy T., 1966 - Mise en évidence d’un système de tannage quino-

nique au niveau des soies chez Sabellaria alveolata (L.), Po-

lychète sédentaire. Ann. Histochimie, 11: 71-78.

Lepescheux L., 1988 - Spatial organization of collagen in annelid

cuticle: order and defects. Biology of thè Celi, 62: 17-31.

Picken L., 1960 - The Organization of Cells and other Orga-

nisms. Clarendon Press Oxford, republished 1962.

Prenant M., 1923 - Remarques sur les processus de formation

des spicules cylidriques chez les chitons. Bull. Soc. Zool. Fr.,

48: 150-156.

Revol J. F., Bradford H., Giasson J., Marchessault R. H. and

Gray D. G., 1992 - Helicoidal self-ordering of cellulose mi-

crofibrils in aqueous suspension. Int. J. Biol. Macromoi, 14:

170-172.

Revol J. F. and Marchessault R. FL, 1994 - Chiral nematic or-

dering of chitin crystallites. Internat. J. Biol. Marcomoi, (in

press).

Rosin S., 1946 - Uber Bau und Wachstum der Grenzlamelle des

Epidermis bei Amphibien Larven. Analyse eine orthogona-

len Fibrillarstruktur. Rev. Suisse Zool., 53: 133-201.

Scudo F. M. , 1991 - Morphology and systematics, before and

after Schiaparelli. Riv. Biol., B. Forum, 84: 130-135.

Scudo F. M., 1994 - Schiaparelli Giovanni Virginio (1835-1910),

Dictionnaire de l’Evolution et du Darwinisme, P. Tort

(Dir.). Presses Universitaires de France, Paris (in press).

Storch V. and U. Welsch, 1972 - Uber Bau und Entstehung

der Mantelrandstacheln von Lingula unguis L. (Brachiopo-

da). Z. wiss. Zool. Leipzig, 183: 181-189.

Thom R., 1975 - Structural Stability and Morphogenesis (translat-

ed by D. H. Fowler). Benjamin, New York.

Thompson d’Arcy W., 1917 - On Growth and Form. Cambridge

Univ. Pr.

Trave J. et Vachon M., 1975 - Francis Grandjean 1822-1975

(Notice biographique et bibliographique). Acaralogia, 17: 1-19.

Zulueta A. de, 1961 - Boi. Roy. Soc. Esp. Hist. Nat., B., 59: 227-230.

Y. Bouligand: Institut de Biologie Théorique, EPHE, 10, rue André-Bocquel, 49000 Angers FRANCE

et Centre de Biologie Cellulare, CNRS, 67, rue M.-Giinsbourg, 94200 Ivry/S. FRANCE

Systematic Biology as an Historical Science

Memorie della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano

Volume XXVII - Fascicolo I - 1996

Mikhail A. Fedonkin

The Precambrian fossil record: new insight of life

Abstract - The study of thè Precambrian fossil record, especially active in thè second half of 20th century, reveals thè

phenomena that could not be predicted on thè basis of thè Phanerozoic experience of thè classical palaeontology. Among

major revelations there are astounding antiquity of life, domination of microscopie, in particular, prokaryotic organisms

during thè most part of Earth history, cruciai role of thè biota in thè steady but radicai change of thè global environment,

dramatic restructuring of thè global ecosystem during thè late Neoproterozoic accompanied by thè rise of thè eukaryotic

trophic pyramid and very late appearance of thè metazoans.

According to historians of Science, about 2.000

species of fossils plants and 25.000 species of extinct

animals had been described by 1850, i.e. nine years

before thè fìrst edition of Darwin’s «Origin of Spe¬

cies» was published. Practically all fossil species that

had been described were from Europe.

Recently about a quarter of a million of thè fossil

species have been described from all thè continents.

More than 99 per cent of thè fossil taxa have been

described from thè Phanerozoic.

Paleontology dealing with long period of time has

revealed phenomena which are impossible to obser-

ve directly. Human life, and even historical time are

too short to allow us to notice and to recognise slow

and steady trends in thè biosphere masked by nu-

merous reversible fluctuations. That is why thè ideas

of cyclic, static and linear time of thè world have

been equally competing through thè whole history of

human culture (Grunbaum, 1969). Actually we do

not have actualistic methodological instruments that

would allow us to see difference between thè long-

term events and fluctuations if their duration ex-

ceeds human historical experience.

The fossil record, being thè integrative result of

long term processes and fluctuations, decreases thè

noise from thè latter and, otherwise, represents more

prominently thè long and irreversible trends and

events. That is why it was paleontology which gave

thè fourth dimension, namely thè Time Arrow, to

thè recent model of Nature. The idea of biological

evolution was thè most fundamental and valuable

discovery of classical paleontology. Evolutionary ap-

proach has subsequently spread through most other

areas of thè naturai Sciences.

The introduction of thè radiometrie dating of

rocks has revealed thè great age of our planet, i.e.

4. 5-5.0 billion years against 4-5 thousand years

what was generally believed according to thè Chris¬

tian tradition (interpretation of Bible) and even

against thè 100 million years, an estimation based on

thè comparison of thè amount of salt in thè world

ocean and annual input of salt by rivers (Burchfield,

1990).

Radiometrie dating, fìrst invented early in thè 20th

century by Bertram Boltwood, a Yale physicist, has

led not only to thè discovery of thè great age of Earth

but also to thè fact that thè Phanerozoic makes about

1/9 of geologie history in its entirety. This fact meant

that almost two centuries of classical paleontology

were devoted to thè study of a rather small portion of

thè history of life. And even though thè Phanerozoic

is thè best documented part of life history, it is stili

thè tail of thè whole story.

Generations of geologists and paleontologists con-

sidered thè Pre-Phanerozoic rocks as being non-fos-

siliferous. For example, thè whole sequence of thè

Riphean sedimentary rocks accumulated between 1.6

and 0.6 billion years ago and exposed in thè Ural

Mountains in Russia for many years was referred to

as «ancient dumb formations» because these rocks

seemed to be «mute» in respect of life. Apparent ab-

sence of fossils in thè Precambrian rocks was thè rea-

son for thè name Cryptozoic (from Greek «cryptos»

that means concealed, covert, unrevealed) for thè

greatest (about 85%) and thè early portion of thè his¬

tory of life.

The Precambrian fossil record became thè subject

of intensive study relatively late in comparison with

thè age of paleontology as a special scientific discip¬

line, i.e. effectively after 1960 although thè pioneer

works can be traced far back to thè beginning of thè

century. Before thè middle of our century thè term

«paleontology of thè Precambrian» sounded strange

and even later this term was rejected by some pa¬

leontologists on thè grounds that many objects in thè

Precambrian fossil record have uncertain nature

while others, for instance stromatolites, are in fact

remnants of peculiar geobiocoenoses and not thè

fossil remains of thè organism. Nevertheless during a

few last decades a series of thè fundamental discove-

ries has been made in thè Precambrian fossil record,

which dramatically changed our understanding of

life’s history and life as a phenomenon of a longer

time retrospective.

It was P. S. Laplace (1749-1827) who noticed that

an appeal to thè vast extent of time and space gives

thè possibility for discovering new classes of pheno¬

mena. His statment has found a brilliant confìrma-

tion in thè whole experience of classical Phanerozoic

paleontology.

An appeal to thè far longer history of thè Precamb¬

rian life has led to thè discovery of new faets of criti¬

cai importance, and actually to new insights about

life. It turned out that thè Phanerozoic experience of

42

MIKHAIL A. FEDONKIN

paleontology doses not exhaust thè whole diversity

of biohistorical phenomena. However, on thè way

down to thè Precambrian fossil record paleontolo-

gists have met many methodological problems con-

nected partially with thè phenomena which do not

have actualistic or Phanerozoic counterparts and

with situations which do not allow one to use thè

uniformitarian approach. In a sense, during most of

thè Precambrian geological history thè Earth was

quite a different and «unfamiliar» planet. All these

problems have affected thè systematics of thè pa-

leontological objects as well.

One of thè usuali difficulties of thè Precambrian

paleontology is an identification of thè true biolo-

gical or biogenic objects from what is called «pseu-

dofossils» i.e. thè non-biogenic objects of uncertain

nature morphologically resembling fossil or living

organisms. One should note that thè question of

how to distinguish thè living objects from thè non-

living ones on thè basis of purely morphological

characters is not quite trivial even for some recent

forms (like some viruses or bacteria, especially in

a latent phase of life activity). But this problem

becomes really difficult in many cases of paleonto-

logical practice in particular when thè specialists

deal with objects of a simple morphology which can

be observed in thè non-biogenic objects as well

(Thompson, 1942).

The matter is that in addition to thè pure morpho¬

logical characters which can be used as thè criteria

for identification of thè live object, recent organisms

demonstrate an ability for locomotion, growth, re¬

production, metabolic activity, etc., i.e. thè charac¬

ters which are impossible to observe or to judge in

dealing with thè fossil organisms. The concept of

biogenecity is poorly developed for fossil objects.

Purely morphological criteria turned out to be inade¬

quate for systematics both at thè low taxonomic level

and at thè level of higher taxonomic categories (in-

cluding life itself if one should consider it as a taxon)

in thè oldest part of thè Precambrian fossil record.

That is why along with thè morphological criteria

based on thè similarity of problematic fossils with

living or known extinct organisms one should take

into account thè taphonomic spectrum of thè fossils

as well as thè minerai, organic, molecular or isotopie

traces of life activity, probable place in a biohistorical

or evolutionary sequence, chronological probability,

position in thè paleoecosystem etc. (Hofmann, 1972;

Sokolov and Fedonkin, 1988).

The study of thè Precambrian fossil record is con-

nected with some other peculiarities in addition to

thè very long time intervals and uncertain nature of

many fossil objects mentioned above.

First of all, thè biotic diversity of thè Precambrian

fossil record looks very low if compared with thè

Phanerozoic one. Precambrian fossils have been col-

lected from more than 3.000 localities all over thè

world, but slightly more than 1.300 fossil taxa at thè

genus level have been described up to now (Hof¬

mann, 1988). Some critically inclined paleontologists

evaluate thè number of thè «reai» taxa in thè Pre¬

cambrian as somewhere between 500 and 900. Chro-

nologically and stratigraphically thè distribution of

thè Precambrian fossil localities is very uneven.

About 1-5 localities per every 100 million years are

usuai for thè Early Proterozoic, and about 10-25 loca¬

lities per every 100 million years of geological history

are typical for thè Late Proterozoic. The Archean

fossil record looks far more poor. For example,

slightly more than 20 localities of stromatolites are

known from thè whole Archean. Thus thè number of

thè sites where thè fossils could be preserved decrea-

ses with thè growing age of thè rocks.

Another circumstance is that macroscopic orga¬

nisms appeared relatively late and even among those

microfossils which represent thè procaryotic world

thè paleontologists identify just thè large bacterial

cells, in particular thè cyanobacteria, while thè most

of other groups of thè procaryotes do not yet have a

fossil record because of their very small celi size (for

instance, thè whole Kingdom Archaeobacteria).

In spite of an exponential growth of paleobiologi-

cal information from thè Precambrian we stili meet

some serious difficulties in identifying thè whole

range of biological phenomena known from thè Pha¬

nerozoic fossil record. There are a few reasons for

this: 1) poor morphological characters and uncertain

nature of many fossil groups; imperfect classification

especially among thè procaryotes where pure mor¬

phological characters have very low taxonomic

value; 2) low biological diversity at thè species level,

which is thè most effective for thè purpose of de-

tailed biostratigraphy and evolutionary modeling;

3) lack of data on thè evolutionary lineages for thè

most of thè Precambrian groups of organisms; 4) low

precision of thè biostratigraphic division and telecor-

relation of thè Precambrian strata if compared with

Phanerozoic counterparts; 5) change in time of thè

environmental biotic and abiotic factors which

strong influence on thè taphonomic processes (such

as an oxygenization of thè sediment, development of

heterotrophy, bioturbation, thè rise of thè filter feed-

ers, etc. see Fedonkin, 1985, 1987, 1992).

In contrast with thè classical paleontology of thè

Phanerozoic thè study of thè Precambrian history of

life is predominantly oriented to thè world of thè

procaryotes which dominated in thè most of envi-

ronments during thè major portion of thè history of

thè biosphere. The rise of thè eucaryotes essentially

wiped off thè picture of thè procaryotic world though

they continue to play a great role in most biological

processes. Competing with bacteria for some nu-

trients and habitats, forcing thè procaryotes out of

numerous biotopes, utilising thè by-produets of pro¬

caryotic life activity and consuming thè bacterial bio¬

mass as food eucaryiotic organisms have changed

thè world and thè fossil record as well.

On thè other hand, in thè process of thè symbiotic

origin of thè eucaryots accompanied by thè colonisa-

tion of thè host celi by procaryotic organisms thè lat-

ter have lost their individuality while they lost their

free mode of life. So part of thè procaryotes disap-

peared just because they became thè organelles of

eucaryotic cells.

And last but not least, eucaryotes have essentially

contributed to thè global change of environments fa-

vorable for thè life activity and fossilisation of proca¬

ryotic organisms.

A great advantage of thè Precambrian fossil record

in spite of thè diffìculties mentioned above is an ab-

sence of a developed trophic pyramid above thè net¬

work of procaryotic biogeochemical interactions.

This circumstance opens up a unique possibility to

read undisturbed paleontological, sedimentological

and biogeochemical signals from thè procaryotic

THE PRECAMBRIAN FOSSIL RECORD: NEW INSIGHT OF LIFE

43

ecosystems of thè Precambrian biosphere during

most of its history. Conservatism of thè procaryotes

in their morphological, ecological and biochemical

aspects, relative simplicity and determinate character

of their biogeochemical ties and reactions make it ea-

sier to decode thè geochemical and sedimentological

signals of thè Precambrian procaryote-dominated

biota especially in thè Archean and Early Proterozoic

parts of thè geological record.

Paleontology of thè Precambrian deals with diver¬

se microfossils, thalli of megascopic algae, metazoan

body fossils and bioturbations, stromotolites and

some other biosedimentary structures, biogenic mi-

nerals, kerogens, organic films, biomarkers and

other organic chemofossils. Along with thè pure pa-

leobiological methods thè geobiological approach

(review in Fedonkin, 1993, 1994b, in press) has been

actively developing during last two decades.

According to thè geobiological approach thè bio¬

sphere should be considered an integrated System of

interacting biotic and abiotic components where life

acts as thè most active part of thè System (Vernadski,

1926). Recent models of Precambrian climates, atmo-

sphere and ocean chemistry, sedimentary processes,

etc. do include thè biota as an active factor control-

ing those processes (Lovelock, 1979; Charlson et al.,

1987; Chaloner and Cocks, 1989; Derry et al., 1992).

On thè other hand, thè study of those processes

which are usually beyond thè scope of paleontology

(for instance, thè isotope record of carbon and sul-

fur) casts additional light upon thè biota and envi-

ronment in thè Precambrian (Zavarzin, 1984; Hol-

land, 1984, 1992; Kasting and Ackerman, 1986; Hayes

et al., 1992a,b; Schopf and Klein, 1992 and references

therein). The limited lenght of this paper makes me

concentrate mainly on paleontological objects — on

thè Precambrian fossil record as it recently come to

look after a few decades of intensive study.

The Precambrian fossil record demonstrates that

during thè major portion of thè history of life thè mi¬

croscopie organisms, in particular procaryote, have

dominated in all thè habitats. Precambrian microor-

ganisms usually are preserved a) as mummifìed or

organic-walled microfossils, and b) as minerai pseu-

domorphs (silicified ones are thè most common in

thè chert nodules or inside thè silicified stromatoli-

tes and bacterial mats). Being heterogenous by their

nature (eubacteria, lower eucaryotic algae, lower

fungi, protozoans, cysts, eggs and egg cases etc.) thè

microfossils demonstrate three important trends

through out thè Precambrian fossil record, namely

thè growth of morphological diversity, increasing in¬

dividuai celi size and thè tendency to coloniality

(Schopf, 1992 a, b,c).

Celi size analysis and thè study of thè internai

structure of thè microfossils were thè major approa-

ches to thè problem of thè nature and taxonomic di¬

versity of thè oldest Precambrian microorganisms.

None of thè approaches gave definite arguments.

Dramatic discussions of thè nature of thè «dark

spots» inside some of thè microfossils (nucleus, col-

lapsed protoplasm, gas vacuole or an organelle?)

have led to a number of additional approaches, e.g.

thè study of thè postmortem degradation of recent

microorganisms in vivo and in vitro, experiments

on thè artificial fossilisation of thè microorganisms,

actuopaleontological and taphonomic research etc.

(Golubic and Hofmann, 1976; Knoll, 1985 a; Pierson,

1988; Krylov, Tikhomirova, 1988; Rothschild and

Mancinelli, 1990).

These approaches were supplemented by thè com¬

parative study of thè ecology of thè recent bacterial

communities and their Precambrian counterparts

(Castenholz et al., 1992). The structure of thè com¬

munity and thè kind of environment were supposed

to give thè key to thè problem of thè nature of thè

Precambrian microfossils. In particular, it was de-

monstrated that thè recent bacterial communities of

sabkhas, marshes and lagoons of thè arid climatic

zones might be considered as analogs for thè globally

dominated ecosystem through most of Precambrian

life history (Awramik, 1984; Knoll, 1985 b).

Later on it carne to be understood that thè wide

range of thè procaryotic tolerance and their asto-

nishing biochemical diversity essentially exceeds thè

dominant environmental parameters of thè recent

biosphere. This observation has led to an idea that

thè space of biochemical diversity, thè tolerance li-

mits and thè physico-chemical parameters favorable

for thè most intensive reproduction in some recent

procaryotes may be indicative of thè environments

which existed on Early Archean Earth, i.e. during thè

periods of thè rise of thè procaryotic world (Knoll

and Bauld, 1989).

Thus, two actualistic approaches mentioned above

have given rise to non-actualistic models of thè Pre¬

cambrian biospheres. And again, here one can see

thè importance of thè data on Precambrian environ¬

ments for adequate paleobiological reconstructions

and research on thè systematics of thè oldest fossils.

The most notable evidence of thè microbial life

activity in thè Precambrian are thè stromatolites.

These biosedimentary structures fìrst appear as early

as 3.5 billion years ago and became widespread in

Early Proterozoic as thè dominant shallow water

landscape of carbonate platforms. The abundance

and morphological diversity of thè stromatolites in-

creased rapidly during Proterozoic and reached thè

maximum at about 1.0 billion years ago (Walter and

Heys, 1985).

Though thè stromatolites are in fact thè remnants

of biogeocoenoses they are referred to by Latin

names to identify thè formai morphological «genera»

and «species» and are arranged into thè formai Sys¬

tems according to their generai shape, mode of

branching, microstructure etc. The nature of thè

stromatolite morphological characters and of thè

stromatolite taxa is not well understood. However

thè taxonomy of stromatolites became an important

instrument to search thè Precambrian life history.

Distinct changes in thè stromatolite assemblages

through thè Precambrian fossil record discovered

empirically by thè paleontologists of thè Russian

biostratigraphic school (Maslov, 1960; Krylov, 1963,

1975), may reflect both intrinsic factors (such as

changes in thè structure and composition of thè mi¬

crobial communities, biological and biochemical in-

novations of thè stromatolite-building procaryotes)

and extrinsic factors (such as change in thè chemistry

of thè ocean and thè atmosphere, global climate and

paleogeography, appearance of thè eucaryotic groups

competing with or feeding on thè stromatolite bacte¬

rial communities).

Stromatolites as thè globally dominating biogenic

landscape of thè Proterozoic shallow water environ¬

ments demonstrate marked decline in their abun-

44

MIKHAIL A. FEDONKIN

dance and diversity after 1.0 billion years ago and es-

pecially dramatic after 700 million years ago. The

possible cause for thè stromatolite decline might be:

a) negative effect of thè new evolved grazing and

burrowing metazoans (Awramik, 1971; Walter and

Heys, 1985); b) appearance of eucaryotic algae com-

peting with thè cyanobacteria for nutrients, habitats

and light (Monty, 1974); c) major low-stands in thè

sea level (Gebelein, 1976); d) negative effect of thè

growing concentration of biogenic oxygen upon thè

bacterial stromatolite-building communities (Kry-

lov, 1988); e) decreasing carbonate of thè sea water

during thè Late Proterozoic (Grotzinger, 1990); f) ch¬

inate change, in particular African Glacial Era and its

paleogeographic and geochemical consequences

(Semikhatov and Raaben, 1993). In fact, all these hy-

potheses may be complementary.

Along with thè stromatolites and rare remnants of

thè carbonate algae which are indicative of carbonate

biomineralization in thè Precambrian there are other

biominerals which are thè mineralogical evidence of

thè other groups of organisms, though their celi (or

body) fossils are unknown. Biomineralization is a ra-

ther usuai phenomenon of life. About 60 minerals

are produced by representatives of all five kingdoms

of thè organic world and biomineralogical diversity is

far from being exhausted (Lowenstam and Weiner,

1989).

Biominerals which have a unique shape of their

crystals as well as other physico-chemical properties

can easily be distinguished from their abiogenic

counterparts and may be used as markers of certain

groups of organisms in thè geological record.

At least one-third of thè known biominerals are

produced by thè procaryotes but thè biochemical

possibilities of thè bacteria are far broader than thè

geochemical diversity of recent naturai environ-

ments. Given this fact we hope to discover a greater

diversity of procaryotic biominerals in thè Precamb¬

rian. Recently thè first steps in this direction were

taken. Isotopie composition of sulphide minerals

may indicate thè presence of biologically induced

biomineralization as far back as 2.7 billion years ago

(Monster et al., 1979). Direct evidence of thè presen¬

ce of magnetobacteria about 2.0 billion years ago is

thè recently discovered biogenic magnetite crystals

in Lower Proterozoic rocks (Kirschvink, 1992). The

earliest produets of life activity of thè encrusting

manganese bacteria have been discovered in depo-

sits 1.6 billion years old (Muir, 1978). The oldest evi¬

dence of carbonate biomineralization is represented

by thè slightly calcifìed cyanobacteria in rocks 1.0 bil¬

lion years old (Riding and Voronova, 1982, 1984).

The last decade has been marked by success in thè

separation, identification and taxonomic interpreta-

tion of biologically meaningful organic compounds

(or biomarkers) from Precambrian kerogens and hy-

drocarbons (Hahn, 1982; Hoering, 1987; Summons

and Walter, 1990; Ourisson, 1990). A generai trend in

thè biomarker time-distribution demonstrates their

limited diversity in thè Early-Middle Proterozoic and

increasing diversity towards thè end of thè Precamb¬

rian. This approach makes it possible to construct

simple «molecular phylogenetic trees» and to identi-

fy thè appearance of thè major known groups of thè

organisms in thè fossil record. For example, pentacy-

clic triterpane hydrocarbons represent thè molecular

remnants of thè eubacteria, some sterols represent

eucaryotes, and some acyclic isoprenoids are indica¬

tive of thè archebacteria (thè kingdom which did not

leave any morphological traces in thè fossil record).

There have also been discovered some unusual

kinds of biomarkers, indicative of thè groups of mi-

croorganims of a hight taxonomic rank which existed

in thè Proterozoic and became extinct later (Sum¬

mons and Walter, 1990).

The study of thè oldest biomarkers from thè

well preserved Proterozoic sediments may indicate

that microbial communities of thè Middle and Late

Proterozoic included not only cyanobacteria and

phototrophic eucaryots but, possibly, heterotrophic

protozoans. There were organisms resembling rec¬

ent dinoflagellates among thè Late Proterozoic

plankton.

The increasing abundance and diversity of megas-

copic fossils observed through thè Proterozoic fossil

record seems to reflect thè rise of multicellularity,

which could appear repeatedly and independently in

all kingdoms of thè organic world. In some groups

multicellularity might be genetically preserved due

to thè selective advantage of large body size and indi¬

viduai biomass or because celi specialisation.

The oldest megascopic carbonaceous fossils,

which are approximately 2.0 billion years old, may

stili represent thè flattened remains of microbial co-

lonies or bacterial mat fragments. Some appearance

of cellular structure is extremely rarely observed.

Morphologically more complex carbonaceous fossils

with some possible anatomical details appear in thè

rocks of about 1.4 billion years old but they are be-

coming more complex and diverse after 0.8-0. 9 bil¬

lion years ago. Most of these fossils are interpreted

as eucaryotic algae though some of them are con-

sidered as probable colonial procaryotes, fungi or

even metazoans (Hofmann, 1992).

Of criticai importance may be thè recent discovery

of a megascopic, spirally coiled cylindrical alga,

Grypania, in rocks 2.1 billion years old (Han, 1991;

Han and Runnegar, 1992). The fossil is interpreted as

thè oldest eucaryotic photosynthetic autotrophic

organism.

Undoubtedly metazoan body fossils and trace fos¬

sils (or bioturbations) first appear in Vendian rocks

about 620 million years old which is extremely late

compared to thè age of life on Earth. Most of thè

metazoas appeared abruptly after thè great Varange-

rian Glaciation and spread rapidly all over thè globe

during thè vast post-glacial transgression of thè seas

over thè continents.

Astounishing peculiarities of thè oldest known an¬

imate are: a) their large body size (up to 1 meter and

more so they look gigantic compared with thè small

shelly fossils of thè early Lower Cambrian); b) gene-

rally an absence of a minerai skeleton in thè majority

of animate; c) high diversity oflife forms; d) high dif-

ferentiation at thè level of a high taxonomic rank, i.e.

remarkable diversity of thè body plans including

some unusual ones unknown or normally rare in

later metazoans; e) low diversity at thè species level

(monotypic genera dominating); f) domination of

Radialia or Diploblastica, i.e. thè animate of thè coe-

lenterate grade of organisation in thè fossil assem-

blages; g) widespread metamerism (true segmenta-

tion) and pseudosegmentation among thè forms

which may be interpreted as Bilateria or Triploblasti-

ca (Fedonkin, 1987).

THE PRECAMBRIAN FOSSIL RECORD: NEW INSIGHT OF LIFE

45

Interpretation of thè Vendian metazoan body fos-

sils known as thè Ediacara fauna (Glaessner, 1984)

has met numerous methodological difficulties for

number of reasons, e.g. unusual taphonomic cir-

cumstances, poor fossil record of thè Phanerozoic

soft-bodied invertebrates (few forms to compare),

predominance ot forms with «strange» body plans

(problematics or forms of uncertain systematic po-

sition), and an absence of data on thè Pre-Vendian

metazoans. Comparison of Ediarca fauna with

recent soft-bodied invertebrates is not very easy

because of thè great evolutionary distance that se-

parates them. All these aspects put thè Precambrian

metazoans in a position of an apparent (but illuso-

ry) phylogenetic isolation. Examples of thè evolu¬

tionary ties between thè Vendian and Cambrian

faunas are in fact more numerous than one could

suppose some years ago (Conway Morris, 1993;

Fedonkin, 1994a).

Although thè first specimens of thè Precambrian

metazoans were collected in Namibia in 1908-1914

(Gurich, 1929) it took decades to prove thè Precamb¬

rian age of thè fauna (Sprigg, 1947, 1949; Glaessner

and Daily, 1959; Glaessner and Wade, 1966). Since

thè time of Darwin, naturalists were puzzled by thè

apparent absence of metazoan remains in thè Pre¬

cambrian fossil record. Darwin himself considered

an absence of data on thè ancestors of thè Cambrian

fauna as a strong and disturbing argument against his

theory of thè gradualistic origin of species. Attempts

to explain thè apparent absence of thè metazoan fos¬

sil record below thè Cambrian strata did not seem

convincing to Darwin himself (see chapter X of thè

«Origin»).

This situation provided psychological preparation

for thè (chronologically) first approach that was de-

veloped for thè interpretation of Precambrian meta¬

zoans. The fossils were considered thè remains of in¬

vertebrates belonging to thè same high rank taxa as

known Phanerozoic animals (including recent ones).

Other psychological aspects of this approach are

based on thè opinion, whish dominated for a long time

among paleontologists, that thè high rank System

of thè invertebrates seems to be thè same from

Cambrian to recent time. The extremely poor fossil

record of soft-bodied animals in thè Phanerozoic

made thè paleontologists look through thè diversity

of thè recent metazoans for comparison with thè Pre¬

cambrian ones. Such a comparison had to be done,

but along with paying attention to thè prevailing

body plans and thè peculiarities of morphology in

norm, one must pay no less attention to thè small

relict groups, to unusual morphological phenomena,

and even to thè teratology of thè invertebrates to

fìnd thè whole range of morphological possibilities.

The norm demonstrates a more narrow spectrum of

characters but affects our work as systematists rather

strongly.

According to thè first approach thè Precambrian

fauna should be placed into thè following taxa: Phy-

lum Coelenterata (classes Hydrozoa, Anthozoa, Scy-

phozoa, Conulata, medusae of uncertain systematic

position and problematic Petalonamae), Phylum

Annelida (class Polychaeta), Phylum Arthropoda

(superclass Trilobitomorpha or Chelicerata), Phy¬

lum Pogonophora, Phylum Echiurida, as well as

some forms of uncertain systematic position even at

thè level of thè phylum (Glaessner, 1984).

The chronologically second approach has pointed

out thè dissimilarity of thè Vendian invertebrates to

their recent conterparts (Fedonkin, 1983). For practi-

cally all species of Ediacara fauna one can point out

characters that are in disagreement with thè groups

of recent invertebrates with which they have been

compared. Comparative body pian analysis of thè

Vendian body fossils, with special attention to their

symmetry as thè result of thè basic growth pattern, to

thè preservation, and to thè mode of life has led to a

different view of thè System and thè early evolution

of metazoans in thè Precambrian (Fedonkin, 1985,

1987, 1992, 1994a). In particular, three new classes of

thè coelenterates were established (Cyclozoa, Inor-

dozoa and Trilobozoa), a new Phylum Proarticulata

(with thè classes Dipleurozoa and Vendiamorpha),

and new arthropod class Paratrilobita (Fedonkin,

1985, 1990).

The third approach underlines an unusual tapho-

nomy and architecture of thè Vendian body fossils

considering most of them as representatives of thè

non-metazoan Kingdom Vendobionta (Seilacher,

1989). Sandy exoskeletons of an extinct group of

botom-dwelling sea anemones (Psammocorallia)

and thè trace fossils represents «true» metazoans

(Seilacher, 1990). Criticai analysis of thè concept

of Vendobionta has been published elsewhere

(Gehling, 1991, Fedonkin, 1992, 1994a, Conway Mor¬

ris, 1993).

Though thè System of thè Vendian body fossils is

under an intensive discussion thè key arguments in

favor of their metazoan nature are being received

from taphonomic and paleoecological study, and

from thè comparative promorphological (Bauplan)

analysis of these fossils and their later counterparts.

What are thè major revelations of life in thè light

of thè Precambrian fossil record?

1. The Phanerozoic fossil record embraces less

than 15 per cent of life history. The ages of Earth and

life are comparable. This fact returns our attention to

thè old idea of panspermia and to thè statement by

V.V. Vernadski that «life is geologically eternai».

Taking into account thè preservational aspect of

thè Precambrian fossil record (thè older thè deposits

thè less paleobiological information is preserved)

and thè ecosystem principle of thè life maintaining

(from thè very early moment thè life should exist as

an ecosystem uniting thè organisms with thè differ¬

ent trophic and biogeochemical functions) we

should talk about thè appearance rather than thè ori-

gin of life on Earth. One cannot rule out thè possibil-

ity that thè question on thè origin of life might be

posed incorrectly. The paleontology of thè Precamb¬

rian revives this problem though its resolution may

be beyond thè scope of paleontology.

2. During thè major portion of life history thè

procaryotic ecosystems have dominated absolutely

in thè most of thè habitats. However, neither mor-

phologically nor ecologically have thè procaryotes

changed much during 3.8 billion years since they

first appeared in thè fossil record. This may be parti-

cularly true for thè cyanobacteria which have a pre¬

servational potential that is higher than that of other

procaryotes because of their larger celi size and their

ecological peculiarities.

3. The history of thè biosphere can be subdivided

into two parts. The earlier and longer period of time

was marked by thè dominance of conservative bacte-

46

MIKHAIL A. FEDONKIN

rial ecosystems and by graduai and steady changes in

thè abiotic parameters of thè environment. The envi-

ronmental change was essentially produced by thè

biota. The later and shorter aeon is characterised by

thè rapidly evolving eucaryotic organisms and by thè

relatively stable abiotic parameters of thè environ¬

ment controlled by thè biota.

4. A two-stage structure of thè global biota consist-

ing of a conservative and stable procaryotic «founda-

tion» and an extremely changeable eucaryotic

«building» or «epistructure», was effectively formed

during thè Late Proterozoic. The eucaryotic trophic

pyramid was built above thè pre-existing network of

biogeochemical interactions between thè microbial

communities. This additive phase in thè evolution of

thè global ecosystem was relatively short. The sub-

stitution of thè individuai members in thè eucaryotic

trophic hierarchy became thè major process in thè

subsequent history of thè global ecosystem which

retained its principal structure.

5. The world of diverse eucaryotes is in fact an epi-

phenomenon on thè procaryotic ecosystems. Thus,

evolution in a Darwinian sense as well as thè phylo-

geneses seem to be relatively late phenomena of thè

life history. The phylogenetic tree as a symbol of

irreversible and divergent mode of historical deve-

lopment reflects thè late and shorter part of life

history which was predated by longer periods of

mosaic or network «evolution».

6. Though thè phylogenetic roots of thè eucaryo¬

tes go as far as 2.0 billion years ago these organisms

did not play an essential role in thè global ecosystem

untili thè Neoproterozoic. For a long period of

time since thè moment of their appearance thè euca¬

ryotes seemed to stay in thè limits of their primary

biotopes.

7. The primary biotopes for eucaryotic cells could

be thè microenvironments with sharp geochemical

(and/or light and thermal) gradients and conse-

quently with different procaryotic populations close-

ly spaced. The symbiogenetic origin of thè eucaryots

was in fact thè process of thè miniaturization of thè

pre-existing procaryotic ecosystems dowm to thè

size of thè celi.

8. In spite of thè incredible tollerance of thè proca-

ryotes to a wide variety of thè environmental factors

and their ability rapidly to restore an optimal popula-

tion density they were forced out as thè dominants

from most of their habitats by thè eucaryotic orga¬

nisms at thè end of thè Proterozoic. Eucaryotes have

opposed their ability to evolve at thè species and eco¬

system levels, their stupefyng diversity, more active

metabolism and larger individuai biomass. But what

is more important is that thè eucaryots have created

longer trophic chains. More complex ecosystems

turned out to be more economica! energetically.

9. The relative simplicity of trophic Systems, and

thè determinate and conservative character of thè

biogeochemical and reproductive reactions of thè

procaryotes to thè abiotic factors of thè environment

make it methodologically easier to decode thè bio-

genie signals from thè Precambrian fossil record of

thè procaryots than from thè Phanerozoic one. Being

masked by thè eucaryotic epistructure thè Phanero¬

zoic world of thè procaryotes remains obscure. Clas-

sical Phanerozoic paleontology is traditionally

oriented to thè eucaryotes mainly because of their

high preservational potential, great diversity and

evolutionary change (i.g. thè factors important for

biostratigraphic purposes). However, one should

take into account that thè rise of thè eucaryotes was

thè cause of thè destruction and deformation of thè

procaryotic fossil record.

10. An actualistic approach to thè interpretation of

thè Precambrian procaryotic communities and their

habitats leads to thè non-actualistic model of thè glo¬

bal environment.

Acknowledgements - I am grateful to Prof. Mi¬

chael T. Ghiselin, Prof. Francesco Scudo and Prof.

Giovanni Pinna, thè organizers of thè workshop Bio-

logical Systematics as a Historical Sciences in Milan

for thè possibility to discuss thè problems outlined in

this paper in a highly intellectual and stimulating en¬

vironment, as well as for their acute questions and

valuable comments. I appreciate very much thè more

detailed discussion of thè problems of thè Precamb¬

rian paleozoology with Prof. Alberto Simonetta.

REFERENCES

Awramik S. M., 1971 - Precambrian columnar stromatolite di¬

versity: reflection of metazoan appearance. Science, 174:

825-827.

Awramik S. M., 1984 - Ancient stromatolites and microbial mats.

In Cohen Y., Castenholz R. Z. and Halvorsen H. O. (eds).

Microbial Mats: Stromatolites. Allan R. Liss, New York,

N.Y.: 1-22.

Burchfield J. D., 1990 - Lord Kelvin and thè age of thè Earth.

The University of Chicago Press, Chicago and London: 267

pp.

Castenholz R. W., D’Amelio E., Farmer J. D., Barker

Jorgersten B. B., Palmisano A. S., Pierson B. K. and

Ward D. M., 1992 - Modem mat-buiding microbial commu¬

nities: methods of investigation and supporting data. In:

Schopf J. W and Klein C. (eds.). The Proterozoic Biosphere.

A Multidisciplinary Study. Cambridge University Press. Cam¬

bridge: 202-229.

Chaloner W. G. and Cocks L. R. M., 1989 - Biota and pa-

leoatmosphere. Journal of thè Geological Society, 46 (1):

145-146.

Charlson R. G. Lovelock G., Anmdreae M. O., Warren S. G.,

1987 - Oceanie phytoplankton, atmospheric sulphur, cloud

albedo and climate. Nature, 326 (6114): 655-661.

Cloud P. E. and Semikhatov M. A., 1969 - Proterozoic stromato¬

lite zonation . American Journal of Sciences, 261: 1017-1061.

Conway Morris S., 1993 - Ediacaran-like fossils in Cambrian

Burgess Shale-type faunas of North America. Palaeontology,

36, part 3: 593-635.

Dery L. A., Kaufman A. J. and Jacobsen S. B., 1992 - Sediment-

ary cycling and environmental change in thè Late Proterozo¬

ic: evidence from stable and radiogenic isotopes. Geochimica

et Cosmochimica Acta 56: 1317-1329.

Fedonkin M. A., 1983 - Organic World of thè Vendian. (Transac¬

tion ofthe Institute of Scientific and Technical Information,

Itogi Nauki i Tekhniki). Stratigrapy and Paleontology, 12:

128 pp. (In Russian).

Fedonkin M. A., 1985 - Precambrian metazoans: thè problems of

preservation, systematics and evolution. Philosophical Tran-

sactions of thè Royal Society of London. Part B 311: 27-45.

Fedonkin M. A., 1987 - Non-skeletal Fauna of thè Vendian and

Its Place in thè Evoultion of Metazoans. Transactions of thè

Paleontological Institute. Nauka, Moscow, 226: 175 pp. (In

Russian).

Fedonkin M. A., 1990 - Systematic description of thè Vendian Me-

tazoa. In: Sokolov B. S. and Iwanowski A. B. (eds.). The Ven¬

dian System. Paleontology. Springer Verlag, Berlin, 1: 71-120.

THE PRECAMBRIAN FOSSIL RECORD: NEW INSIGHT OF LIFE

47

Fedonkin M. A., 1991 - Biosphere: fourth dimension. Priroda, 9:

10-18. (In Russian).

Fedonkin M. A., 1992 - Vendian faunas in thè early evolution of

Metazoa. In: Lipps J. H. and Signor P. W. (eds.). Origin and

Early Evolution of thè Metazoa. Plenum Press, New York:

87-129.

Fedonkin M. A., 1993 - Paleobiology of thè Precambrian: on thè

way to a synthesis. In: Sokolov B. S. and Iwanowski A. B.

(eds.). Fauna and Ecosystems of thè Geological Past. Nauka,

Moscow: 7-21. (In Russian).

Fedonkin M. A., 1994a - Vendian body fossils and trace fossils.

In: Bengston S. (ed.). Early Life on Earth (Nobel Sympos¬

ium 84). Columbia University Press.

Fedonkin M. A., 1994b - Geobiological trends and eventts in

thè Precambrian biosphere. In: Walliser O. H. (ed.). Global

Biological Events in Earth History (Final volume of IGCP

Project 216) (in press).

Gebelin C. D., 1976 - The effect of thè physical, Chemical and

biological evolution of thè Earth. In: Walter M. R. (ed.).

Stromatolites: Developments in Sedimentology. Elsevier,

Amsterdam, 20: 499-516.

Gehling J. G., 1991 - The case for Ediacaran roots to thè meta-

zoan tree. Memoirs of thè Geological Society of India, 20:

181-224.

Glaessner M. F., 1984 - The Dawn of Animai Life. A Biohistori-

cal Study. Cambridge University Press, Cambridge: 224 pp.

Glaessner M. F. and Daily B., 1959 - The geology and thè late

Precambrian Fauna of thè Ediacara fossil reserve. Records of

thè South Australian Museum, 13 (3): 369-401.

Glaessner M. F. and Wade M., 1966 - The late Precambrian

fossils from Ediacara, South Australia. Paleontology, 9 (4):

599-628.

Golubic S. and Hofmann H. J., 1976 - Comparison of modera

and mid-Precambrian Entophysalidaceaea (Cyanophyta) in

stromatolite algal mats: celi division and degradation. Jour¬

nal of Paleontology 50: 1074-1082.

Grotzinger J. P., 1990 - Geochemical model for Proterozoic

stromatolite decline. American Journal of Science, 290-A:

80-103.

Grunbaum A., 1969 - Philosophical Problems of Space and Time.

Progress, Moscow: 590 pp. (In Russian).

Gurich G., 1929 - Dis bisland altesten Spuren von Organisme in

Sudafrika. International Geological Congress, Pretoria, 15:

670-680.

Hahn J., 1982 - Geochemical fossils of a possibly archaeobacte-

rial origin in ancient sediments. Zbl. Bakt. Hyg. J. Abt. Orig.,

C3: 40-52.

Hayes J. M., Des Marais D. J., Lambert I. B., Strauss H. and

Summons R., 1992a - Proterozoic biogeochemistry. In:

Schopf J. W. and Klein C. (eds.). The Proterozoic Biosphere.

A. Multidisciplinary Study. Cambridge University Press,

Cambridge: 81-134.

Hayes J. M., Lambert I. B. and Strauss H., 1992 b. - The sul-

phur isotopie record. Cambridge University Press, Cambrid¬

ge: 129-132.

Hoering T. C., - 1987 - A search for molecular fossils in thè ke-

rogen of thè Precambrian sedimentary rocks. Precambrian

Research, 34: 247-267.

Hofmann H. J., 1971 - Precambrian Fossils, Pseudofossils and

Problematica in Canada. Bulletin Geological Survey of Cana¬

da, 189: 146 pp.

Hofmann H. J., 1972 - Precambrian remains in Canada: fossils,

dubiofossils, and pseudofossils. International Geological

Congress, 24th Session, Montreal. Proceedings, Section 1:

20-30.

Hofmann H. J., 1992 - Proterozoic carbonaceous films. In:

Schopf J. W. and Klein C. (eds.). The Proterozoic Biosphere.

A Multidisciplinary Study. Cambridge University Press., New

York: 349-357.

Holland H. D. 1984 - The Chemical Evolution of thè Atmosphe-

re and Ocean. Princeton University Press, Princeton: 582 pp.

Holland H. D., 1992 - Major aspeets of atmospheric evolution

during thè Precambrian. International Geological Congress,

29th Session, Kyoto. Abstracts, 1: 170 pp.

Kasting J. F. and Ackerman T. P., 1986 - Climatic consequences

of very high C02 level in earth’s early atmosphere. Science,

234: 1383-1385.

Kirschvink J. L., 1982 - Magnetite biomineralization and thè

evolution of thè eucaryotic celi. International Geological

Congress, 29th Session, Kioto. Abstracts, 2: 340 pp.

Knoll A. H., 1985 a - Exceptional preservation of photosynthetic

organisms in silicifìed carbonates and silicifìed peats. Philo¬

sophical Transactions of thè Royal Society of London, B 311:

111-122.

Knoll A. H., 1985 b - A paleobiological perspective on sabkhas.

In: Friedman G. M. and Krumbein W. E. (eds.). Hypersaline

Ecosystems. Springer, Berlin: 407-427.

Knoll A. H. and Bauld J., 1989 - The evolution of ecological tol-

lerance in procaryotes. Transaction of thè Royal Society of

Edinburgh. Earth Sciences, 80: 209-223.

Krylov I. N., 1963 - Columnar Branchiong Stromatolines from

Riphean Deposits of South Urals and Their Significance for

thè Stratigraphy of Upper Precambrian. Transactions of thè

Geological Institute. USSR Academy of Sciences. Nauka,

Moscow, 69 170 pp. (In Russian).

Krylov I. N., 1975 - Stromatolites of thè Riphean and Phanero-

zoic of thè USSR. Nauka, Moscow: 243 pp. (In Russian).

Krylov I. N., 1988 - The first ecological catasprophe has already

happened. Znaniye-Sila, 2: 44-47. (In Russian).

Krylov I. N. and Tikhomirova N. S., 1988 - On thè formation of

silicifìed microfossils. Paleontologicheskii Zhurnal, 3: 3-9. (In

Russian).

Lovelock J. E., 1979 - Gaia: A New Look at Life on Earth. Oxford

University Press, New York: 157 pp.

Lowenstan H. A. and Weiner S., 1989 - On Biomineralization.

Oxford University Press, New York: 324 pp.

Maslov V. P. 1960 - Stromatolites. Transactions of thè Geologi¬

cal Institute. USSR Academy of Sciences. Nauka, Moscow,

4L (In Russian).

Monster J., Appel P.W. U., Thode H.G. and Bridgewater D.,

1979 - Sulfur isotope studies on early Archean sedi¬

ments from Isua, West Greenland. Implications for thè

antiquity of bacterial sulfate reduction. Geochimica Acta,

43: 405-413.

Monty C. L.V., 1974 - Precambrian background and Phanerozoic

history of stromatolitic communities, an overview. Annales

del la Societe Geologique de Belgique, 96: 585-624.

Muir M. D., 1978 - Microenvironments of some modera and

fossil iron- and manganese-oxidising bacteria. In: Krum¬

bein W. E. (ed.). Environmental Biogeochemistry and Geo-

microbiology. Ann Arbor Scientific Pubi., Ann Arbor, MI:

937-944.

Ourisson G., 1990 - The generai role of terpenes and their global

significance. Pure and applied Chemistry, 60 1401-1404.

Pierson B. K., 1988 - Ecology and physiological characteristics of

modera microbial mats: perspectives for interpretations of

Proterozoic benthic communities. In: The Proterozoic Bio¬

sphere: a multidisciplinary study. A Symposium. University

of California, Los Angeles: 25-26.

Riding R. and Voronova L., 1982 - Calcified cyanobacteria and

thè Precambrian-Cambrian transition. Naturwissenschaften,

69: 498-499.

Riding R. and Voronova L., 1984 - Assemblages of calcareous

algae near thè Precambrian/Cambrian boundary in Siberia

and Mongolia. Geological Magazine, 121: 205-210.

Rothschild L. D. and Mancinelli R. L., 1990 - Model of carbon

fixation in microbial mats from 3,500 Myr ago to thè present.

Nature, 345 (6277): 710-712.

Schopf J. W., 1992 a - The oldest fossils and what they mean. In:

Schopf J. W. (ed.). Major Events in thè History of Life. Jones

and Bartlett Publishers Ine., Boston: 29-61.

Schopf J. W., 1992 b - Petterns of Proterozoic microfossil diversi-

ty: an initial tentative analysis. In: Schopf J. W. and Klein C.

(eds). The Proterozoic Biosphere. A Multidisciplinary study.

Cambridge University Press, new York: 529-552.

Schopf J. W., 1992 c - Proterozoic procaryotes: affìnities, geo¬

logie distribution, and evolutionary trends. Cambridge Uni¬

versity Press, New York: 195-218.

Schopf J. W. and Clein C. (eds.), 1992 - The Proterozoic Bio¬

sphere. A Multidisciplinary Study. Cambridge University

Press, New York: 1348 pp.

Seilacher A., 1989 - Vendozoa: organismic construction in thè

Proterozoic biosphere. Lethaia, 22: 229-239.

Seilacher A., 1990 - Precambrian evolutionary experi-

ments: Vendozoa and Psammocorallia. In: Alberch P. and

Dover G. A. (eds.). The Reference Points in Evolution. Fun-

dacion Juan March., serie Universitaria, 225: 48-53.

Semikhatov M. A. and Raaben M. E., 1993 - Dynamics of syste-

matic diversity of Riphean and Vendian stromatolites of

northern Eurasia. Stratigraphy. Geological Correlation, 1

(82): 3-12. (In Russian).

Sokolov B. S. and Fedonkin M. A., 1988 - Early stages of life

development on Earth. In: Menner V. V. and Makridin V. P.

(eds.). Modera Paleontology. Nedra, Moscow, 2: 118-141. (In

Russian).

Sprigg R. C., 1947 - Early Cambrian (?) jellyfishes from thè

Flinders Ranges, South Australia. Transactions of thè Royal

Society of South Australia, 71: 212-234.

48

MIKHAIL A. FEDONKIN

Sprigg R. C., 1949 - Early Cambrian «jellyfishes» of Ediacara,

south Australia, and Mount John, Kimberley Distict, wes¬

tern Australia. Transactions of thè Royal Society of South

Australia, 73: 72-99.

Summons R. E. and Walter M. R., 1980 - Molecular fossils of

procaryotes and protists from Proterozoic sediments. Ameri¬

can Journal of Science, 290-A: 212-244.

Thompson D. W., 1942 - On Growth and Form. Cambridge Uni¬

versity Press, Cambridge: 1116 pp.

Vernadski V. I., 1926 - Biosphere. Leningrad. 146 pp. (In Rus-

sian).

Walter M. R. (ed.), 1976 - Stromatolites. developments in Sedi-

mentology. Elsevier, Amsterdam, 20: 790 pp.

Walter M. R., 1992 - Stratigraphic distribution of stramatolites

and alliend structures. In: Schopf J. W. and Klein C. (eds.).

The Proterozoic Biosphere. A Multidisciplinary Approach.

Cambridge University Press, New York: 507-509.

Walter M. R. and Hayes G. R., 1985 - Links between thè rise of

thè metazoa and thè decine of stromatolites. Precambrian

Research, 29: 149-174.

Zavarzin G. A., 1984 - Bacteria and thè Composition of thè

Atmosphere. Naika, Moscow: 199 pp. (In Russian).

I

Mikhail A. Fedonkin: Paleontological Institute, Russian Academy of Sciences, Profsoyuznaya ul. 123, Moscow 117647 RUSSIA

Systematic Biology as an Historical Science

Memorie della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano

Volume XXVII - Fascicolo I - 1996

Michael T. Ghiselin

Charles Darwin, Fritz Miiller, Anton Dohm, and thè origin

of evolutionary physiological anatomy

Abstract - Darwin brought a truly historical perspective into evolutionary biology that differed fundamentally from

formalistic and orthogeneticist notions of change. His approach to historical reconstruction was strongly influenced by his

geological research. Scenarios in his monograph on barnacles illustrate his physiological approach, with functional conti-

nuity playing a major role. His ideas on thè relationship between ontogeny and phylogeny were later taken up and applied

to other crustaceans by Fritz Miiller before Haeckel developed thè same theme. Anton Dohrn, who also worked on crusta-

ceans, owed much to Darwin for his physiological approach to phylogenetics, especially thè principle of Funktionswechsel

or succession offunction. The tradition continued with thè Russian school of evolutionary morphologists, notably Sewert-

zoff and Schmalhausen.

Among thè many myths in thè history of evolu¬

tionary biology is that nothing of great importance

happened to comparative anatomy when Darwin

carne along. Like a lot of myths, it has a certain foun-

dation in fact. Comparative anatomists could indeed

get away with proceeding just as they always had,

and some of them did. For many, thè changes were

superficial — perhaps little more than acknowledging

that taxonomic groups have common ancestors. For

some, thè very denial that there was a Darwinian re¬

volution in comparative anatomy, or even that such a

revolution is possible, has been one way of opposing

such changes. For others, it has been a means of

stressing thè very novelty of Darwinian thinking, and

thè conservativeness of thè opposition.

Here I shall argue that something of great signifì-

cance really did happen to comparative anatomy as a

result of Darwin’s work. Darwin recognized that it

had, and he acted upon it. So too did some of his

supporters, and thè consequence were momentous.

If their accomplishments go largely unacknowled-

ged, it is partly because they seem all too obvious,

and partly because they have been forgotten, if not

outright suppressed.

The very refusai to recognize important differen-

ces between pre-Darwinian and Darwinian attitudes

toward nature would seem to reflect a persistence of

those very attitudes that Darwin called into question.

To Darwin’s predecessors, change was something to

be denied, or at least minimized. If not downright

illusory, it was superficial and not very important. To

Darwin, on thè contrary, change was not just import¬

ant, it was thè fundamental reality. Naturai selection

produced things that are novelties in a deeply meta-

physical sense, one that was lacking in earlier

thought.

Let me contrast thè old way of thinking with thè

new, albeit with thè proviso that I have to simplify a

bit for thè sake of clarity (see Ghiselin, 1980). Pre-

Darwinian biologists were perfectly aware that chan¬

ge of a sort occurs in thè ontogeny of individuai or-

ganisms. The term «evolution» originally meant

embryological development, and thè «development

hypothesis» was often used for thè views of Lamarck

and his followers. Efforts to deal with evolution in

our modera sense were largely based upon analogies

with evolution in thè older, embryological sense.

There were two basic ways of thinking about an on¬

togeny, namely preformation and epigenesis. In ei-

ther case, things went from one particular condition

to another particular condition — from A to B — un-

less, perhaps, something interfered with thè normal

state of affairs. Change was not «reai» insofar as eve-

rything was pre-ordained. For preformationists, on¬

togeny was a sort of «unfolding» or a change from a

condition of potentiality to one of actuality. For epi-

geneticsts, ontogeny was thè result of thè action of

supposed laws of nature, and was often analogized with

thè growth of a crystal. Here, change would not be reai,

insofar as thè laws of nature are eternai; a crystal of a

given kind will precipitate out of solution whenever

thè necessary and sufficient conditions are met.

When such notions are translated into an evolu¬

tionary context, one gets somewhat different ver-

sions of what is often called «orthogenesis.» In thè

preformationist version, thè changes that might be

called «evolutionary» were attributed to thè will of

an omnipotent and omniscient Being, who foresaw

and indeed pre-ordained everything. In thè epigene-

ticist version, that same Being ordained thè laws of

nature, with much thè same generai effect. As one

might expect, such thinking was both vague and flex-

ible, so that one might invoke a wide range of posi-

tions with respect to what might cause thè changes in

question. Often unknown «laws» or mysterious «for-

ces» or «tendencies» were invoked.

Once we realized that such notions of causality

were presupposed, it is most misleading to label such

pre-Darwinian figures as Buffon, Lamarck, or Owen

«evolutionists» in our modera sense. It is also easy

to see why Darwin, like many other scientists, con-

sidered such quasi-evolutionary notions unscientific.

Miracles and occult forces were not amenable to

scientifìc investigation. Darwin, to be sure, believed

that ontogeny plays an important causai role in evo¬

lution. But like us moderns he believed that whate-

ver it is that causes ontogeny also evolves. And like

us moderns he believed that evolution is governed

50

MICHAEL T. GHISELIN

by laws of nature. Much of his research was aimed at

discovering such laws.

Darwin was an «evolutionary physiological ana-

tomist» in thè sense that he explained life as thè

consequence of thè vital activities of reai, concrete

organisms, through time. The physiological aspect

of Darwin’s evolutionary biology is not always ap-

preciated. His classic work on plant movements is

highly esteemed by physiologists. However, thè evo¬

lutionary aspect of this work is only apparent when

one considers his little book on The Movement and

Habits of Climbing Plants (Darwin, 1865). Here he

provides scenarios for changes in both behavior and

anatomy. I mention this work primarily to make thè

generai point that Darwin was anything but a «for¬

mai morphologist» or someone who believed that

studies of form should be divorced from studies of

function. Indeed thè term «functional morphology»

is an oxymoron if thè word «morphology» is used in

its strict and originai sense.

Darwin was also a geologist, and this further dis-

tanced him from formai, and a fortiori from idealis-

tic, morphology. During his trip around thè world

Darwin carried out extensive geological research

under thè influence of Charles Lyell’s Principles of

Geology. This research was of cruciai importance, for

it gave Darwin a great deal of first-hand experience

in thè kind of historical thinking that he would later

apply to biology. Although Lyell did not himself be-

lieve in evolution, thè kind of thinking that he advo-

cated only had to be carried a little further to trans-

form biology into thè sort of historical Science that

geology had already become. Lyell had a «steady

state» view that limited thè amount of change, and

Darwin had to reject that. But thè notion that change

is graduai could easily be accommodated in a biolo-

gical context. More fundamental was thè point that

thè laws of nature, which do not change, can be used

to reconstruct past events. If one knows a law of na¬

ture, then one knows what can and cannot happen at

any time whatsoever. Consequently a geologist can

ask what possible events might explain thè present

configuration of thè earth, and rule out some of thè

possibilities on thè grounds that laws of nature rule

them out. Or to put it more loosely, thè narrative

theories gained plausibility when they were shown to

exemplify broad generalizations. Darwin’s coral reef

theory is clearly based upon «global» considerations,

much as is modera piate tectonics. How much these

more basic generalizations are laws and how much

they are particulars is a question that deserves fur¬

ther consideration.

Another important benefit that Darwin gained

from studying geology was thè habit of conceptualiz-

ing problems in terms of concrete objects and reai

events. Even though geologists’ diagrams can be

schematic, there is rarely any doubt that they are dia¬

grams of reai rocks and strata, not diagrams of «rock»

in thè abstract. Systematists were much more apt to

treat groups of objects as abstractions, and both their

language and their diagrams had a strongly metapho-

rical character. So although some of Darwin’s prede-

cessors drew «tree-like» diagrams, these rarely if ever

had thè connotations of a nexus of reai parents and

offspring. They were merely a way of expressing thè

notion of similarity and difference. Likewise there

was a profound difference between thè «archetypes»

ofidealistic morphologists like Oven, which were ab¬

stract schemes, and thè so-called «archetypes» of

Darwin, which were reai organisms that must have

metabolized and done all those other things that or¬

ganisms do.

Darwin’s work on Crustacea provides excellent

materials for studying his phylogenetic methodo-

logy. Although it was published before Darwin pu-

blicly announced his evolutionary point of view, there

is no question that his Monograph on thè Sub-Class

Cirripedia (Darwin, 1851, 1854) was a work on evolu¬

tionary systematics. We know this from his corres-

pondence, as well as from his commentary in The

Origin of Species and elsewhere. Furthermore, and

this is very important, his contemporaries, including

Crustacean systematists who were among his most

enthusiastic supporters, read thè monograph as

straight-forward phylogenetics. They applied his me-

thods to similar material. Because thè monograph

has been foundational for all subsequent work on

thè group, students of barnacles have provided some

excellent commentary. The latest analysis by New-

man (1993) is an outstanding example, and one to

which thè present discussion owes a great deal. (See

also Ghiselin, 1969; Burkhardt and Smith, 1988).

Darwin of course was fully aware of thè fact that

his predecessors had been able to create «naturai Sys¬

tems» of classification with hierarchies of groups wi-

thin groups that shared diagnostic characters. The

classification in his barnacle monograph bears out

thè position he took in thè Origin that classification

should be strictly genealogical, though he allowed

for «paraphyletic groups» (ones that do not include

all of thè descendants of thè common ancestor) to

express thè «amount of difference» (Ghiselin and

Jaffe, 1973). In later publications he took a stronger

position in favor of strict monophyly (Ghiselin,

1985). When one thinks in terms of taxonomic

groups, strict monophyly allows one to avoid mistak-

ing a group that has undergone much divergence for

one that branched off early. This same mistake, ho¬

wever, can be avoided by using «tree thinking» ra-

ther than «group thinking» (O’Hara, 1988). If one

thinks in terms of trees, one also thinks more clearly

about what characters are really important, including

thè ones that are «derived» or as cladists say «apo-

morphic». Darwin did not discuss such matters ex-

plicitly, and he seems to have taken a rather «com-

mon-sensical» approach, much as he did in geology.

His basic classification has not been much revised as

more has become known about thè group and as ge¬

nealogical classification has become increasingly po-

pular within systematics in generai.

It is of considerable interest that for Darwin thè

diagnostic feature of thè Cirripedia was attachment

of thè cyprid larva by a particular kind of highly-mo-

dified «antenna», definitely a derived condition. He

justified this character on thè basis of its «high phy¬

siological importance» and there being no strict pre-

cedent for it in other groups. It would seem that for

cirripedes «high physiological importance» means a

kind of technological breakthrough that allows thè

further evolution of thè group (a key innovation),

and for something that lives as they do, such an

adaptation is not likely to be secondarily lost.

Whether thè complexity of this attachment organs

was seen as a criterion for considering it most unlike-

ly to have evolved more than once is something I

cannot answer at thè present time. However this ex-

CHARLES DARWIN, FRITZ MULLER, ANTON DOHRN, AND THE ORIGIN OF EVOLUTIONARY PHYSIOLOGICAL ANATOMY

51

ampie suffices to refute thè notion that Darwin belie-

ved that classification should be based only upon

characters of trifling physiological significance. He

did think that his theory could explain why some

characters with no obvious utility were often of high

diagnostic value, but that is a very different issue.

Darwin’s scenario for thè origin of cirripides invo-

ked as a common ancestor a rather advanced crusta-

cean that fed with its feet then became attached by

its antennae and subsequently underwent much mo-

dification. Given that thè animals were very different

from other crustaceans, one might take this to mean

that they were an early branch of thè Crustacea. But

Darwin made no such mistake, and this negative evi-

dence is significant. For him thè question of relation-

ship was not a matter of similarity, but of whether

there might have been intermediate forms. Such in-

termediates also had to be physiologically viable or-

ganisms, not just morphological intermediates. In

his debate whith Étienne Geoffroy Saint-Hilaire, Cu-

vier invoked thè implausibility of functionally viable

intermediates as a means of ruling out thè derivation

of one kind of organism from another, and his argu-

ments were perfectly legitimate in that context.

However, Darwin and his followers turned thè argu-

ment on its head, and used thè argument from

physiological continuity as a means of phyloge-

netic inference. One goes back to thè most recent

plausible common ancestor that would not be

excluded by such considerations. He believed that

he had found what we would cali thè «sister group»

of cirripides well within thè Crustacean phylogenetic

tree. Thus he seems to have reasoned by putting

things together on thè basis of shared characters,

rather than by separating them on thè basis of diffe-

rences.

In considering Darwin’s «model» for thè origin of

thè Cirripedia, one might wonder to what extent thè

scenarios are merely an afterthought to tree-like dia-

grams established upon some other basis. Or are

they are something constitutive, in thè sense of pro-

viding support for thè trees themselves? I believe

that Darwin would have answered that they are in-

deed constitutive. The ancestral cirripede itself may

not be a good example of this. However, thè use of

functional criteria for establishing homologies which

are in turn evidence for relationships, is commonpla-

ce in Darwin’s work. So far as he could, he tried to

derive new structures from pre-existing ones, per-

haps with a change in function. We face a problem

here. Darwin gives two examples of thè origin of

such features in cirripedes, and they both turn out to

be mistaken: thè cement glands and probably thè

ovigerous frena (Walker, 1983). There are plenty of

good examples, however, and such «plausibility ar-

guments» are by no means uncommon in phyloge¬

netic reasoning. I will come back to them later when

I discuss thè contribution of Dohrn.

The principle of functional continuity can be deri-

ved from thè theory of naturai selection, but it is also

consistent with any theory that entails thè viability of

hypothesized organisms in a sequence of reai ances-

tors and descendants. Naturai selection, however,

specifìes conditions under which certain kinds of

changes do and do not occour, and therefore can be

invoked to rule out certain kinds of changes that

otherwise might seem possible. Naturai selection

cannot adapt a population to selection pressures that

it has not yet encountered, or, to put it in more liter-

ary language, it has no foresight. The most clear-cut

example is vestigial organs, which have to be inter-

preted as parts that are in thè process of being lost,

rather than gained. Advocates of orthogenesis, espe-

cially preformationist versions, have not been thus

constrained.

Darwin discussed thè importance of vestigial

structures for phylogenetic research in thè Origin of

Species. He had extensive experience with them in

his work on barnacles. Such structures were particu-

larly evident in thè dwarf males that he found asso-

ciated with hermaphrodites and fermales in certain

lepadomorph barnacles. What use he made of vesti¬

gial parts in reconstructing thè evolutionary history

of thè group is not always clear from thè text, and

some of thè examples may seem a bit obscure. He

thought he saw vestiges of missing segments in thè

cypris larva. In Chelonibia, a pair of vestigial sutures

convinced him that thè «rostrum» of higher balani-

nes had been formed by thè fusion of thè true ros¬

trum with thè adjacent plates.

A more straight-forward example of functional

reasoning is seen in his decision that thè males in cir¬

ripedes are hermaphrodites in which thè female parts

have been lost, and which have subsequently been

reduced. It makes a lot more sense for a tiny, and

often gutless animai with appendages that are redu¬

ced or missing, single gonads and no intromittent

organ to be thè endpoint of regressive evolution, ra¬

ther than thè beginnings of a more complicated crea¬

ture. Furthermore, Darwin believed, as we do, that

thè males in barnacles had been produced by a me-

chanism called «progenesis» involving loss of later

developmental stages and early sexual maturation.

This brings us to a consideration of Darwin’s

views on thè relationship between embryology and

evolution. In addressing this topic it should be stated

at thè outset that there are serious problems with thè

literature on thè relationship between ontogeny and

phylogeny. Much of it has been written by persons

who have little if any sympaty with phylogenetics as

a topic for scientific research. This is particularly thè

case with advocates of «experimental» approaches.

The problem is exacerbated by factional disputes

among systematists. A great deal of mythology has

been built up, and therefore it is essential that one go

back and consult thè originai documents, especially

those that are neglected in thè secondary literature.

In his Autobiography (Barlow, 1959:125) Darwin

expresses dismay at how little attention was given to

what he said about thè relationship between ontoge¬

ny and phylogeny in thè Origin of Species, where, he

believed (and I think rightly), he had provided thè

basic solution to such problems. He goes on to say

that «Within late years several reviewers have given

thè whole credit of thè idea to Fritz Miiller and

Hàckel, who undoubtedly have worked it out much

more fully, and in some respects more correctly than

I did.» Subsequently Miiller has been largely for-

gotten. But Miiller gave Darwin full credit, and thè

importance of Miiller’s contribution was widely re-

cognized by his contemporaries.

During thè 1830s and 1840s Darwin familiarized

himself with thè views of his predecessors as he de-

veloped his own. He was well aware of what those

views were, although he often relied upon secondary

sources. He could not accept their explanations for

52

MICHAEL T. GHISELIN

thè relationships between embryology and classifica-

tion, which contradicted not only his own theory, but

his very idea of what constitutes a legitimate scientif-

ic theory in generai. Both thè preformationist and

thè epigeneticist versions of «recapitulation» had to

be ruled out. However, given that developmental

processes evolve as a consequence of selection, he

could explain thè observed phenomena and there-

fore use them as evidence in favor of his theory. In

thè context of phylogenetics this meant that thè de-

velopment of an organism might contain valuable

clues as to its ancestry.

According to Darwin’s theory, variations arise

fortuitously (not at random in thè sense that one

variation is as probable as another) at any stage in

development. If passed on to thè next generation,

they tend to appear at thè same stage as they did in

thè parent. Variations accumulate as a consequence

of selection, thè nature of which is contingent upon

thè conditions of existence. So both 1) thè time in

ontogeny at which a variant appears and 2) thè time

in ontogeny at which its presence affects fitness are

capable of affecting how thè entire fife cycle will

evolve. Early variants or early selection could produ¬

ce early divergence, perhaps conpled with late diver¬

gere as well. But if selection in different lineages

was on late variants or late in thè fife cycle, or both,

thè young stages would remain unaltered. Which of

these happened in any particular case would be a

matter of (contingent) historical fact, and would

have to be worked out by historical biologists. If laws

were to be used in such reconstruction, they had to

be thè laws that govern variation, selection, and

other processes. Darwin believed that an under-

standing of developmental mechanisms would help.

But there was no way in which he could simply con-

join a description of an organismi ontogeny with a

statement of relevant laws and infer its history.

One might question whether thè above recons¬

truction of Darwin’s views is correct. It is justified by

thè generai pattern of his procedures as well as by his

explicit statements. In thè Origin of Species Darwin

gives a succinct account of his views, one that was

perhaps too brief for many readers to have under-

stood it (Darwin, 1859:439-450). His detailed exposi-

tion of his views on thè relationship between em¬

bryology and evolution is explained in The Variation

of Animals and Plants under Domestication (Darwin,

1868), a work that is rarely even mentioned in this

context. Indeed, because it is wrongly considered a

book on heredity, and one that contains a theory that

is no longer credible, it is virtually never read by an-

ybody (see Ghiselin, 1975). Darwin derived his views

on developmental physiology from his readings of

works on plant and animai breeding, teratology and

related subjects, through conversation and corres-

pondence with many informants, and from his own

empirical research. In thè book on Variation he gives

examples of changes occuring at various stages in thè

fife cycle. It is important to stress that they are not li-

mited to thè end of ontogeny, as strict recapitulatio-

nism would have it.

In thè Monograph on thè Sub-Class Cirripedia, w e

fìnd clear applications of Darwin’s embryological

principles to phylogenetic analysis. Of course he

used these principles together with all thè other evi¬

dence that was available to him. Dana and Milne Ed-

wards had divided most of thè Crustacea into three

groups which Darwin evaluated as thè possible clo-

sest relatives of thè Cirripedia: Entomostraca,

Edriopthalmia, and Podopthalmia. He opted

(1854:13) for thè last of these, thè «stalk-eyed» crusta-

ceans, on thè basis of various characters, including

details of thè structure of thè carapace and its deriva-

tes. Within thè Podopthalmia he noted that there

was an «aberrant group of low organisation»

(1854:18) which combined a mixture of entomostra-

can and podopthalmian traits and had more in com¬

mon with thè Cirripedia than any other group. The

group included Phyllosoma , which turned out to be

larvae of palinurids (spiny lobsters) and Amphion.

This group he said (1854:19) «leads into thè Stomo-

poda», which included Lucifer, Darwin’s model for a

cirripede ancestor. Lucifer is a pelagic animai, now

placed in thè order Decapoda and suborder Dendro-

branchiata (=Penaeidoidea), and includes Amphion.

How dose a relationship he invoked is not clear from

Darwin’s text. However, his views on thè homolo-

gies of limbs provide a good reason for relating thè

Cirripedia to an early offshoot of thè malacostran li-

neage. Namely, he thought that thè last cephalic and

fìrst thoracic segments in cirripedes had been redu-

ced (1854:111), rather than thè last two thoracic seg¬

ments as was thè opinion of Dana (Darwin, 1854:22)

and later authors. He thought he had some evidence

for this in thè reduced condition of these limbs in

Phyllosoma and allied forms (1854:18); and this view

seems to have been justified by reference to thè work

of Henri Milne Edwards (1834-40) whose «Stomapo-

da» included what are now called «Stomatopoda»

(Hoplocarida», and mysids, as well as Lucifer and

some larvai forms.

The figure of Lucifer that appears in Darwin’s mo¬

nograph (1851:28) was copied from Milne Edwards

(PI. 28). Below it Darwin presents a drawing of «a

mature Lepas, with thè antennae and eyes, which are

actually present in thè larva, retained and supposed

to have gone on growing». The claim of Richards

(1992) that this is a larvai crustacean is an egregious

blunder, and thè work is seriously flawed in other

respects as well (Ghiselin, 1992). For Darwin, thè

cirripedes were a group of early malacostracans that

became sessile fìlter-feeders and then underwent

considerable reorganization and subsequent adap-

tive radiation. Both progressive and regressive chan¬

ges were involved, and thè scenario presented was

anything but orthogenetic.

Among thè «regressive» changes that Darwin in¬

voked were thè regression of parts among parasitic

forms. When Darwin invoked thè «arrest» of deve¬

lopment in simple animals he really meant that so-

mething previously present had ceased to develop;

this is fundamentally different than thè claims by

some of his predecessors that simple animals have

not undergone thè sort of ontogeny that thè more

complex ones might. So when he refers to thè

«Apoda» as «larvai» he is talking about progenetic

animals. In his scenario for thè evolution of dwarf

males from hermaphrodites, he treats thè reduction

of thè males as a case of progenesis, which is a modi-

fìcation of thè developmental mechanism. He justi-

fies thè invocation of progenesis by reference to thè

histological appearance of thè tissues of thè males:

they look like those of larvae, not adults. So although

thè reduction of thè males was supported by conven-

tional synapomorphies, strictly physiological criteria

CHARLES DARWIN, FRITZ MULLER, ANTON DOHRN, AND THE ORIGIN OF EVOLUTIONARY PHYSIOLOGICAL ANATOMY

53

were also invoked. Further processual evidence for

thè reduction of thè males was provided by vestigiali-

ty of parts, and by thè generai plausibility of adaptive

change in thè mode of reproduction.

If we want to find evidence that Darwin produced

some kind of change in thè lives of comparative ana-

tomists, we ought to examine thè work of those who

were most likely to understand his views, those who

not only accepted his theory, but embraced it with

unqualified enthusiasm. A particularly good exam-

ple is Fritz Muller (1822-1897). His discovery of

Mullerian mimicry is good evidence that, unlike

most nineteenth century «evolutionists», he under-

stood naturai selection very well. If anything, his po-

litics and his religion disposed him to favor naturai

selection and its implications, for left Germany upon

religious grounds in 1852, and spent his remaining

years in Brazil. He did a great deal of research on thè

anatomy, embryology, and phylogenetics of various

marine organisms, especially crustaceans. He pre-

sented his work on crustaceans as a kind of test of

Darwin’s theory in his book Fùr Darwin (Muller,

1864), which pleased Darwin so much that he had it

translated into English as Facts and Arguments for

Darwin (Muller, 1869).

Muller provides various arguments for Darwin, in-

cluding evidence for sexual selection in thè form of

«high-low» dimorphism among Tanaidacea (Mala-

costraca: Peracarida). He shows clear evidence of

having given a great deal of thought to what now is

called «character analysis» in a cladistic context. He

shows by (p. 7) a pair of what can only be called «cla-

dograms» two lines of evidence, on thè one hand a

large, asymmetrical chela that might be a good syn-

apomorphy for several species, and, on thè other

hand, thè absence of a second branch to thè fìrst an-

tennae that might be a convergent loss. But this dis-

cussion is rather fragmentary and does not explicity

address such issue as plesiomorphy and thè use of

outgroups.

Muller presents a most impressive effort to apply

Darwin’s ideas about thè relationship between onto-

geny and phylogeny to thè Crustacea. He recognized

two basic kinds of larvae, thè nauplius and thè zoea,

which may exist in thè same life cycle. In thè most

primitive crustaceans then known, thè Phyllopoda

(as then understood, roughly equivalent to our Bran-

chiopoda), a nauplius stage is followed by an adult

stage which is essentially equivalent to a zoea, but

lacks thè modifications that occur in both thè zoea

and thè adult of higher crustaceans (so that there are

a long series of relatively undifferentiated appenda-

ges). In higher crustaceans thè zoea has its characte-

ristic features and thè adult is more modifìed in

structure. Miiller (1869) had established that a group

of highly degenerate internai parasites of crusta¬

ceans, thè Rhizocephala, are closely related to thè

Cirripedia, and had done so mainly on thè basis of

their characteristic larvae, thè oldest of which have

some features suggestive of a zoea. He proposed that

thè Rhizocephala are what we now would cali thè sis-

ter group of thè true barnacles (Thoracica), as is ge-

nerally maintained today. Barnacles have nauplii and

a «cypris» or cyprid larva, so-called because it resem-

bles an adult ostracod. Darwin called thè cypris a «lo¬

comotive pupa» and thè term expresses its function

as a specialized, non-feeeding stage that settles and

undergoes metamorphosis into thè juvenile. Miiller

(1864) dismissed thè resemblance to ostracods as

convergent. According to Newman (1983) thè traces

of a zoea in thè Maxillopoda (Copepoda, Cirripedia,

Ascothoracica, Branchiura, Mystacocarida, and Os-

tracoda) are reai, and thè Maxillopoda are a clade re¬

lated to thè «urmalacostracans» that have undergone

a loss of segments due to progenesis.

Fritz Miiller clearly and emphatically rejected thè

efforts of Johannes Miiller, Louis Agassiz, and, wi-

thout naming him, Karl Ernst von Baer, to explain

thè parallels between thè taxonomic hierarchy and

thè sequence of development in crustaceans in terms

of what he dismissed, explicity, as scholastic philoso-

phy. Rather, he adopted and developed thè interpre-

tation that Darwin had presented in thè Origin of Spe¬

cies. Observing that variations might occur early or

late in ontogeny, he explained that there might be

very different results. An animai might deviate early

in ontogeny; in that case it would retain thè originai

condition only for a short period. Or it might add

new stages at thè end of ontogeny; if so ontogeny

would pass through thè series that mirror thè history

of thè species. The important point here is that «ter¬

minal addition» is thè one condition under which re-

capitulation applies in a straight-forward manner. He

also concluded that thè phylogenetic evidence may

get obliterated when development becomes direct,

or it may get falsified as a result of naturai selection

undergone by free-living larvae. In order to infer

what thè actual history had been, one had to apply

some principles and rules. Arthropods with more

pronounced metamorphosis had probably deviated

more than others from thè ancestral condition, as

had those with greater difference in way of life — thè

two, of course being strongly correlated.

Muller goes on to interpret thè development of thè

Malacostraca in thè light of this theory. He proposed

that thè zoea larva gives thè best picture of thè ances-

try of thè group. He thought that thè nauplius larva

had been obliterated in these higher Crustacea, al-

though he found traces of it in thè relatively primi¬

tive Mysis. Spines on thè zoea he interpreted as de-

fensive adaptations that had arisen in thè larva. Gra¬

duai differentiation of segments toward thè posterior

was treated as thè ancestral condition, whereas si-

multaneous differentiation of these was thè result of

a condensation and simplification of development.

Muller does not provide anything like an «algo-

rithm» for dealing with such problems. A great deal

of ingenuity would seem to be involved. However it

is clear that he recognized from thè outset that thè

history of thè lineage cannot be read off in a straight-

forward manner from ontogenetic data.

It is easy to see, however, that people might read

thè works of Darwin and Muller and ignore or forget

thè difficulties. Or they might get their information

from other sources such as Ernst Haeckel (1834-

1919). Even if people read such technical works as thè

Generelle Morphologie (Haeckel 1866) his popular

writings obviously oversimplifìed matters. Haeckel

was also a very effective teacher, and his students na-

turally learned Haeckel’s version of what was called

Darwinism. It emphasized morphology and recapitu-

lation rather than thè kind of functional thinking that

was so characteristic of thè work of Darwin himself.

One such student of Haeckel was Anton Dohrn

(1840-1909). He began his career as an entomologist,

then, as a result of reading thè work Fritz Miiller,

54

MICHAEL T. GHISELIN

switched to Crustacea, a move that put him in a good

position to understand Darwin’s approach. Initially

Dohrn was very enthusiastic about ontogeny as evi-

dence for phylogeny, but his own research as well as

that of other workers ultimately proved disappoint-

ing. Miiller had suggested that thè zoea might have

given rise to thè insects, and Haeckel endorsed this

view. Dohrn thought he had found vestiges of thè

zoea’s defensive spine in insect embryos, but ultima¬

tely had to give that up.

In 1870 Dohrn published an anthology of papers

that he had recently published on arthropod phylo-

genetics. The introduction to thè second half specu-

lated, noncomittally, that thè Arthropoda might be

polyphyletic. In 1871 he published thè first part of a

paper, one that was never completed, that represents

at once thè end of his earlier, ontogenetic, approach

and thè beginning of his new, physiological one. On

thè one hand it treats thè phylogeny of thè Crustacea

from a strongly recapitulationist point of view. The

nauplius is compared to larvai annelid and treated as

thè ancestral form. The zoea is an modifìed nauplius,

which had added segments at thè posterior and

of thè body. If thè recapitulationist account were

true, this made sense from a physiological point of

view — as an adaptation to increasing body size.

Invoking such functional explanations, Dohrn de-

veloped an adaptive, physiological scenario for thè

phylogeny of thè Crustacea. He attributed a great

deal to thè division of labor among appendages, and

to thè various appendages changing their functions.

His scenario also includes thè complete loss of cer-

tain features, such as thè nauplius and thè zoea in

ontogeny and thè carapace and thè eye stalks in thè

adult. When he did so he related such changes in en-

vironmental circumstances, such as moving into

fresh water or to a benthic habitat. The ostracodes

had undergone a secondary reduction in size, and

were therefore secondarily simplifìed in some res-

pects. A second fragment of this work appeared as an

appendix to his book on thè origin of vertebrates (see

below). He tried to account for thè origin of thè Rhi-

zocephala using Anelasma , a parasite of sharks as a

model. The scenario was indeed plausible, but there

were two problems. First, he put thè solution to thè

problem in thè hands of Robby Kossmann, who did

thè empirical work and got thè credit (Kossmann,

1873). Second it makes sense as a sort of model, but

thè rhizocephalans evidently branched off much too

early to be directly derived from whithin this particu-

lar group.

Dohrn’s functional explanations for thè evolution

of crustaceans were by no means unreasonable, and

ones like them have continued to play an important

role in crustacean phylogenetics. The main problem

with his phylogenetics was not thè functional aspect,

but rather that thè strict application of thè recapitula¬

tionist view became a kind of procrustean bed, and

thè notion that thè nauplius and thè zoea represent

adult ancestors became increasingly untenable as

data on crustacean larvae accumulated. His critics

pointed out, and Dohrn admitted, that it would be

easier to start with an annelid having many segments

as thè ancestral precursor of thè arthropods, and

have something like that evolve an exoskeleton.

Then it became a fairly straightforward matter to de-

velop a scenario in which thè adult crustaceans had

undergone thè sort of division of labor and function¬

al reorganization that Dohrn had envisioned. And

there would stili be a place for evolving larvae and

changes in size in response to changing conditions of

existence.

Once w e see that thè embryological program was

breaking down, it makes a great deal of sense that

Dohrn would emphasize thè physiological approach

even more strongly. The connection between his

work and that of Darwin is easily established. They

began to correspond about crustacean phylogenetics

in 1867 and met at Darwin’s home on September 26,

1870. Much of thè extant correspondence (Groeben,

1982) relates to thè founding of thè Zoological Sta¬

tion at Naples, which was a work of administrative

and organizational genius, but one that diverted

Dohrn’s attention from thè sort of phylogenetic work

that was thè raison d’ètre for thè laboratory itself.

Darwin, who was an enthusiastic supporter of thè

laboratory, sent Dohrn a copy of The Expression of

thè Emotions in Man and Animals (Darwin, 1872). It

arrived on November 13, 1972. Dohrn read it imme-

diately. His review of this book, in English, appeared

thè following summer (Dohrn, 1873). The Expression

of thè Emotions is a very good specimen of Darwinian

evolutionary psychology and evolutionary physiolo¬

gical anatomy, and Dohrn rightly interpreted it as an

example of how that kind of Science might be done.

For example, thè hearing of teeth, originally prepara-

tory to combat, persists as an emotional expression

or signal. Dohrn suggests that thè «book derives its

chief interest from being a successful attempt to

trace thè origin of special functions, to introduce thè

theory of Evolution into thè domain of physiology».

He proposes that thè practice of separating morpho-

logy from physiology is no longer possible, and «that

thè new task of physiology will be to investigate thè

origin of functions.»

Darwin’s theory had come under attack by one of

his most skillful critics, Saint George Mivart (1871),

among other things on thè grounds that Darwin had

no explanation for thè origin of new structures. Ac-

tually Darwin had anticipated this criticism, and res-

ponded more fully in later editions of thè Origin of

Species. Henri Milne Edwards (1851a) had maintai-

ned that organs could be «borrowed» from unrelated

groups, but Darwin of course realized that he had to

rule out such notions if his theory was true. New or¬

gans had to evolve from pre-existing ones, and as

suggested above, he used this assumption as a guide

to phylogeny. Be this as it may, Dohrn was provoked

by Mivart’s criticisms, and wrote an essay entitled

Die Ursprung der Wirbelthiere und das Princip des

Functionswechsels (Dohrn, 1875), which Dohrn trans-

lated, in a letter to Darwin dated February 7, 1875 as

The Origin of Vertebrates and thè Principle of Succes-

sion of Functions. His use of thè word «succession»

instead of «change» for thè German Wechsel is sig¬

nificane for it suggests that thè process is a very or-

derly one. And indeed this is clear from thè text. An

organ or other part starts out having a main function

and a subsidiary function. In response to selection,

thè subsidiary function becomes increasingly im¬

portant relative to thè main function, and finally be¬

comes thè main function, and, as a result, thè entire

organ is transformed. W e now have plenty of exam-

ples of this sort of transformation, and it is a com¬

mon part of our scenarios for thè evolution of things

like mammalian inner ear bones. Having a scenario

CHARLES DARWIN, FRITZ MULLER, ANTON DOHRN, AND THE ORIGIN OF EVOLUTIONARY PHYSIOLOGICAL ANATOMY

55

in which thè intermediates change through a series

of functionally plausible intermediates with an or-

derly replacement of functions is one canon of evi-

dence that at least some phylogeneticists endorse.

And thè principle is generally accepted as a major

contribution to thè study of evolutionary mecha-

nisms, although often ignored by phylogeneticists

(Mayr, 1960).

Dohrn illustrated his principle by means of con¬

crete examples that have largely been refuted and

many of which were excessively speculative even at

thè time. He tried to derive thè vertebrates directly

from annelids, and to make thè tunicates degenerate

vertebrates. The annelid theory in one form or ano-

ther remained viable for quite some time, and in that

sense was by no means a failure. Indeed, new mole-

cular data have made some sort of annelid theory a

very good possibility. Segmentation in both protos-

tomatous and deuterostomatous eucoelomates is

controlled in ontogeny by very similar mechanisms,

and sequence data on ribosomal RNA indicate that

segmentation was more widespread than has been

thought (Ghiselin, 1988).

Dohrn also got considerable credit for thè notion

that a great deal of regression takes place. But al¬

though Dohrn’s scenarios for vertebrate evolution

were suitable from thè point of view of explaining his

physiological principles, they were highly speculative

and not thè sort of thing that would be accepted

without much further evidence. This left him open

to attacks by hostile critics, including Haeckel and

Gegenbaur.

As thè director of thè most important zoological

laboratory in thè world, Dohrn was in an excellent

position to push on with empirical research and to

get his views known through personal contacts and

publication. Visiting investigators naturally took an

interest in Dohrn’s work and helped to publicize it.

Furthermore he had a scientifìc staff that helped to

run thè Station and also did research. This included

work on taxonomic monographs that appeared as

thè Fauna und Flora des Golfes von Neapel und an-

grenzenden Meeres-Abschnitte. The third of these mo¬

nographs was by Dohrn (1881) and dealt with thè

Pantopoda. Dohrn was by no means through with

thè arthropods.

The Pantopoda, or Pycnogonida, are commonly

called sea spiders, although their relationships to

true spiders and other aracnids are highly problemat-

ic even today — and largely for thè same reasons that

they were both a challenge and an opportunity to

Dohrn. Highly modified arthropods, with small bo-

dies and long legs, they do have sort of a spider-like

appearance. To explore this possibility, one might try

to see if they had thè same generai arrangement of

limbs and segments as a spider or other arachnid.

Proceeding as comparative anatomists usually do

when dealing with such problems, one might look at

thè front end of thè body and find a pair of claw-

bearing appendages that look like chelicerae, follo-

wed by a pair of what look like pedipalps, of a spider

or other arachnid. Then one might observe that at

thè rear there are four pairs of walking legs, again,

like a spider or other arachnid. The trouble is that

there is one additional pair of appendages between

thè first two and thè last four. Much of thè history of

pycnogonid comparative anatomy has been an effort

to account for that extra pair of limbs, and just about

everything one might think of has been suggested:

loss of a segment in arachnids, duplication or subdi-

vision of a segment in pycnogonids, non-homology

of thè posterior four pairs of limbs. The comparative

anatomisti problem is rendered all thè more frus-

trating because thè posterior end of thè body has

been reduced, and because there may be several ge-

nital openings rather than a single pair located in a

place that is diagnostic of some other group of ar¬

thropods. In thè middle of thè nineteenth century

that generally meant thè crustaceans, though we

should point out that at that time Crustacea was

often used in a broad sense that included such things

as trilobites and Limulus.

Dohrn (1869) had studied thè embryology of pyc¬

nogonids in some detail during a visit to Scotland in

1868. He found that thè young stage has three ante-

rior appendages, and, in conformity with his basic

approach at thè time, concluded that this larva was a

nauplius. However, although later development see-

med like that of crustaceans, he found no sign of a

zoea, which would be diagnostic of thè Crustacea.

Therefore he concluded that although thè pycnogo¬

nids are related to thè Crustacea, they branched off

earlier. He ruled out any relationship to thè arach¬

nids on thè basis of what he called thè seventh pair of

appendages not being present.

By thè time he wrote his monograph a great deal

more information about thè pycnogonids was avail-

able. Also he had repudiated his recapitulationist

views on thè nauplius and thè zoea. He provided de-

tailed anatomical and systematic descriptions of thè

animals, and attempted a provisionai classifìcation.

His monograph was thè basis for all subsequent work

(Helfer and Schlottke, 1935) on a group that conti-

nues to frustrate efforts to develop a satisfactory phy-

logenetic arrangement or even come up with a good

tree (see Hedgpeth, 1947, 1954; Fry, 1978). Dohrn

agreed that thè pycnogonids, like other arthropods,

are modified annelids, and on thè basis of this com-

parison he had some insights concerning thè com¬

mon ancestor of thè group. It would have had a se¬

ries of relatively undifferentiated metameres with

limbs or modified limbs. Genital openings on several

of these were part of that homogeneity and indicated

an early divergence of thè pycnogonids from their

closest extant relatives. The animals were highly mo¬

dified at both ands of thè body. At thè front end

there was a suctorial feeding apparatus that had no

obvious homologue in any other arthropod. At thè

posterior, there had been much reduction, with loss

of many segments and no abdomen persisting as a

distinct body region. Various organs such as thè go-

nads had been displaced into thè legs.

Dohrn’s treatment of thè larvae and thè «extra»

pair of appendages was affected by recent advances

in thè reproductive biology of thè group. Pycnogo¬

nids, as a generai rule, feed suctorially with their mo¬

dified proboscis, and might be considered a kind of

ectoparasite. Pycnogonid larvae, unlike those of ma¬

rine crustaceans and, indeed, unlike thè generality of

marine invertebrates, are not motile creatures that

disperse and settle at a suitable habitat. Rather they

are not motile at all, but are transported by their par-

ent. Interestingly enough, it is not thè mother, but

thè father, who cares for thè young. This had come

as something of a surprise, but, as Dohrn realized,

there are other animals in which thè father cares for

56

MICHAEL T. GHISELIN

thè young but thè mother does not, such as sea-hor-

ses and their relatives. The eggs are transferred to his

body, where they develop, and he delivers them to

thè appropriate place. The «extra» limbs («ovigers»)

are present in all male pycnogonids with thè sole

known exception of one species of thè genus Pycno-

gonum and in thè females in some species. It is now

known that thè father produces a kind of cement,

and that thè ovigers process this so as to hold thè

young together. Dohrn thought that thè ovigers of

females are strictly vestigial, and indicated that both

parents had previously cared for thè young (page 93).

As it turns out, thè ovigers are also used by some

pycnogonids in cleaning thè body, so an alterna¬

tive scenario becomes available, one with a Funk-

tionswechsel in which thè main function was clean¬

ing and thè subsidiary function of parental care

evolved in males and thè organ itself was lost in

many females.

Dohrn rejected thè notion of Semper (1874) that

thè ovigers were a «new formation» on thè grounds

that thè animals would initially have had to carry thè

eggs on limbs that did not yet exist (p. 92), and com-

pared new formations in generai to special creations.

He preferred to consider thè mouthparts and ovigers

as having been produced through Funktionswechsel

from limbs. A Darwinian approach is capable of

accounting for thè origin of new parts and features,

but only with difficulty, whereas reductions and

secondary losses are a matter of routine. So it

stands to reason that Dohrn would want to have thè

ovigers be a primitive feature rather than a secondary

acquisition, and would accept thè consequences of

that, including an early divergence of thè pycnogonid

lineage.

Manton (1978) insists that thè pycnogonids have

indeed added a limb at this point, on thè grounds of

similarities in locomotory functional anatomy bet-

ween pycnogonids and arachnids. She made this

seem more plausible on thè grounds that within thè

group there are a few isolated cases of secondary in-

creases in thè number of appendages, though these

are morphologically similar to thè posterior appen¬

dages. The generai rule in arthropods is that thè

number of segments has become gradually more st-

able beginning at thè front end and proceeding to-

ward thè rear. Adding a segment at thè front end is

stili implausible, and given a modest amount of con-

vergence and parallelism, plus some conflicting evi-

dence, a somewhat earlier derivation of thè pycnogo¬

nids without recourse to such an addition remains a

very reasonable interpretation. But even if that inter-

calation has in fact occurred, it is simply an unusual

exception to a generally valid rule, not grounds for

rejecting thè rule altogether.

Given a model of a hypothetical ancestral pycno¬

gonid, Dohrn was in a good position to do some cla-

distics with a functional aspect. He could polarize

thè characters on thè basis of his model, and also jus-

tify thè direction on thè basis of adaptive signifi-

cance. He thought that thè group was relatively ho-

mogeneous, and therefore decided not to subdivide

it into taxa of high rank. There had been a modest

adaptive radiation with some diversifìcation in feed-

ing habits and way of life. At least for some charac¬

ters it was a relatively straight-forward matter to de¬

cide which conditions were primitive and which deri-

ved. The whole group showed a trend from ovigers

being present in both sexes, to ovigers being present

in just thè males. The first appendage began with a

well developed pincer, then had a rudimentary one,

or thè appendage was lost altogether. The second ap¬

pendages also might be lost. The number of genital

openings declined from three pairs to two, and finally

to just one pair. I mention only some of these trends.

There was a crude correlation between these mo-

difications, so that thè genera Fycnogonum and Rhyn-

chothorax , united in thè family Pycnogonidae, sha-

red a number of them. The functional reason for re-

duction of limbs was thought to be that thè suctorial

apparatus had become thè main organ of feeding and

accessory mouthparts were no longer necessary. But

given that these changes all go in one direction, they

are apt to give rise to a gradai classifìcation — one

that simply ranks animals according to whether they

are relatively primitive or advanced. They are thè

sort of innovations that are apt to be subject to paral-

lel evolution, just like thè opisthobranch gastropods

that evolve polyphyletically from snails into slugs

(Ghiselin, 1966; Gosliner and Ghiselin, 1984). Under

such conditions one needs derived characters that

are also divergent if thè result is to be clades rather

than grades. It is therefore not surprising that Dohrn

himself expressed dissatisfaction with his System,

and that subsequent workers have been likewise di-

sappointed.

Dohrn and his employees and supporters pushed

on with research on thè «lower» vertebrates, espe-

cially sharks, in order to develop his ideas about ver¬

tebrate origins. The Mittheilungen of thè Station, its

house organ, devotes many publications to his Pro¬

ject. Although he failed to justify thè annelid theory,

Dohrn did make important contributions to compa¬

rative vertebrate anatomy, thanks especially to his

work on thè embrology of sharks. I will not go into

thè details at this time, but should mention that a de-

tailed acount of his work has been presented by

Kuhn (1950). Rather it is important that w e note

Dohrn’s influence upon thè Russian school of evolu-

tionary morphology, especially its founder, A. N. Se-

wertzoff (1866-1936) (see Ghiselin, 1980). Sewertzoff

and his successor Schmalhausen freely and openly

acknowledged Dohrn’s contribution. The Ursprung

was treated as canonical literature, and Schmalhau¬

sen (1937) wrote a long and appreciative introduction

to thè Russian translation.

Sewertzoff visited thè Station in 1897, in order to

study thè embryology of fish, including teleosts, se-

lachians and cyclostomes. Sewertzoff (1899) was ob-

viously working on thè same kind of problems that

interested Dohrn, but thè influence of Dohrn upon

Sewertzoff is not immediately apparent. It was only

much later that Sewertzoff (1927, 1928, 1931) brought

thè work of Dohrn and others on Funktionswechsel

and related topics up to date. Sewertzoff (1931) also

wrote one of thè best discussions on thè relation-

ships between ontogeny and phylogeny. He stressed

thè point that recapitulation occurs in a straight-for¬

ward manner only when there has been terminal ad¬

dition. Sewertzoff (1931: 248) expresses regret that in

his earlier works (Sewertzoff 1912, 1928) he had over-

looked how Fritz Mùller (1864) had presented early

divergence as an alternative to terminal addition. He

accuses Darwin, along with Haeckel and Weisman,

of not having appreciated that point. And yet, as we

have seen, Darwin was Miiller’s source on that very

CHARLES DARWIN, FRITZ MÙLLER, ANTON DOHRN, AND THE ORIGIN OF EVOLUTIONARY PHYSIOLOGICAL ANATOMY

57

point! If Sewertzoff did not do proper justice to Dar¬

win, and if his mature appreciation of Miiller was at

least in part a sort of rediscovery, then it seems likely

that thè Russian endorsement of Dohrn was at least

partly retrospective as well.

Manton (1977) presents thè functional approach as

someting that was invented by H. Graham Cannon,

which may have been true of her own functional ap¬

proach, hardly does justice to biology in generai. I

find that although Manton (1977, 1978) cites Dohrn’s

monograph on thè pycnogonids, she does so only

with reference to thè illustrations, not thè text, and

that may explain thè oversight. This is, of course, no

isolated incident. Systematists, like other scientists,

work within a very narrow disciplinary context. They

all too often overlook thè accomplishments of those

who specialize on taxonomic groups other than their

own, neglect thè older literature and that in foreign

languages, and quite generally stick to tradition and

routine.

Acknowledgements — William Newman and Joel

Hedgpeth gave me thè benefit of their immense eru-

dition about cirripedes and pycnogonids in reviewing

and discussing thè manuscript in its early stages.

Detailed comments on thè manuscript by Cesare Ba¬

roni-Urbani, Robert J. O’Hara, Alessandro Minelli,

and Francesco Scudo, and informai discussion by

other participants in thè Milan workshop are grate-

fully acknowledged.

REFERENCES

Barlow N. (Ed.), 1959 - The autobiography of Charles Darwin

1909-1982. With Originai Omissions Restored. Harcourt,

Brace, New York: 253 pp.

Burkhardt F. & Smith S. (Eds.), 1988 - The Correspondence of

Charles Darwin. Cambridge University Press, Cambridge, 4:

XXXVI + 711 pp. (1847-1850).

Darwin C., 1851 - A Monograph on thè Sub-Class Cirripedia,

with Figures of all thè Species. The Lepadidae; or, Pedunco-

lated Ciripedes. Ray Society, London. XII + 400 pp. (PI. I-X).

Darwin C., 1854 - A Monograph on thè Sub-Class Cirripedia,

with Figures of all thè Species. The balanidae (or Sessile Cir¬

ripedes); thè Verrucidae, Etc., Etc., Etc. Ray Society, Lon¬

don. viii + 684 pp. (Pls. I-XXX).

Darwin C., 1865 - On thè movement and habits of climbing

plants. J. Linn. Soc., London (Bot.), 9: 1-118.

Darwin C., 1868 - The Variation of Animai and Plants under Do-

mestication. lst ed. 2 vols. John Murray, London.

Darwin C., 1872 - The Expression of thè Emotions in Man and

Animals. lst ed. John Murray, London: VI + 374 pp.

Dohrn A., 1869 - Untersuchungen iiber Bau und Entwickelung

der Arthropoden. 2. Ueber Entwicklung and Bau der Pycno-

goniden. Jena. Z. Naturwiss., 5: 138-157. (Taf. V, VI).

Dohrn A., 1870 - Untersuchungen iiber Bau und Entwicklung

der Arthropoden. 2 vols. Wilhelm Engelmann, Leipzig: V +

VI + 193 pp. (XVII Taf.).

Dohrn A., 1871 - Geschichte des Krebsstammes, nach embryolo-

gischen, anatomischen und palaeontologischen Quellen.

Ein Versuch. Jena Z. Naturwiss., 6: 96-156.

Dohrn A., 1873 - The expression of thè emotions in man and ani-

mais, by Charles Darwin. Academy, 4 (2 June): 209-212.

Dohrn A., 1875 - Der Ursprung der Wirbelthiere und das Princip

des Functionswechsels. Genealogischen Skizzen von Anton

Dohrn. Wilhelm Engelmann, Leipzig: XV + 87 pp.

Dohrn A., 1881 - Die Pantopoden des Golfes von Neapel und der

angrenzenden Meeres-Abschnitte. (Fauna und Flora des

Golfes von Neapel, III). Wilhelm Engelmann, Leipzig: Vili +

252 pp. (XVII Taf.).

Fry W. G., 1978 - A classification within thè pycnogonids. Zool.

J. Linn. Soc., 63: 35-58.

Ghiselin M. T., 1966 - Reproductive function and thè phylogeny

of opisthobranch gastropods. Malacologia, 3: 327-378.

Ghiselin M. T., 1969 - The Triumph of thè Darwinian Method.

lst ed. University of California Press, Berkeley: X + 287 pp.

Ghiselin M. T., 1975 - The rationale of pangenesis. Genetics, 79:

47-57.

Ghiselin M. T., 1980 - The failure of morphology to assimilate

Darwinism. In: The Evolutionary Synthesis. (Eds: Mayr,

Ernst; Provine, William B). Harvard University Press, Cam¬

bridge: 180-193.

Ghiselin M. T., 1985 - Mayr versus Darwin on paraphyletic taxa.

Syst. Zool., 34: 430-462.

Ghiselin M. T., 1988 - The origin of molluscs in thè light of mo-

lecular evidence. Oxford Surv. Evol. Biol., 5: 66-95.

Ghiselin M. T., 1992 - Review of The Meaning of Evolution, by

Robert J. Richards. Syst. Biol., 41: 497-499.

Ghiselin M. T. & Jaffe L., 1973 - Phylogenetic classification in

Darwin’s Monograph on thè Sub-class Cirripedia. Syst.

Zool., 23: 132-140.

Gosliner T. M. & Ghiselin M. T., 1984 - Parallel evolution in op¬

isthobranch gastropods and its implications for phylogenetic

methodology. Syst. Zool., 33: 255-274.

Groeben C. (Ed.), 1982 - Charles Darwin 1809-1882, Anton

Dohrn 1840-1909: Correspondence. Macchiaroli, Napoli:

118 pp.

Haeckel E., 1866 - Generelle Morphologie der Organismen.

Allgemeine Grundziige der organischen Formen-Wissens-

chaft, mecanisch begriindet durch die von Charles Darwin

reformierte Descendenz- Theorie. 2 vols. Verlag von Georg

Reimer, Berlin: XXXII + 574 + CLX + 462 pp. (Taf. I-II,

I-VIII).

Hedgpeth J. W., 1947 - On thè evolutionary significance of thè

Pycnogonida. Smithsonian Mise. Coll., 106 (18): 1-54. (PI. I).

Hedgpeth J. W., 1954 - On thè phylogeny of thè Pycnogonida.

Acta Zool., Stockholm, 35: 193-213.

Helfer H. & Schlottke E., 1935 - Pantopoda. In: Klassen und

ordnungen des Tierreichs. (Ed: Bronn, HG) Akademische

Verlagsgesellschaft, Leipzig, 5.4.2: 314 pp.

Heuss T., 1948 - Anton Dohrn. 2nd ed. Rainer Wunderlich Verlag

Hermann Leins, Stuttgart. 448 pp.

Kossmann R., 1873 - Suctoria und Lepadidae. Untersuchungen

iiber die durch Parasitismus hervorgerufenen Umbildungen

in der Famille der Pedunculata. Habitlitationsschrift ge-

nehmigt von der Philosophischen facultàt der Universitàt

Heidelberg. Stahel, Wiirzburg: 32 pp. (Taf. I-II).

Kuhn A., 1950 - Anton Dohrn und die Zoologie seiner zeit. Pub.

Staz. Zool., Napoli (Supplemento): 1-205.

Manton S. M., 1977 - The Arthropoda: Habits, Functional Mor¬

phology and evolution. Clarendon Press, Oxford: XXII +527 pp.

Manton S. M., 1978 - Habits, functional morphology and thè

evolution of pycnogonids. Zool. J. Linn. Soc., 63: 1-21.

Mayr E., 1960 - The emergence of evolutionary novelties.

In: The Evolution of Life: its Origin, History and Future.

(Ed: Tax, S). (Series Ed: Tax, S. Evolution after Darwin, Vo¬

lume 1). University of Chicago Press, Chicago: 349-380.

Milne-Edwards H., 1834-1840 - Histoire Naturelle des Crusta-

cés, Comprenant l’Anatomie, la Physiologie, et la Classifìca-

tion de Ces Animaux. 3 vols. Libraire Encyclopédique de

Roret., Paris: XXV + 468 + 531 + II + 638 + 32 pp. (Atlas 32

pages + XLII Planches).

Milne-Edwards H., 1851a - Introducion à la Zoologie Générale

ou Considérations sur les Tendaces de la Nature. Victor

Masson, Paris: IV + 180 pp.

Milne-Edwards H., 1851b - Observations sur le squelette tégu-

mentaire des crustacés décapodes, et sur la morphologie de

ces animaux. Ann. Sci. nat. Zool., 3 (6): 221-291. (PI. 8-11).

Mivart S. G., 1871 - On thè Genesis of Species. Macmillan, Lon¬

don: XVI + 296 pp.

Mùller F., 1862 - Die Rhizocephalen, eine neue Gruppe schma-

rotzender Kruster. Arch. Naturg., 28 (1): 1-9. (Taf. I).

Mùller F., 1864 - Fùr Darwin. Wilhelm Engelmann, Leipzig: III +

91 PP-

Mùller F., 1869 - Facts and Arguments for Darwin: with Addi-

tions by thè Author. Translated by W. S. Dallas. John Mur¬

ray, London: VII + 144 pp.

Newman W. A., 1983 - Origin of thè Maxillopoda; urmalacostra-

can ontogeny and progenesis. In: Crustacean Phylogeny.

(Ed: Schramm, Frederick R). (Series Ed: Schramm, Frede¬

rick R. Crustacean Issues, 1). Balkema, Rotterdam: 105-119.

Newman W. A., 1993 - Darwin and cirripedology. In: Crustacean

Issues. (Ed: Schramm, F. R.). A. A. Balkema, Utrecht: 1-67.

O’Hara R. J., 1988 - Homage to Clio, or, toward an historical phi-

losophy for evolutionary biology. Syst. Zool., 37: 142-155.

58

MICHAEL T. GHISELIN

Richards R. J., 1992 - The Meaning of evolution: thè Morpho-

logical Construction and Ideological Reconstruction of

Darwin’s Theory. University of Chicago Press, Chicago: XV +

205 pp.

Schmalhausen I. I., 1937 - Anton Dohm and his role in thè deve-

lopment of evolutionary morphology. In: The Origin of Verte-

brated Animals and thè Principle of Change of Function, by

Anton Dohm, Translated from thè German by B. I. Balinski.

(Ed. Schmalhausen, I. I.). Ogiz, Moscow: 7-78. (In Russian).

Semper C., 1874 - Ueber Pycnogoniden in ihre in Hydroiden

schmarotzenden Larvenform. Arò. Zool.-Zootom. Inst.,

Wurzburg, 1: 264-286.

Sewertzoff A. N., 1927 - Uber die Beziehungen zwischen der

Ontogenese und der Phylogenese der Tiere. Jena. Z. Natur-

wiss., 63 (1, 4 Màrz): 51-180.

Sewertzoff A. N., 1928 - Uber die Prinzipien der phylogenetis-

chen Entwicklung. Zoo/. Zhur., 8 (3): 139-148. (In Russian).

Sewertzoff A. N., 1931 - Morphologische Gesetzmàssigkeiten

der Evolution. Verlag von Gustav Fischer, Jena: XIV + 371 pp.

Sewertzoff A. N., 1932 - Ueber die Bedeutung des Princips der

Substitution und einiger anderer Principien in der Phyloge¬

nese. Arch. Zool. Ita!., 16: 128-139.

Walker G., 1983 - A study of thè ovigerous frena of barnacles.

Phil. Trans. Roy. Soc., London, B218: 425-442.

Michael T. Ghiselin: Department of Invertebrate Zoology and Center for thè History and Philosophy of Science

California Academy of Sciences, Golden Gate Park - San Francisco, California 94118-4599 U.S.A.

Systematic Biology as an Historical Science

Memorie della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano

Volume XXVII - Fascicolo I - 1996

James R. Griesemer

Some concepts of historical Science

«The nourishing fruit of thè historically understood contains time as a precious but tasteless seed.» -

Walter Benjamin

Abstract - The goal of this paper is to explore thè concept of historical Science, Many analysts of Science distinguish

between historical and ahistorical Sciences to argue that some practices are more «scientific» than others, that thè distinc-

tion supports a particular view of proper scientific method, or that some are mere pseudo-sciences. After discussing these

reasons for calling a Science historical, six different analyses of thè concept of historical theory or Science are discussed.

I conclude in favor of a pragmatic view, drawing on Danto’s analysis of narrative, in which a Science is historical to thè

extent that it admits narrative as contributing to understanding.

The goal of this paper is to explore thè concept of

historical Science. It is claimed that evolutionary

theory and thè biological Sciences that use and deve-

lop it, e.g. systematics, are historical Sciences. Such a

claim is sometimes used to differentiate among

Sciences, e.g. to classify them as «hard» or «soft».

Since many authors discussing thè nature of syste-

matic biology, theory, or practice assume a clear dis-

tinction between historical and ahistorical, it is help-

ful to examine several such concepts. The approach

used here is philosophical: examining proposed dis-

tinctions between historical and ahistorical Sciences

(or theories) and criticizing them for failing to distin¬

guish among Sciences (or theories) that common in-

tuition distinguishes. Since thè aim in making such

distinctions is either to aid understanding of thè na¬

ture of thè Sciences or to make value judgments (e.g.

to set priorities for funding or ranking for prestige),

thè philosophical exercise has practical merit. The

aim is not, however, to criticize claims in thè philo¬

sophical and biological literature in order to establ-

ish which philosophical «school of thought» has thè

correct analysis of Science. Rather, thè practical

merit in thè philosophical exercise is to defend thè

intellectual autonomy of systematics against thè cri-

ticisms of theoretical and sociologica! reductionists.

Why cali a Science historical?

Three reasons one might cali a Science historical

are to argue that: (1) a Science, for being historical, is

no less legitimate or valuable than other, ahistorical

Sciences; (2) a certain model of explanation that ser-

ves as a standard of scientific acceptability, e.g. Hem-

pel’s deductive-nomological or covering-law model,

applies to thè Science even though nothing like

Hempel’s ideal schema appears in thè main texts of

thè practitioners; (3) thè kind of warrant, or justifìca-

tion, of knowledge or understanding claims is dis-

tinct from that of ahistorical Science. Three more

reasons just negate thè first three: (T) in being histo¬

rical, a Science is distinctly illegitimate, unfounded,

or at least inferior to ahistorical Science; (2') If Hem-

pel’s covering-law model of explanation (or some-

thing like it) does not apply to a subject, that subject

is not a Science at all; (3') The kind of warrant or

justification in historical Science in thè same as for

ahistorical Science, and therefore thè knowledge pro-

duced by historical Science is weaker because thè

warrant is generally less for its claims.

I will consider these reasons before discussing

six conceptions of what makes a Science historical

because they color one’s reading of thè concept of

«historicality». The different concepts suit different

purposes, and it is not at all clear which reasons and

concepts should be judged compatible. I shall not

consider thè compabilities in detail, but only review

four concepts and offer two more.

Positive and negative reasons are considered to-

gether because I do not aim to endorse arguments

committed to one side or thè other. Scientists engag-

ing in turf battles for legitimation, authority, domi-

nation, money, power, students, laboratory space, or

glory, often invoke thè legitimacy reason in argu¬

ments to secure places in a «pecking order» for dif¬

ferent Sciences or to reject hierarchies of authority

and social status altogether. The others are more ty-

pically used by historians or philosophers concerned

to formulate generai principles of Science or metho-

dological principles for their own disciplines.

Typically, authority hierarchists place physics and

other physical Science at thè top. Then comes biolo¬

gy and thè «historical» parts of geology and other

earth Sciences, then psychology, and then thè lowly

social Sciences like sociology and anthropology.

Equally typically, anti-hierarchists argue for some

sort of «pluralism», with all Sciences on an equal

footing. For example, in «A plea for thè high status

of naturai history», Stephen Jay Gould (1989, 280-81)

takes Nobel laureate physicist Louis Alvarez to task

for likening paleontologists to stamp collectors and

calling them «not very good scientists». Gould de-

fends thè autonomy and authorithy of naturai histo-

60

JAMES R. GRIESEMER

ry by invoking thè power of historical interpretation

on thè one hand and thè ignorance of physicists

about naturai history on thè other.

The second reason, regarding thè nature of scien-

tific explanation, typically concerns philosophers of

history, whose project this century was transformed

by Hempel’s 1942 essay, «The Function of General

Laws in History». This essay set thè stage for his con-

troversial covering-law model of explanation (Hem-

pel and Oppenheim 1948; Salmon 1989) and capped

two decades of disputation about whether history

was a scientific discipline or could be reduced to one.

Along with a number of other developments in thè

philosophy of empiricism that grew out of thè logicai

positivism of thè 1920s, Hempel’s work polarized

generai discussion about Science around thè issue of

thè reducibility of thè centrai theories of one Science

to those of another. The reduction debate was driven

by three features of Hempel’s conception of explana¬

tion: (1) that, ideally, explanations are sound deduc-

tive arguments from premises including statements

of generai laws of nature and particular conditions

about thè phenomenon to be explained; (2) that

explanation is thè core project of any Science; and

(3) that since deduction allows thè explanation of a

law by more generai or «logically powerful» ones, thè

laws of one Science might be explained by those of

another, more powerful Science. This last feature

provides thè basis for a conception of thè growth of

scientific knowledge as thè reduction of less power¬

ful theories to more powerful ones.

When philosophers turned their attention to

Sciences like geology, systematics, and evolutionary

biology, it proved difììcult to formalize thè relevant

theories along deductive lines (Flew 1959, Smart

1963, Williams 1970). The expectation of success was

formed largely through thè tacit inductive argument

that if a few select physical laws of mechanics can be

so formulated, then all of physics can and, by appeal

to principles of hierarchy and reduction, then all of

Science can.

Some of thè qualities that made formalization of

thè «soft Sciences» difficult align these Sciences with

thè humanities and social Sciences rather than with

thè physical Sciences, Goudge (1958), for example,

defended such an alignment, arguing that explana¬

tions in naturai history have more thè structure of

coherent narratives than of deductive systems. Des-

pite this, such narratives could be causai expla¬

nations. Therefore, according to Goudge, thè philo-

sophical model of deductive arrangement under

generai causai laws, which is lacking in naturai histo¬

ry narratives, cannot lay exclusive claim to causai ex¬

planation. Nor, therefore, can physics lay claim to a

scientific method superior to that of thè «historical»

Sciences (Goudge 1958, 202).

The narrative quality of Darwin’s adaptive expla¬

nations is manifest in thè structure of this argument

for evolution and naturai selection (e.g. Beer 1985;

Gould 1986). This «literary» quality looked proble-

matic to those logicians who rejected as meaningless

all statements lacking means of empirical verifìca-

tion. They accordingly tried to explain Darwin’s

theory away (e.g. Nagel 1961 for teleological explana¬

tion in generai), or to argue that such Sciences are in-

ferior Science or even pseudo-science (e.g. Popper

1957, who later changed his mind about naturai se¬

lection, see Popper 1972, 1978). Smart (1963) argued

that since there are no generai laws for particular

species, evolutionary biology was not scientific. This

statement helped provoked thè elaboration of thè

philosophical analysis of species as individuals rather

than kinds or classes (Ghiselin 1974, Hull 1980). The

species-as-individuals view supports an argument

that there should not be laws about particular species

and that philosophers and others misjudged evo¬

lutionary theory in claiming it had no laws and was

unscientifìc. Rather, they had been looking in thè

wrong place for laws.

Calling a Science historical because it fails to redu¬

ce to physics is a reason I will not explore further.

I do not believe explanation, as laid out by thè Hem-

pelian tradition, is necessarily thè centrai project of a

Science, nor do I believe that there is necessarily any

such beast as thè «core theory» of a Science in Hem¬

pel’s terms. My reasons trace to suspicions of vague-

ness and ambiguity in thè concept of «theory» and

thè likelihood that holding such concepts in high re-

gard will lead to error, or worse.

Although thè analytical philosophy of history

(Danto 1985) has done much to widen thè scope of

generai philosophical discussion on thè topic of ex¬

planation, thè latter’s ultimate purpose is too nar-

rowly epistemological to serve my goals. Philosophi¬

cal theories of explanation distinguish too rigidly

between «discovery» and «justifìcation». This once

useful distinction now serves only to insulate deduc¬

tive inference from thè scrutiny that other aspects of

scientific practice routinely receive by historians and

sociologists as well as philosophers of Science. The

question of what justifies deduction itself is part of

thè generai problem of justifìcation. Deduction has

become a self-justifying (or unjustifiable) axiom for

philosophy of Science. And this in tura has masked

thè important fact that logicai empiricist philoso¬

phers of Science are themselves merely using a bit of

predicate calculus as off-the-shelf technology. There

is no a priori reason one could not or should not take

narrative as an alternative basis for Science.

Justifìcation or warrant concerns thè relation bet¬

ween evidence and hypothesis, while explanation

concerns thè relation between premises in an ex-

planatory argument and conclusions, or between

questions and answers (van Fraassen 1980). Thus, re-

gardless of what purposes are served by invoking

scientific legitimacy or thè pattern of explanation,

a third reason to cali a Science historical is that it

differs in thè style of justifìcation from ahistorical

Sciences. That is, its evidence bears a different re¬

lation to its hypotheses. Advocates and critics of

thè distinction between historical and ahistorical

Science can agree that producing an explanation and

justifying it are logically distinct operations, and yet

disagree on whether thè distinction between styles

or types of justifìcation, and therefore between

different kinds of Science, serves any important

purpose.

Claims about warrant (reason three) are some-

times linked to thè fìrst reason through an argument

that, because Science becomes unified by a universal

logie of warrant, a Science is legitimate to thè extent

that it satisfies that logie. Scientists sometimes de-

fend a particular Science against thè charge that it is

inferior or pseudo-science by arguing for thè epistem¬

ological unity of Science (and against a distinction

between historical and ahistorical Science). But

SOME CONCEPTS OF HISTORICAL SCIENCE

61

scientists sharing thè goal of defending thè legitima-

cy of particular Sciences can fall on either side of thè

unity of Science question. One can analyze history it-

self in such a way that it is scientific, and therefore

that historical Sciences are scientifìc, or one can deny

that being historical entails not being scientifìc on

grounds other than warrant and thus stili accept epis-

temological unity. On thè other hand, one can reject

epistemological unity as a goal of Science and then

nothing is entailed about whether a practice is scien¬

tifìc just in virtue of being historical. Therefore, nei-

ther commitment — to unity or disunity — is effective

in defending a Science against its critics.

Historians and philosophers of Science also pursue

common legitimation goals with different commit-

ments to epistemological unity or disunity. Some

recent essays from a symposium on evolution as a

historical Science illustrate this. Richards (1992) re-

lies on thè distinction between historical and ahisto-

rical Science, but to argue against thè Hempel model

as a basis for unity. Richards argues that Hempel’s

model gets thè nature of explanation backwards.

Hempel did not claim that acceptable explanations

in actual scientifìc practice meet thè formai condi-

tions he defined. Rather, he offered them as an ex-

planatory ideal to which reai explanations are better

or worse approximations. Reai explanations might

not meet thè ideal by failing to explicitly mention

laws, although these might be supplied by post hoc

historical or philosophical analysis in particular

cases. Hempel called such approximations «explana¬

tion sketches» that could in principle be filled in.

Many commentators have taken Hempel’s idealism

to insulate his model from thè criticism that it failed

to account for actual scientifìc explanatory practices.

Richards argues instead that historical narrative ex¬

planations — far from being mere explanation sket¬

ches — are thè ideal, and that deductive-nomological

explanations (even those meeting all of Hempel’s re-

quirements) are mere narrative sketches. Unity of

Science is preserved by standing thè logie of explana¬

tion on its head.

Hull (1992) likewise relies on thè historical/ahisto-

rical distinction and likewise argues against thè em-

phasis on laws in thè Hempel model, but on different

grounds than Richards. Hull defends a «particular-

circumstance» model of explanation against Hem-

pel’s covering-law model to capture thè sense that,

even within thè broad framework of deductive infe-

rence, in historical Sciences thè conditions or parti¬

cular circumstances rather than thè laws govern thè

character of explanations. Thus, while Richards de¬

fends epistemological unity of Science by arguing

that narrative rather than deduction unifìes explana¬

tion, Hull defends plurality of explanatory practice

within a broad epistemological unity of deductive

form.

Ereshefsky (1992) does something orthogonal to

both Richards and Hull. He rejects thè historical/

ahistorical distinction among forms of explanation

and considers thè Hempel model a useful (though

perhaps limited) paradigm. He argues instead that

evolutionary theory is historical, but because some

of its centrai entities — taxa — are a special type of

historical entity, not because its explanations are his¬

torical in form. Hull argues that thè model of expla¬

nation in evolutionary theory takes a distinctive, par-

ticularistic form because thè entities are historical,

thus accepting thè classical basis for thè historical/

ahistorical distinction in thè form of explanation.

Ereshefsky rejects thè classical basis, but accepts a

new distinction based on thè nature of thè entities

rather than thè form of explanation. He argues that

this new distinction is compatible with thè Hempel

model and thè Ghiselin-Hull philosophy of historical

individuate.

Laudan (1992) rejects thè distinction between his¬

torical and ahistorical Science, not because she sees

an alternative route to challenge Hempel’s analysis

of thè form of «proper» scientifìc explanation (Ri¬

chards, Hull) or because thè entities of some Scien¬

ces are historical entities (Ereshefsky), but because

she rejects thè question of explanatory form as

thè signifìcant one. She suggests that philosophers

of history should look again at thè literature on

scientifìc explanation (i.e., they should bring their

history of philosophy up to date). They would find

that in thè fìfty years since Hempel proposed his

model, it has ceased to be thè only viable formai

model, and is no longer thè most promising one to

many philosophers.

Laudan takes thè difference between Sciences like

geology and biology on thè one hand and physics

and chemistry on thè other to be a scientifìc question

about warrant, not a philosophical question about

thè logicai form of explanation. The scientifìc prob-

lem is to devise means of acquiring reliable knowled-

ge. She traces thè motivation to distinguish historical

from ahistorical Science to «observational diffìcul-

ties» about reconstructing thè record of thè past and

argues that thè gradient of diffìculty in this regard

among thè Sciences does not make for epistemologi¬

cal disunity, whatever form explanations in different

Sciences may take (Laudan 1992, 62). The fact that a

laboratory physicist or geneticist has less trouble re¬

constructing thè history of events in their experi-

mental set-up than does a field paleontologist tracing

a fossil record or a systematist reconstructing a phy-

logeny does not make for a difference in kind, but

only in degree. Solution to thè problem of stating thè

generai terms of scientifìc warrant does not imply

anything, therefore, about thè epistemic unity or di¬

sunity of thè Sciences.

The objective of Laudante argument is to deny an

appeal to thè complexity of geological processes and

incompleteness of thè data to sustain a distinction

between historical and ahistorical Science. Danto

(1985, 340) argues thè same point in a more generai

context: incompleteness of record is a «banal and

contingent» fact about historical data, not what

makes a practice historical. W e shall see below why

appeals to complexity and incompleteness fail to

ground thè distinction.

As far as devising means of acquiring reliable

knowledge goes, thè issue of narrative vs. deductive

form of explanations is tangential to thè epistemolo¬

gical problem of warrant (Laudan 1992, 64). The only

historical/ahistorical distinction Laudan admits is

that narrative explanation requires an additional jus-

tifìcation step: connecting parts of chronologies

using particular causai theories. The link between

use of causai theories and parts of chronologies is

important for characterizing historical Science, but a

proper analysis would show that thè distinction can

be drawn independently of arguments for or against

epistemological unity (Griesemer ms).

62

JAMES R. GRIESEMER

One may doubt that arguments pursuing any of

thè three reasons for calling a science historical can

be efìfective on thè grounds proposed. One can argue

for or against legitimacy, explanatoriness, or warran-

tability of a science while accepting or rejecting thè

claim that it is distinctively historical and while ac¬

cepting or rejecting thè claim that thè Sciences as a

whole are epistemically unified or disunified. Push-

ing further, I will argue that what makes a science

historical is a pragmatic matter of taste rather than

logie, and thè distinction is one of aesthetics and

judgment. Put differently, questions of logicai form

are distinct from questions of logicai relation and

questions of historical form are distinct from ques¬

tions of historical relation. That explanatory form

and historicality are pragmatic matters in no way for-

ces one to take up sides on thè largely sterile contro-

versies dividing relativists and realists or objectivists

and subjectivists.

What is a historical science?

I will not discuss all thè concepts needed to in-

terpret thè claim that some Sciences are historical

and others not. Concepts like «chronicle» and «nar¬

rative» are mentioned only to introduce an alterna¬

tive view of what makes a science historical. Danto

(1985) analyzes thè relevant concepts.

A good start in answer to thè question is made in

Wright, Levine and Sober (1992). In a section autho-

red by Sober and titled, «The Historical Character of

Evolutionary Theory» (48-51), four concepts of thè

historicality of historical science are discussed (cf.

Levine and Sober 1985).

The first conception is one that Sober dismisses as

trivial, failing even to demarcate evolutionary theory

from «billiard ball» mechanics. Even though I will

ultimately distinguish «historical science» from «his¬

torical theory», thè claims to follow are worth consi-

dering irrespective of whether science or theory was

thè author’s intended target.

1. A theory is historical if thè statements it explains

refer to two or more moments of time

This is trivial because any science that deals with

temporally extended entities, events, or sequences

must refer to multiple moments in time. Time here

is thè tastless seed, not thè nourishing fruit. The fact

that billiard ball mechanics refers to thè States of

balls at different times suffices to classify it as histori¬

cal according to criterion 1. Indeed, it is hard to see

how theories of any physical processes could to

otherwise, and since evolutionary theory is a theory

of certain physical processes, claim 1 does not demar¬

cate evolutionary theory from any other dealing with

physical processes, nor any science based on faets

of naturai history from other Sciences. And even if

systematics is interpreted as a theory of certain tem-

poral relations or patterns among taxa rather than

processes, it would not be distinguished from a simi-

larly interpreted physics, e.g. one interpreted in

terms of functional relations rather than causes (e.g.

Russell 1913).

It does not follow, however, that claim 1 does no

demarcation work at all. It demarcates thè Sciences

of pure abstractions — «Platonic objects of thought» —

such as mathematics and philosophy from empirical

Sciences of thè physical world. Abstract objects are

not in time, and therefore their explanations do not

require reference to moments of time.

A more promising thesis is one that Sober charac-

terizes as attributing «thè Markov property» to a

scientifìc theory. Sober (Wright et al. 1992, 48) traces

this view to Gustav Bergmann and quotes an adapta-

tion of it by Hull (1974).

2. A theory is historical when «knowledge of thè past

is necessary to predict thè future. Knowledge of thè

present alone will not do»

It is important not to overinterpret claim 2. It does

not assert that knowledge of thè past is suffìcient to

predict thè future, but only that it is necessary. If reai

physical systems exhibit chaotic dynamics, then even

very precise information about thè past may be in-

suffìcient to predict thè future (My thanks to Profes¬

sor Scudo for raising this point). Claim 2 does not

claim so much, but Sober rejects it on several

grounds. First, he points out that in population ge-

netics, standard models require only thè gene and

genotype frequencies of thè population at a given

time plus a speciflcation of thè evolutionary forces in

play at that time. If population genetics is taken to be

thè core of evolutionary theory, and one claims that

evolutionary theory is historical, then Sober’s point

has some merit: since population genetics does not

(or at least need not) have thè Markov property, evo¬

lutionary theory is not historical by criterion 2. One

may, of course, deny that population genetics is thè

core of evolutionary theory or conclude that evolu¬

tionary theory is not historical without doing serious

damage to claim 2.

Sober makes a more important second point about

references to thè past: any dynamical theory will in

practice typically require knowledge of thè past as

well as of thè present to predict thè future. In order

to predict without reference to thè past, a theory

must be dynamically and empirically suffìcient rela¬

tive to thè choice of state variables, parameters, and

state space (Lewontin 1974, Wimsatt 1980, Lloyd

1988). Otherwise, our poor knowledge of how forces

combine to produce effeets will require that to pred¬

ict w e must know things about thè temporal order in

which thè forces operated in thè past. Cartwright

(1983) makes thè same point when she argues that

mechanics is thè only example of a dynamical theory

for which there is a generai rule (vector addition)

about how to combine forces. She argues that, more

typically, thè lack of generai laws of interaction leads

to thè complex form of «phenomenological laws»

used to predict in practice. These are distinct from

thè pristine «fundamental laws» used to explain. For

a theory like evolutionary theory, one needs in addi¬

tion a lot of variables and a lot of care in their measu-

rement to avoid empirical insufficiency, which is also

required to predict a future state of an evolving Sys¬

tem from its present state alone.

Indeed, for evolutionary theory, Lewontin (1974)

suggests that we will rarely meet conditions of dyna¬

mical and empirical sufficiency to make interesting

predictions about evolutionary systems in nature.

But this failure in practice does not lead Sober to

SOME CONCEPTS OF HISTORICAL SCIENCE

63

argue that evolutionary theory is historical. He in-

stead argues against thè interpretation that flows

from claim 2. It does not follow that a theory is histo¬

rical merely due to failure to meet thè practical re-

quirements of dynamical and empirical sufficiency.

In practice, one can sometimes substitute a knowled-

ge of history for satisfaction of formai sufficiency.

But it would be a mistake to confuse this empirical

and contingent fact with a conceptually necessary

property of historical Science.

While I accept Sober’s point about theories, and

therefore his conclusion that claim 2 fails to demar¬

cate evolutionary theory from others in thè class of

dynamical theories, there are caveats. It is not clear

how far Sober’s conclusion about a rather unspeci-

fied evolutionary theory carries to other theories and

theoretical structures in evolutionary biology, e.g. to

theories of speciation, or more importantly to thè

collection of methods and assumptions that play a

role in systematics practices such as cladistic analysis

and phylogeny reconstruction. Sober (1988) argues

for thè dependency of cladistic inference on model

assumptions about thè evolutionary process, but that

does not suffice to show that cladistic practice de-

pends on any particular version of evolutionary theo¬

ry. Therefore, thè failure of claim 2 to establish thè

historical nature of evolutionary theory does not

imply that systematics is also ahistorical.

Caution must be exercised in two ways in evaluat-

ing these arguments. One is in articulating thè con-

tent and structure of theories. If theories are best

presented through models rather than axiomatized

laws, it may turn out that what can be done with mo¬

dels in practice plays a more important role that any

conceptually necessary claim about thè historical or

ahistorical nature of thè theory, making precise state¬

ment of thè latter irrelevant to understanding what it

means to say that thè theory is historical. Second, we

may be forced to distinguish between theories and

Sciences if practice is relevant. A Science in which a

theory is constructed and used to make predictions

may be historical even if thè theory itself fails thè test

of claim 2. (It should already be clear that in calling a

Science historical, I am not concerned with thè idea

that all Sciences are historical because they are prac¬

tices and that all practices are historical).

Distinguishing between a Science and a theory

leads to thè further concern that we are perhaps

being overly respectful of thè idea that prediction,

like explanation, is a relation between premises and

conclusions of arguments. The covering law model

of explanation (and by Hempel’s symmetry thesis,

prediction) not only leads us to think of prediction in

this way, but also leads to inattention to thè practice

of argumentation. Hempel was sensitive to this in his

claim to be formulating idealized concepts of expla¬

nation and prediction, not analyzing or criticizing ac-

tual scientifìc explanations. The latter amount to

mere explanation sketches in Hempel’s analysis. But

they are none thè less powerful for failing to meet

thè ideal, and if thè idealization is so stringent that it

is never met in scientifìc practice, then practice, not

thè ideal, should be thè focus of attention in trying to

understand what makes a Science historical. To thè

extent that explanatory and predictive practice fails

outside thè bounds of what is typically called «theo¬

ry», we may need to distinguish claims about histori¬

cal Science from claims of historical theories so as to

fix thè meaning of what is necessary to predict thè

future.

So, thè need for too many variables in practice

to achieve formai sufficiency (thè heart of claim 2)

does not work well as thè basis of a criterion of de-

marcation among thè Sciences. We would have to

know a lot more about thè relation between formai

structure and practical use of theories than is evident

from thè literature on theory structure to make claim

2 work.

Another criterion moves from claim 2’s generic

appeal to knowledge necessary to predict, to a more

specific appeal which Sober identifies (in philosophy

of evolutionary biology) with Morton Beckner

(1959).

3. A theory is historical when it contains at least one

historical concept

Sober suggests that Beckner’s chosen example,

that physiological theory is historical because it con¬

tains concepts of physiological States that are histori¬

cal, such as «hungry», is inapt. Physiologists are

quite comfortable explaining physiological proces-

ses with methods drawn from physics and chemistry

that (by assumption) do not require any historical

concepts. To understand «hungry» as a historical

concept one would therefore be thrown back on a

version of claim 2, that a theory contains historical

concepts because they are thè means used to refer

to thè past, which is necessary to predict thè future.

But Sober offers another, better example: «adapta-

tion». The now standard reading of (evolutionary)

adaptation is that it applies only to traits that have

arisen by a «historical process» of naturai selection.

That is to say, present States of adaptedness are out-

comes of naturai selection processes that operated in

thè past.

But Sober rejects claim 3 as well because it implies

that many concepts from physics, e.g. acceleration,

are also historical and therefore that physics is a

historical Science. He further points out that

thè process laws of evolutionary theory, such as

concern thè principle of naturai selection, are ahisto¬

rical in thè sense of claims 2 and 3, so it is hard to see

how appeals to claim 3 can succeed merely by appli¬

cation to concepts regarding thè outcome of such

processes.

Perhaps thè main difficulty with claim 3 is also thè

reason for thè faint hope that it could work. It merely

pushes thè problem of historicality of theories back

to thè problem of historicality of concepts. If a crite¬

rion of thè latter could be produced independently of

any assumed meaning of thè historicality of theories,

then claim 3 might succeed. Sober’s argument

against claim 3 simply shows that we have not suc-

ceeded in an independent characterization, not that

claim 3 fails. Appeal to thè historicality of «adapta¬

tion» as a concept depends on thè assumption that

thè process of naturai selection is historical, perhaps

just in virtue of being a process. While that may in

fact be true, it fails as a demarcation criterion since it

throws us back on claim 2 or claim 1, both of which

fail, as we have seen. Unfortunately, I have no fur¬

ther insight on how to characterize «historical con¬

cept» independently, so I reject claim 3 as unpromis-

ing but not conclusively false.

Finally, we reach Sober’s preferred criterion:

64

JAMES R. GRIESEMER

4. A theory is historical if it «has a built-in temporal

asymmetry. The theory enshrines a difference bet-

ween thè direction from present to future and thè

direction from present to past»

Sober recognizes that this claim fails to demarcate

evolutionary theory from all of physics. Thermo-

dynamics turns out to be a historical Science accord-

ing to claim 4 through its formulation of thè princi-

ple of entropy. To suggest that this demarcation

failure is acceptable, Sober notes thè deep parallel

between evolutionary theory and thermodynamics

that R. A. Fisher developed in his fundamental

theorem of naturai selection. Fisher (1930) argued

that selection causes an increase in mean popula-

tion fitness in proportion to thè additive genetic va-

riance in fitness. Sober, of course, must take care of

thè objection than mean population fitness need

not be maximized by naturai selection (e.g., if it is

frequency-dependent). Professor Scudo (pers.

comm.) points out that Fisher’s fundamental theo¬

rem is not true in generai, but thè point here is

not about its truth, but about thè parallel to prin-

ciples in physics. Since thè same sort of caveat is

true of increase in entropy, these objections do not

undercut thè comparison between biology and

physics. And in accepting claim 4 as adequate,

Sober acknowledges that some parts of physics are

historical.

Once again, a question about practice arises. The

highly mathematized, clearly formulated evolution¬

ary theory of which Sober speaks is tethered at very

few points to data about naturai populations. In fact

it is most successful only in highly constrained

laboratory populations and abstract mathematical

models. True, claim 4 works as a criterion applied to

this idealized, abstracted theory and I am willing to

accept it as such. But it teaches us little about evo¬

lutionary theory or evolutionary Science to cali an

abstract model historical. Moreover, if naturai selec¬

tion in nature is almost always frequency-dependent,

then analysis of thè theory has only a tenuous grip on

thè practices of evolutionary biologists trying to un-

derstand evolution in nature. This not to say that thè

theory is not a triumph, but only that thè worries rai-

sed above are stili in play. Moreover, thè theory is

only remotely connected to thè practice of systemat-

ics, and most definitely not connected to cladistic or

phylogenetic patterns through successful, precise

predictions. So judgment on thè basis of acceptance

of claim 4 that evolution is a historical Science rests

on thè stili unjustified claim that thè mathematical

theory of evolutionary genetics is thè «core» of evo¬

lutionary theory.

Worse stili, as I noted above, it is not clear that

systematics has a centrai theory in thè way that evo¬

lutionary genetics does, though I would certainly

agree with Ghiselin (1969) that Darwin’s theory of

descent with modification and his principle of natu¬

rai selection are core if anything is. My worry here is

with thè concept of «core», not of «theory» — w e

don’t have a thorough understanding of thè relation

between theory and practice to justify thè linkage re-

quired to sustain claim 4 as an analysis of historical

Science. My point is that a demarcation criterion like

claim 4 may never be directly applicable to a Science

like systematics unless its application to thè core

theory helps us interpret systematics practices as

well. Such help may eventually be produced, but thè

indirect application of claim 4 solely through thè rhe-

toric of evolutionary synthesis and core looks rather

dubious.

One thing claim 4 has going for it is a certain simi-

larity to views expressed by Stephen Jay Gould

(Gould, Gilinsky & German 1987). Gould argues,

going back to thè heyday of «nomothetic paleontolo-

gy» and random clade studies by thè «MBL Group»,

that thè data of clade diversity show historical direc-

tionality. Gould et al. argue that clades that origi¬

nate early in thè history of a larger group tend to be

bottom-heavy, i.e. to have more members in thè

fìrst half of their temporal duration than in thè se-

cond half. (Put differently, that their «centers of

gravity» are at less than half their duration, measu-

red by First and last appearance in thè fossil record).

Clades that originate late in thè history of a given

larger group tend to be «neutrally bouyant» or top-

heavy. Thus thè history of a larger group has a

signature in thè statistics of clade shape at any

given time-plane. Thus thè data themselves show

directionality.

If there were a theory of clade diversity that explai-

ned thè phenomenon discussed by Gould et al., then

it would probably be a theory which satisfies claim 4

and would therefore be a historical theory. I do not

think that such a theory currently exists. But more

importantly there is some ambiguity in claim 4. The

fìrst sentence of thè claim requires that «it», thè

theory, has thè built-in tenporal asymmetry. But

since theories are abstract objects (on thè usuai phi-

losopher’s reading, which is tacit in thè covering-law

model of explanation), it is ambiguous to say that thè

theory has a temporal asymmetry built-in. Presum-

ably this is clarified in thè gloss in thè second senten¬

ce: thè theory «enshrines» a difference in two tempo¬

ral directions, i.e. thè theory describes or entails an

asymmetry in nature. But thè second sentence is also

ambiguous. It either means that thè theory refers to a

temporal asymmetry in thè phenomena, or that it

makes some claim or assumption about thè nature of

time itself. If we assume thè former, then claim 4

seems to be in line with thè empirical claim of Gould

et al. The data shows directionality, so a proper theo¬

ry of clade diversity, if we had one, would satisfy

claim 4.

But now we are left with a troubling counterfac-

tual application of claim 4 to a Science in order to

argue that a theory is historical: if thè data of a Scien¬

ce have a built-in temporal asymmetry, and if there

were a proper theory for such data, then thè theory

would be historical. This is clearly inadequate, be-

cause it does not follow from thè temporal asym¬

metry of thè data that every theory of them would

satisfy claim 4, and how are we to distinguisi! coun-

terfactually thè ones that are historical from thè

ones that are not? What pressure is there from

nature on our scientific interests, such that we for¬

mulate a theory historically so as to «mirror» this

aspect of thè phenomena? Mirroring nature is so-

mething scientists may or may not wish to do with

their theories.

In thè light of this lack of a proper theory of clade

diversity, and of a meta-theory sufficient to infer that

a proper theory of clade-diversity would meet claim

4, one might be tempted simply to cut theory out of

thè picture by altering claim 4:

SOME CONCEPTS OF HISTORICAL SCIENCE

65

4*. If thè data have a built-in temporal asymme-

try, then thè Science that includes those data is

historical

But claim 4* is suspect as well. Thus far we have

only seen difficulties in extending criteria of demar-

cation for historical vs. ahistorical theories to Scien¬

ces. By switching to thè data of a Science from thè

nature of a theory, we no longer have conceptual re-

sources enough to judge whether claim 4* is satis-

fied. Why, for example, couldn’t we adopt Sober’s

criticism of claim 1 along with thè theory that time is

asymmetrical to argue that all Sciences of thè physi-

cal world are historical? Then every pair of data

points referring to distinct moments of time will ex-

hibit temporal asymmetry: one datum is earlier than

thè other. We do not require some further «signa¬

ture» in thè data to know that data necessarily exhi-

bit temporal asymmetry of this fundamental sort. In-

deed, thè very idea of data from different moments

in time implies temporal asymmetry. But if we want

to rule out thè temporal asymmetry of time itself as

thè relation through which data are considered to sa-

tisfy 4*, how can a restriction be made? What makes

one asymmetric relation relevant and another not?

What makes a theory or a Science historical, in short,

is not thè nature of thè data, but what scientists do

with them.

Thus, I conclude that thè four options discussed

by Sober et al. are not satisfactory. Let me add two

more: one that, like thè others, is unsatisfactory on

conceptual grounds but nevertheless interesting

because it results from considerations of problems

fundamental to systematic biology, and another that

does thè work I want it to, though it will probably not

satisfy philosophers as a respectable criterion.

Philip Kitcher (1989) revisits thè question whether

species are individuals or classes (sets) from thè

point of view of formai logicai issues. Kitcher offers a

criticism of thè species-as-individuals view that leads

to an interesting possibility for a criterion of what

makes a Science historical. Kitcher does not develop

such a criterion per se, nor is that an aim of his essay

and critique of thè Ghiselin-Hull species-as-indivi¬

duals theory.

In criticizing thè species-as-individuals theory,

Kitcher tries to disentangle what he sees as a confu-

sed and misleading claim, that it is a thesis about thè

ontology of species, from what he sees as an interest¬

ing thesis about what makes individuals historical.

Since species-as-individuals theory entails that spe¬

cies are historical individuals, Kitcher expects it to

formulate a position on historicality. I will use Kit-

cher’s formulation of such a position below to state a

criterion of historicality for a Science.

Kitcher introduces a concept he calls «historical

connectedness» in order to say what he thinks is at

thè heart of thè answer to thè interesting problem

posed by thè Ghiselin-Hull theory. He offers two for-

mulations, one in thè idiom of mereology (thè logie

of parts and wholes or individuals), and one in thè

idiom of set theory (thè logie of members and sets).

Kitches draws on two alternative logicai schemes be¬

cause he thinks that Hull’s arguments do not suffice

to show that species are not sets. This does not mean

that Kitcher has shown that species are sets, but only

that he thinks Hull has not shown that they are not.

By offering a formulation in terms of mereology and

one in terms of set theory — logicai schemes with dif¬

ferent ontological assumptions — Kitcher maintains

neutrality on whether thè Ghiselin-Hull theory is

about thè ontology of species.

The mereological version of Kitcher’s criterion of

historical connectedness is as follows:

. . . we conceive of an individuai with organisms as parts to be his-

torically connected just in case for any organismal parts x and y

such that x preceeds y and for any organism z, if z belongs to a

population that descended from a population containing x and

that is ancestral to a population containing y then z is also part of

thè same individuai as x and y. (Kitcher 1989, 187).

The set-theoretical version is:

A set of organisms is historically connected just in case it satisfies

thè following condition: for any organisms x, y and z, if x and y

are in thè set and if z belongs to a population that is descendant

from a population which has x as a member and that is ancestral

to a population that has y as a member then z is in thè set. (ibid.).

Kitcher goes on to develop an interesting argu-

ment for thè claim that if thè Ghiselin-Hull theory

that species are historical individuals means that spe¬

cies are historically connected entities, then their

theory is incompatible with Mayr’s biological species

concept. Kitcher argues that thè biological species

concept is compatible with species not being histori¬

cally connected, and since his formulation of thè

Ghiselin-Hull theory implies that species must be

historically connected, there is a contradiction.

While I do not think thè argument is sound, an

interesting criterion for what makes a theory or a

Science historical can be constructed using Kitcher’s

criterion of historical connectedness:

5a. An entity is historical if and only if it is histori¬

cally connected

5b. A theory (or Science) is historical if at leastsome

of its objects are historical entities

Unfortunately, there is an equivocation on thè

meaning of thè term «population» at a criticai point

in Kitcher’s argument that Ghiselin-Hull theory, on

Kitcher’s interpretation in terms of his criterion, is

incompatible with thè biological species concept.

This equivocation raises doubts about thè generai

utility of historical connectedness as a criterion of

historicality. The source of thè trouble is that noth-

ing follows from Kitcher’s analysis about thè relation

between species and their members or parts without

some further specifìcation of thè relation between

populations and historical individuals. Kitcher has

chased thè problem to thè level of populations, but

has not sufficiently analyzed thè concept of biologi¬

cal population for his argument to go through.

Because of this problem, I do not think 5a + 5b is a

successful criterion of what makes a theory or Scien¬

ce historical. But I have no generai argument to show

that a definition of historical connectedness cannot

serve as thè basis for a concept of historical entity.

I have only claimed that without clarification of thè

concept «population» and thè relation between

population and species, Kitcher’s use of thè criterion

fails as a criticism of Ghiselin-Hull theory. Extension

of 5a + 5b to thè concept of population may result in

an adequate criterion. This would address thè goal of

proponents of claim 4 by identifying thè source of

historicality of a theory or Science with properties of

66

JAMES R. GRIESEMER

thè objects of study rather than with thè methods or

concepts, but by identifying a particular property

other than temporal relation per se and thereby solv-

ing thè problem with claim 4 raised above. But abs-

ent thè extension, there is much cause for skepti-

cism: thè species problem is hard enough, and now

thè equally hard problem of population has been

added to thè task.

Where do these considerations leave us? The first

four criteria are out and number 5 is open to doubt.

Good-faith attempts to ground historicality in refe-

rence to multiple points of time, to prediction, and to

directionality in thè data have failed and thè last,

connectedness in time, has failed to establish tempo¬

ral order in thè phenomena definitively. I am led

to try another avenue, one that ignores theory alto-

gether and focuses on thè historicality of a Science.

Before characterizing historical Science, I must in¬

troduce thè concept of narrative sentence (Danto,

1985, eh. 8). To thè extent that thè analytical philoso-

phy of history illuminates thè generai problem of

what constitutes history, it will illuminate thè con¬

cept of historical Science. Danto’s view of thè role of

narrative sentences in understanding history is signi-

fìcant for my argument: «My thesis is that narrative

sentences are so peculiarly related to our concept of

history that analysis of them must indicate what

some of thè main features of that concept are»

(Danto 1985, 143).

My analysis of historical Science is framed in terms

of thè concept of narrative sentences and a pragmatic

criterion related to their presence in a Science. As

such, thè defmition of narrative sentence becomes

part of thè criterion of historicality of a Science.

6a. A sentence is narrative if it refers to at least two

time-separated events, but only describes, i.e. is only

about, thè earliest event to which it refers

Narrative sentences have a «teleological» charac-

ter in that they refer to events in thè future of a given

event in order to describe and interpret thè signifi-

cance of thè event. The sentence, «Malthus develo-

ped thè basis for Darwinian evolutionary theory in

An Essay on thè Principle of Population », is narrative.

It is about Malthus at thè time of writing of this essay

(published in 1978), but it refers in addition to some-

thing in thè future of that event, Darwin’s working

out (in thè 1830s) and publishing (in thè 1850s) his

theory of evolution by naturai selection. The sentence

describes Malthus in terms that lend significance to

his writing due to events of which Malthus could

not have known at thè time. It selects his writing as

signifìcant among contemporaneous events in virtue

of what happened later.

An important contrast between narrative and non¬

narrative sentences in biology stems from a gramma-

tical difference between thè relation «ancestor-of»

and thè relation «descendant-of». The sentence «a is

an ancestor of b» refers to two objects, a and b. b is in

thè future of a, and a is thè subject of thè sentence,

which is therefore narrative. In contrast, thè senten¬

ce, «b is thè descendant of a » refers to something in

thè past of its subject and is therefore non-narrative.

The grammar of narrative sentences of thè kinds

found in systematic biology has not been well explo-

red from a logicai point of view, and I only mention it

here to indicate problems and subtleties that await,

especially for concepts like Kitcher’s historical con¬

nectedness that refer to genealogical relations.

With Danto’s concept of narrative sentence in

mind, I can now define «historical Science».

6b. A Science is historical to thè extent that is admits

narrative sentences as contributing to understanding

Unlike claims 1 — 5, claim 6 (6a + 6b) differentiates

explicitly between a historical Science and a histori¬

cal theory. This results from thè concept of admis-

sion indicated in claim 6b. I have not specifìed what

it means precisely for a sentence to be admitted into

a Science and I reject thè idealized characterization

of Science as a «body» of knowledge and theory as a

set of statements or sentences, but there is some

sense in which thè sentences circulating orally and in

writing — among a community of scientists — are ad¬

mitted into thè Science. I want also to distinguish

between admission into a Science and admission into

theory (minimally because contradictory sentences

may plausibly be admitted, consciously, into thè for-

mer and not thè latter). To be sure, there may be dis¬

agreement as to which sentences are admissible or

have been admitted, and even lack of cooperation in

thè admission process, but admitted sentences are

nevertheless «in play».

If one wants to characterize what it means for a

theory to be historical, it is a virtue to make this para-

sitic on thè concepts of historical Science. Theory, at

least in thè grand sense implied by most philosophi-

cal work, is not necessarily thè heart of a Science and

I do not see any reason to think thè historicality of a

Science is any more dependent on thè historicality of

a theory than on thè historicality of its data. So I cha¬

racterize a theory as historical when it (however

characterized) is put to use by scientists in a given

Science toward narrative purposes. Thus I think that

evolutionary theory is historical because (some) evo¬

lutionary scientists use it for narrative purposes. I do

not demand that, for example, population genetics

theory be put to narrative use even if one accepts that

theory as part of evolutionary theory because I do

not demand that a Science hang together very well or

for very long.

To be too rigorous about such defmitions is to do

violence to thè fragility of Science as a process. If

someone objects that then every theory is historical

or not depending on usage and that we therefore

cannot teli whether a theory is historical by inspect-

ing its structure, I would reply that this is no objec-

tion unless thè reasons to cali for this independent

means of assessment of theories are made clear. If

someone prefers to claim that I have only defìned

thè historical use of theories and not historical theo¬

ries, I would not object: whether a theory turns out to

be historical or not is not an important question.

I want also to make one further comment about

thè analysis itself concerning thè role of narrative

sentences in characterizing historicality. One reason

I have chosen this route is to avoid some problems

with thinking of narrative «linearly», that is, with in-

terpreting narrative as stating single, unbranching

causai sequences of events from A to B to C, etc.

Robert O’Hara wams about producing linear evolu¬

tionary narratives. He points out that thè subjects of

SOME CONCEPTS OF HISTORICAL SCIENCE

67

systematics are clades, and these «branched pieces of

thè evolutionary tree» lack some of thè key proper-

ties of thè sort of individuals that typically serve as

«centrai subjects» in human narratives (O’Hara 1988,

152). Terminal taxa in a tree do not have continuity

one with another, they are linked only by common

ancestry. They also do not always have distinct end-

ings in time, a property that O’Hara calls «closure».

He observes that recognition of paraphyletic taxa is a

means of imposing an artifìcial closure on an evolu¬

tionary group to «minimize thè cladistic aspect of

evolution and maximize thè linear aspect (or rather

create an imaginary linear aspect)» (ibid.).

Admission of narrative sentences as a criterion of

historicality is intended not to prejudice thè linearity

or non-linearity of narrative. Since 6a only requires

that a narrative sentence refer to at least two differ-

ent times and that it be about only thè earliest time

to which it refers, nothing is implied about whether

narratives must be linear or not. Whether a Science,

like systematics, is historical, is thus a distinct question

from whether its narratives are or should be linear.

O’Hara’s «tree thinking» is compatible with a variety of

conceptions of historicality and narrative structure.

This is important because it is open to question

whether O’Hara’s distinction between evolutionary

history and evolutionary chronicle can be sustained.

Danto characterizes chronicle as distinct from his¬

tory as:

...just an account of what happened, and nothing more than

that . . . [T]he very best kind of chronicle [which gives «all thè

details»] would stili not quite be history in thè proper sense . . .

Proper history regards chronicles as preparatory exercises. Its

own task is rather concerned with assigning some meaning to,

or discerning some meaning in, thè facts allegedly reported by

chronicles. (1985, 116).

Following Danto, O’Hara claims that «Systematics

is thè discipline which estimates thè evolutionary

chronicle» (O’Hara 1988, 144; emphasis his). And evo¬

lutionary chronicle is thè description of a series of

events without accompanying «causai statements,

explanations, or interpretations» (ibid.). I can accept,

as does O’Hara, thè distinction between history and

chronicle as it is developed in thè philosophy of his¬

tory, but if this distinction is pressed into systematics

along certain lines it will, I think, run into problems.

If O’Hara’s view is that cladistic analysis is to

phylogeny reconstruction as chronicle is to (narra¬

tive) history, then I disagree with his analysis on two

scores. First, I think thè practices of systematists teli

against a distinction O’Hara tries to draw between

human historians and systematists. He writes,

In contrast to thè historian, thè systematist performing a cladistic

analysis is trying to use all available evidence to estimate thè po-

sition of as many evolutionary events as possible; he is not trying

to construct a narrative account of a selected set of those events.

(146-47).

Sober (1988), following arguments by Felsenstein,

suggests that thè question of available evidence is a

complex one in systematics. The traditional view of

advocates of parsimony methods for cladistic analy¬

sis has been that only shared derived characters (syn-

apomorphies) provide evidence of cladistic relation-

ships. But Sober and Felsenstein have both argued

through consideration of maximum likelihood me¬

thods that there are evolutionary circumstances in

which shared ancestral characters (symplesiomor-

phies) can also provide cladistic evidence. It is irre-

levant here to try to decide which view of cladistic

methodology is correct. My point is simply that what

counts as available evidence is a negotiable matter in

systematics. At thè very least, choice of parsimony as

a method does not lead to interpretation-free des-

criptions, so cladistic analysis produces something

more theoretically charged than chronicle.

Second, while I agree that cladistic analysis aims at

something prior to evolutionary narrative in thè way

that chronicle preceeds history, I think it is false to

say that in performing cladistic analysis a systematist

avoids thè kind of selections among events that are

essential to historical narrative. The «out-group me¬

thod» for determining character polarity, for exam-

ple, involves a selection from among a number of

possibilities. But thè selection process here is buried

in thè «craft work» of systematists that is not usually

considered part of thè cladistic analysis per se, e.g. in

knowing or having hunches about what would make

suitable out-groups, which is tantemount to a judg-

ment of meaning or historical signifìcance. Professor

Urbani makes thè even stronger claim that thè

simple choice of a statistical computer package per¬

forming maximum likelihood or parsimony methods

is a declaration of faith in a given school of thought

and that practicing systematists are well aware of

such craft commitments (pers. comm.). My argu-

ment is with thè artifìcial separation of craft work

from high theory in thè philosophical analysis of sys-

tematic practice. Moreover, Sober and Felsenstein

have both vigorously argued that in order to do cla¬

distic analysis at all, some model of character evolu¬

tion must at least be tacitly assumed (Sober 1988,

eh. 6). This imposes interpretive constraints and se¬

lection of data, based on events in thè future of thè

branching sequences that cladistic analysis seeks to

«estimate». For example, in assuming a neutral rate

of molecular substitution, a model of character evo¬

lution refers to a process spanning thè whole tempo-

ral duration of thè clade being analyzed.

For these reasons, I think it will be difficult to pur-

sue «a new philosophy of evolutionary biology», as

O’Hara desires, «which reflects thè discipline’s histo¬

rical nature», unless thè practices of thè discipline

are articulated along with thè centrai theoretical con-

struets that are usually identified with thè core or es-

sence of a discipline. I suspect that O’Hara agrees

with this conclusion: he has begun thè critique of

such disciplinary practices (see his 1990, 1992), focus-

ing on thè character of evolutionary narratives (see

also Landau 1984). In systematics there is a tendency

to equate cladistic analysis with only thè final step of

running a computer program on a data set to produce

trees. This is misleading about cladistic practice be¬

cause most of thè selection and a substantial amount

of interpretation are implicit in thè so-called «metho-

dological» choices already made before a particular

computer package is run. Neither do such methods

thereby constitute a theory. It is therefore desirable to

take as primary thè historicality of a Science so as to

include all of thè discursive practices besides those no-

minally connected with theory-structure, and to charac-

terize thè historicality of a scientifìc theory derivately.

Claim 6 entails nothing that compels evolutionary

biologists to treat their Science historically and noth¬

ing that precludes physicists from doing so. Histori¬

cality is a property that a Science has in virtue of thè

pragmatic commitments that scientists make in

68

JAMES R. GRIESEMER

doing Science. As such, it has no logicai or physical

necessity. Indeed, it doesn’t even have social or cul¬

tural necessity: it is possible to practice a historical

Science ahistorically and an ahistorical Science histo-

rically. Pragmatic commitments are negotiated parts

of thè social order of scientific practice, not frag-

ments of epistemology or metaphysics.

To put this point in terms of thè foregoing review

of various attempted analyses of historicality, one

need not refer to multiple points in time in order to

describe a given moment of time. Fading to do so,

however, leads to singularly uninteresting Science, as

thè logicai positivists showed with their protocol sen-

tences as exemplary of ideal Science («Otto senses a

red patch in thè upper left quadrant of his visual fìeld at

4:05 pm, Thursday»). Their thought experiment in ideal

Science showed that not even thè level of commitment

to temporality required by claim 1 is logically or episte-

mologically necessary, but such commitments are prag-

matically necessary if Science is to be interesting.

One need not invoke thè past in order to predict

thè future either. Claim 2 says nothing about how

adequacy conditions for successful prediction are ar-

ranged in conjunction with conditions for construct-

/'«gpredictions, and even Hempel’s symmetry thesis,

which brings prediction under thè same umbrella as

explanation, is mute on this. So, there is a wide fìeld

for deciding to refer to thè past in formulating predic-

tions and their acceptance. Perhaps some generai

regularities will be discovered in thè prediction-

forming, -testing, and -judging habits of scientists,

but I doubt it.

One need not invoke historical concepts in order

to formulate scientific theories, either. In thè discus-

sion of thè concept of adaptation above, thè claim

that this concept is historical was discusseci. But even

if accepted at face value, it is stili open to biologists

to operate without thè concept. Using adaptation as

an evolutionary concept requires commitment, one

that neutral mutationists, for example, have tried at

times to do without. It is certainly open to evolution¬

ary biologists to change thè scope of their Science to

exclude, as physicists have done, phenomena that

seem to require concepts that do not meet their me-

thodological «standard of taste».

One need not have intrinsic directionality «in thè

data» in order to commit to interpreting data histori-

cally. Temporal asymmetry is automatic in data, as I

suggested, just in virtue of thè fact that time itself has a

direction and events and objects are located in time.

Finally, one need not have historically connected

objects as subjects for a Science to be historical. If

Kitcher is right that thè biological species concept al-

lows species to be historically unconnected, then in

so far as evolution was a historical Science when thè

biological species concept was uncontested, it does

not need historically connected objects. On thè other

hand, if it turns out that Kitcher is wrong and thè

biological species concept implies that species are

historically connected, it is stili plausible to think

that evolutionists could proceed without their Scien¬

ce being historical. They could, for example, embra-

ce with enthusiasm what Dobzhansky reluctantly ac¬

cepted as a working hypothesis in 1937: evolution is

change in gene frequency. This commitment to thè

much maligned bean-bag genetical view of evolu¬

tion, coupled with thè view expressed in criticism of

claim 2, that population genetics is just one more dy-

namical theory (and not thereby historical), would

suffìce to allow evolution to be practiced as an ahis¬

torical Science.

I doubt that my pragmatic criterion 6 will be

warmly received. Certainly my criticisms of thè other

criteria do not constitute a rigorous argument in

favor of my preferred criterion, though others re-

flecting on systematics have championed a pragmatic

criterion of explanation, if not of historicality per se

(see Ghiselin 1969, p. 29). Claim 6 seems to admit a

rather literary quality of historical Science that many

have been at pains to avoid, for one or more of thè

reasons I discussed. But one virtue of thè pragmatic

criterion is that it highlights something thè others

have in common: they all try to fìnd properties that

make a theory or Science necessarily historical. While

I do think that thè Sciences can be demarcated, one

from another and from other parts of society and cul¬

ture, I do not think that seeking a necessary condi-

tion for a distinction among Sciences as thè first four

criteria do is thè right approach. The pragmatic cri¬

terion focuses attention squarely on two things: thè

social process of commitment and thè nature of

historical narratives. Many of thè reasons for label-

ling a Science (or theory) historical can be addressed

by investigating a centrai feature of narratives: they

assume a periodization of history which serves as a

theoretical model in narrative construction. It is this

aspect construction of theoretical models, that puts

historical Science on an equal footing with ahistorical

Science and defeats thè hierarchical view of scientific

authority. But naturai historians have not articulated

thè view that their Science is fully theoretical (Grie-

semer 1990). Analysis of thè structure of theoretical

historical models would go far toward answering thè

critics (Griesemer ms).

Acknowledgments — I thank thè conference orga-

nizers for their invitation to participate in thè work¬

shop; thè Museo Civico di Storia Naturale di Milano

for its hospitality; Shahid Amin, John Damuth,

Elihu Gerson, and Michael Ghiselin for helpful

discussion; and thè Wissenschaftskolleg zu Berlin

for a fellowship in 1992-93 that supported this re-

search. I am grateful to Professor Scudo for pressing

his objections and criticisms with vigor.

BIBLIOGRAPHY

Beckner M., 1959 - The Biological Way of Thought. University of

California, Berkeley.

Beer G., 1985 - Darwin’s reading and thè fictions of develop-

ment. In: D. Kohn (ed.) - The Darwinian Heritage. Princeton

University, Princeton, 543-588.

Benjamin W., 1968 - Illuminations. Hartcourt, Brace & World,

New York, quotation at 265.

Cartwright N., 1983 - How thè Laws of Physics Lie. Oxford

University, New York.

Danto A. C., 1985 - Narration and Knowledge. Columbia Univer¬

sity, New York, including thè integrai text of Analytical Phi-

losophy of History, 1968.

Ereshefsky M., 1992 - The historical nature of evolution¬

ary theory. In M. H. Nitecki and D. V. Nitecki (eds.) - His¬

tory and Evolution. State University of New York, Albany:

81-99.

Fisher R. A., 1930 - The genetical Theory of Naturai Selection.

Reprinted 1958. Dover, New York.

SOME CONCEPTS OF HISTORICAL SCIENCE

69

Flew A., 1959 - The structure of Darwinism. New Biology, 28:

25-44.

Ghiselin M., 1969 - The Triumph of thè Darwinian Method.

University of California, Berkeley.

Ghiselin M., 1974 - A radiai solution to thè species problem.

Systematic Zoology, 23: 536-44.

Goudge T. A., 1958 - Causai explanations in naturai history.

British Journal for thè Philosophy of Science, 9: 194-202.

Gould S. J., 1986 - Evolution and thè triumph of homology, or

why history matters. American Scientist, 74: 60-69.

Gould S. J., 1989 - Wonderful Life, The Burgess Shale and thè

Nature of History. W. W. Norton, New York.

Gould S. J., Gilinsky N. L. & German R. Z., 1987 - Asymmetry

of lineages and thè direction of evolutionary time. Science,

236: 1437-1441.

Griesemer J. R., 1990 - Modeling in thè museum: on thè role of

models in thè work of Joseph Grinnell. Biology & Philosophy,

5: 3-36.

Griesemer J. R. - Periodization and Models in historical biology.

(Unpublished ms.).

Hempel C. G., 1942 - The function of generai laws in history.

Journal of Philosophy, 39: 35-48.

Hempel C. G., 1965 - Aspects of Scientific Explanation and Other

Essays in thè Philosophy of Science. The Free Press, New

York.

Hempel C. G. and Oppenheim P., 1948 - Studies in thè logie of

explanation. Philosophy of Science, 15: 135-75.

Hull D. L., 1974 - The Philosophy of Biology. Englewood Cliffs,

NJ., Prentice-Hall.

Hull D. L., 1980 - Individuality and selection. Annual Review of

Ecology and Systematics, 11: 311-32.

Hull D. L., 1992 - The particular-circumstance model of scien¬

tific explanation. In: M. H. Nitecki and D. V. Nitecki (eds.).

History and Evolution. State University ofNew York, Albany:

69-80.

Kitcher P., 1989 - Some puzzles about species. In: M. Ruse (ed.).

What thè Philosophy of Biology Is: Essays Dedicated to

David Hull. Dordrecht, KluwerAcademic; Nijhoff Interna¬

tional Philosophy Series, 32: 183-208.

Landau M., 1984 - Human evolution as narrative. American

Scientist, 72: 262-268.

Laudan R., 1992 - What’s so special about thè past? In: M. H. Ni¬

tecki and D. V. Nitecki (eds.). History and Evolution. Alba¬

ny, State University ofNew York, 55-67.

Levine A. and Sober E., 1985 - What’s historical about historical

materialism? Journal of Philosophy, 82: 304-26.

Lewontin R. C., 1974 - The Genetic Basis of Evolutionary Chan-

ge. Columbia, New York.

Lloyd E. A., 1988 - The Structure and Confirmation of Evolu¬

tionary Theory. Greenwood Westport, CT.

Nagel E., 1961 - The structure of Science: Problems in thè Logic of

Scientific Explanation. Harcourt, Brace & World, New York.

O’Hara R. J., 1988 - Homage to Clio, or, toward an historical phi¬

losophy for evolutionary biology. Systematic Zoology, 37:

142-155.

O’Hara R. J., 1990 - Representations of thè naturai System in thè

nineteenth century. Biology & Philosophy, 6: 255-274.

O’Hara R. J., 1992 - Telling thè tree: narrative representation and

thè study of evolutionary history. Biology & Philosophy, 7:

135-160.

Popper K. R., 1957 - The Poverty of Historicism. Routledge &

Kegan Paul, London.

Popper K. R., 1972 - Objective Knowledge, An Evolutionary

Approach. Oxford University, Oxford.

Popper K. R., 1978 - Naturai selection and thè emergence of

mind. Dialectica, 32: 339-99.

Richards R. J., 1992 - The structure of narrative explanation in

history and biology. In: M. H. Nitecki and D. V. Nitecki

(eds.). History and Evolution. State University of New York,

Albany: 19-53.

Russell B., 1913 - On thè notion of cause. Proceedings of thè Aris-

totelian Society, 13: 1-26.

Salmon W. C., 1989 - Four decades of scientific explanation. In:

P. Kitcher and W. C. Salmon (eds.). Scientific Explanation.

Minnesota Studies in thè Philosophy of Science. University

al Minnesota, Minneapolis, XIII: 3-219.

Smart J., 1963 - Philosophy and Scientific realism. Routledge &

Kegan Paul, London.

Sober E., 1988 - Reconstructing thè Past: Parsimony, Evolution

and Inference. MIT, Cambridge.

Van Fraassen B., 1980 - The Scientific Image. Princeton Universi¬

ty, Princeton.

Williams M., 1970 - Deducing thè consequences of evolution:

a mathematical model. Journal of Theoretical Biology, 29:

343-85.

Wimsatt W., 1980 - Reductionistic research strategies and their

biases in thè units of selection controversy. In: T. Nickels

(ed.), Scientific Discovery: Case Studies. D. Reidei, Dor¬

drecht: 213-259.

Wright E. O., Levine A. & Sober E., 1992 - Reconstructing Mar-

xism: Essays on Explanation and thè Theory of History.

Verso, London.

James R. Griesemer: Wissenschaftskolleg zu Berlin (Institute for Advanced Study Berlin) and University of California,

Department of Philosophy, Davis, CA 95616-8673, U.S.A.

Systematic Biology as an Historical Science

Memorie della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano

Volume XXVII - Fascicolo I - 1996

.

Alessandro Minelli

Some thought on homology

150 years after Owen’s definition

Abstract - During thè last two centuries, several homology concepts, most often implicit but sometimes explicit and

theoretically belaboured, have supported thè most diverse research programmes, especially in comparative morphology,

systematics and developmental biology. There seems to be no reason for restricting today thè meaning and thè uses of this

term, e.g. only to historical, rather than biological, homology. These different traditional notions may be regarded as facets

of a comprehensive notion of homology, with a major common background in thè commonality of information lying

behind thè objects under comparison, but without any place for archetypes. The importance is stressed of always iden-

tifying thè level(s) of description (hence, thè type of homology) one is considering in a given study. The dangers of

arbitrary atomistic descriptions is underlined. In a ‘combinatorial’ model of homology, a special, independent status is

acknowledged to positional homology, as distinct from special homology: this point is supported by recent advances in

molecular genetics.

How many homology concepts?

A homologue, wrote Owen (1843:374) in a well

known passage, is «thè same organ under every va-

riety of form and function».

Owen was thè first to systematically use thè terms

«homologue» (or «homology») and «analogue» (or

«analogy») in a sense approximately equivalent to thè

sense (or, better, senses) in which we stili use them.

Things were different before, as one easily perceives,

for instance, when studying Geoffroy Saint-Hilaire’s

«théorie des analogues» (e.g., Geoffroy Saint-Hilaire,

1807, 1818, 1830) where what is developed is a concept

akin Owen’s homology, rather than Owen’s analogy.

There is no question as to thè idealistic rationale

of Owen’s homology, but things are not simply set by

stating, as seems to be implicit within some circles,

that to implement Geoffroy’s theory or Owen’s defi¬

nition all biology needed was simply thè advent of

evolutionary thinking, or thè reformulation of histo¬

rical homology concepts in terms of plesiomorphy

and apomorphy (Hennig, 1950, 1966) or even identi-

fying tout court historical homology with synapomor-

phy (Patterson, 1982).

But let me start a little before Owen, with a senten-

ce typical of thè best French morphology of thè early

nineteenth century.

According to Serres (1827:53), thè great discovery

of comparative anatomy had been «that those which

are apparently thè least similar one to thè other are,

however, fundamentally similar, and that, within thè

single individuai as well as among thè whole diversi-

ty of living beings, nature seems to have impressed

two characters, thè one perfectly compatible with thè

other, i.e. constancy within thè type and diversity in

thè modifìcations» (my transl.).

This passage clearly sets thè scope for a multidi-

mensional research programme in comparative mor¬

phology (Minelli, 1995). A broader scope than thè

cross-specific comparative work we now understand,

ever since Darwin and Haeckel, as phylogenetics.

That means that thè historical (genealogical) per-

spective, although prominent in thè current agenda

of comparative biology, does not exhaust thè scope

of this Science. In other terms, equating homology

with synapomorphy means reducing comparative

biology to phylogenetics, and nothing else. We could

also remark, a bit more fastidiously, that terms like

«apomorphy», or «plesiomorphy», strictly refer to

morphological or anatomical features, only by me-

thapor being often extended to functional, behaviou-

ral, ecological or biogeographic ones. This point was

aptly made by Tuomikoski (1967), when suggesting

thè use of thè more comprehensive (but never used)

terms «apotypy» and «plesiotypy».

If we look back at thè history of homology re¬

search, we easily perceive that under this same term

of homology several different traditions developed,

with fluctuating success, ande several of them are

stili alive with us.

There seem to be several different ways of classifying

these traditions, or thè related homology concepts. For

istance, a distinction between transformational and

taxic homology has been widely employed, especially

by cladists (e.g., Patterson, Rieppel, Cracraft, Eldredge,

Panchen). This distinction somehow parallels but

does not strictly identify itself with Wagner’s (1989a)

distinction between biological and historical homo¬

logy concepts.

«Biological homology» rests on thè identication of

correspondance between biological properties, or

processes, underlying thè features under compari¬

son, without any reference to genealogical relation-

ships, or, more generally, to thè temporal dimension

at thè geological time scale; thè opposite holds for

thè historical homology concepts.

Wagner (1989a) regards these biological concepts

of homology, with their reference to biological

mechanisms rather than to genealogical relation-

ships, as more inclusive than thè historical ones. I

would rather regard them as complementary and

worthy of inclusion in a broader construed notion of

homology.

Much of thè trouble with homology, especially in

thè recent literature, has to do with quite opposite

attitudes at this starting point: whether, I mean,

72

ALESSANDRO MINELLI

thè only possible meanings of homology have to be

searched for in a historical perspective, or, on thè

contrary, there is stili also a scope, even in a post-

Darwinian era, for non-historical, but nonetheless

meaningful, concepts of homology.

I do not intend to approach here this question in a

philological vein, i.e. by tracing, work after work, thè

origin and thè fate of individuai terms, like homolo¬

gy, homonomy, homodynamy etc., in order to apply

some kind of priority rule, as does, for instance, thè

International Code of Zoological Nomenclature for

thè scientific names of animai species. I am well

aware that my concept of homology, in so far as it re-

ceives thè legacy of different research traditions, is

perhaps too diffuse to be adequately covered by a

single, universal term, but I feel that, at present, con¬

cepts and corresponding terms may profìt from a glo-

bal discussion within a broader context, before risk-

ing a recrystallization under old or new wordings. A

similar attitude towards homology has been defend-

ed by Ghiselin (1976) and Haszprunar (1992), with

whom I am largely in agreement.

Nor shall I reiterate here thè arguments developed

elsewhere (Minelli & Peruffo, 1991; Minelli, 1992;

also Ghiselin, 1976; Haszprunar, 1992, and others) as

to thè opportunity of keeping within one compre-

hensive concept of homology both inter- and intrain-

dividual relationships, as those traditionally labelled

as special homology and serial homology. Rather, I

shall examine in some detail a few premises, and a

few consequences, of such a catholic approach.

Due to thè multidimensionality of comparative

biology and to thè lack of congruence between

thè different aspects of ‘sameness’ (Wagner, 1994),

a prerequisite for any non trivial use of homology

will always be a clear identification of thè subset of

possible homology components (e.g., positional

homology; or historical homology) we are dealing

with in a given study.

Inadvertently skipping from one kind of compari-

son to another leads all too easily to dangerous situa-

tions. A serious difficulty is stili very well entrenched

in thè literature dealing with thè old issue of ontoge-

ny vs. phylogeny.

From a phylogenetic point of view, one possible

way to look at evolution is to regard it as a history

of changes of ontogenetic programmes. Accordingly,

thè topology of these changes across geological time

is nothing but thè topology of thè phylogenetic tree.

But many evolutionary changes involve hetero-

chronies, or other modifications of thè developmen-

tal schedules, such as to limit thè applicability of

Nelson’s (1978) reformulation of thè biogenetic law.

According to Nelson (1978:327), «given an onto¬

genetic character transformation, from a character

observed to be more generai to a character observed

to be less generai, thè more generai character is pri¬

mitive and thè less generai advanced. «But this is

right thè starting point for Patterson’s (1983) identifì-

cation of ontogeny and phylogeny. I fear that both

Nelson (1978) and Patterson (1983) have fallen vic-

tims of Zeno’s paradox. Achilles will never reach

their turtles, because Zeno, Nelson and Patterson

have limited a priori thè context (a temporal frame-

work in Zeno, a relational one for pattern cladists)

where their game has to be played. The world, howe¬

ver, is wider. Nelson’s and Patterson’s too selective

principles work well, perhaps, but only within thè li-

mits set by a strict pattern cladistic approach, where

homology cannot be other than synapomorphy, as

verified through thè three classic tests of Patterson

(1982).

The dangers inherent in this pattern cladistic ap¬

proach are seldom so evident as in thè following sta¬

tement one can read in Alee Panchen’s (1992) book

on «Classifìcation, Evolution, and thè Nature of Bio¬

logy». We read there, on p. 5, that «If thè pattern of

classifìcation is logically prior to phylogeny [a firm

point, in pattern cladists’ view], thè characters on

which it is based should have logicai priority over thè

pattern. There should therefore be a Naturai Hierar-

chy of characters, whose similarity in all thè mem-

bers of a taxon is recognized as homology».

In spite of thè use of terms like phylogeny, or evo¬

lution, it is here, rather than in a non-phylogenetic

approach to homology, that I perceive an old-fashio-

ned attitude towards comparative biology. I think

that we do not necessarily (better, not always) need

to find out a priority criterion for characters; but,

whenever we need one, why, if not in an essentialis-

tic framework, are we to look for a logicai, rather

than an historical, criterion?

I do not go further with this argument. Rather, it is

perhaps worthy of careful investigation what happe-

ned to Geoffroy’s analogie , or Owen’s homology,

after thè publication of thè «Origin». Here, however,

I will only offer some suggestions.

On thè one hand, thè well-known idealistic exag-

gerations of thè last century do not seem to be com-

pletely dead. Most people will probably regard as

long extinct that early ninenteenth century tradition

of Urpflanzen which, belabouring Goethe’s morpho-

logical speculations, produced those unbelievable

summaries of possible forms we could only define as

hopeless monsters; see, e.g., Turpin’s (1837) picture

of an hypothetical Urpflanze, recently reproduced by

Màgdefrau (1992).

In thè recent literature, there is stili a place for

‘ground-plans’ (for a reasonable example, see En-

ghoffs (1990) chilognathan millipede) but these ra¬

ther run thè apposite risk, to be too poor in structure

as to correspond to possible living animals: in fact,

they are mainly built on thè basis of a few better

founded synapomorphies of a higher taxon, and

nothing else.

But let me read from thè recent (and otherwise

attractive) book of Nijhout on butterfly wing pat-

terns: «The nymphalid ground pian represents thè

maximal pattern that is found in thè family Nympha-

lidae. However, no species is known that has all thè

elements of thè nymphalid ground pian in its wing

pattern» (Nijhout, 1991:27).

On thè other hand, it is fair to say that such slip-

pings are, overall, rare. Problems with thè tradition

of rational morphology are mostly of thè opposite

nature.

In his «Strategy of Life» (1982), Timothy Lenoir

has argued that thè success of thè research agenda

developed around Darwinian evolutionary theory

caused obfuscation of thè German and French com¬

parative morphology developed between thè last de-

cades of thè eighteenth and thè fìrst decades of thè

nineteenth century. In this vein, one could specifi-

cally argue that one effect of this change of mind was

thè more or less conscious restriction of homology to

an historical framework.

SOME THOUGHT ON HOMOLOGY 150 YEARS AFTER OWEN’S DEFINITION

73

It is also fair to say that, until recently, hardly a

mechanism was available as a possible explanation

for thè structural patterns around which developed

thè speculations of a Vicq d’Azyr, or a Geoffroy

Saint-Hilaire. Things are different today, however,

and that seems to me much of a good reason for re-

surrecting (or, better, translating into more modern

terms, as we will see later) many concepts of thè old

rational morphology.

Wagner (1989a, b; also with reference to de Beer

(1971) and to Roth (1988)) has recently argued that «It

seems implausible that continuity of gene lineages

alone could account for thè homology of morpho-

logical features». More recently, Kauffman (1993)

contends that there is a scope for a non-historical

approach to biological organization. This approach

more or less merges with thè structuralist tradition.

Structuralism and Darwinism have been often re-

garded as unreducible opposites, and a lot of structu-

ralists’ excesses well justify this claim, but things

do not need to be so. In a very important paper of

1987, Wake & Larson have convincingly argued in

favour of a synthesis of structuralism and Darwi¬

nism and I cannot but subscribe to their program.

In this perspective, I believe that a suitable, and

adequately broad concept of homology will play a

non-trivial role.

Units of description

«It would be impossible to understand about what

we are talking, says Riedl (1980:157; my transl.),

whenever our terms were not rooted in homology».

In this vein, it is all but difficult to understand

why, ever since Cuvier, people seem to feel so sure,

when partitioning thè Animai Kingdom into a suit¬

able number of embranchements, or phyla. Less often

consciously than not, zoologists feel free from any

obligation to look for homologies, when taking to-

gether (I do not say «comparing») animals they have

placed in two different phyla. Cross-phylum homo¬

logies are, more or less by definition, doubtful,

uncertain, speculative; something that most good

zoologists feel, or felt, not obliged to follow up. At

least, it was so before thè advent of comparative mo-

lecular biology. An all too easy solution, anyway. Let

us look, for instance, at thè prompt dissolution of

thè traditional phylum Arthropoda in thè hands

of Sidnie Manton, as soon as she found herself in

trouble with things such as thè homology between

thè gnathobasic mandible of chelicerates with thè

tip-working mandible of insects and allies (her Uni-

ramia).

Well, homology serves as a universal foundation

of our scientific discourse. But, to begin with, homo¬

logies between what? In morphology, as in other

Sciences (e.g. in descriptive geology; Laudan, 1992),

oe major problem is thè proper identification of suit¬

able units of description and comparison.

As Eldredge & Cracraft (1980) posed it, every com¬

parison cannot but begin within ‘comparable’ units.

«But what does ‘comparable’ mean? — asked Nelson

& Platnick (1981:151-2) — Are not all things ‘compar¬

ale’? Potentially yes, but actually biologists do not

compare arms with eyeballs or noses (although there

is not rule that biologists may not do so). They com¬

pare, for example, arms of a human, or wings of a

bat, with thè fore legs of a frog or thè pectoral fins of

fìshes. To a biologist, these organs display interest-

ing similarities and differences, interesting perhaps

only because a biologist can generalize about. And

by stating that they are homologous, one means at

least that generai statements can be made about

them».

In other terms, «The significant point is that for

any discussion of homology, homologues must fìrst

be recognized based on similarity. The primacy of si-

milarity over phylogeny puts an onus on morpholo-

gists to be able to apply similarity to identified mor-

phological elements» (Young, 1993:235).

Can we subscribe to Young’s posit? Before an-

swering this question, it is perhaps apt to underline,

how loose is thè current use of thè term «morpholo¬

gy», which is often understood as a plain synonym of

«anatomy», sometimes retained in his originai and

legitimate meaning of study of (abstract) form, and

all too often dangerously employed to mean both of

those things. Now, moving back to thè foundations

of homology, it seems to me that similarity, as such,

can only be thè background of that ‘operational no-

tion of homology’ (i.e., something that actually has

nothing to do with homology proper) such as develo¬

ped within thè domain of phenetic, numerical taxo-

nomy (Sokal and Sneath, 1963; Sneath and Sokal,

1973; cf. also Patterson’s (1982) historical review of

homology concepts). Within an evolutionary con-

text, things go on otherwise.

A good morphologist, to begin with, is well aware

that there are many different possible levels of des¬

cription. Therefore, thè fìrst aspect to care for is to

avoid mixing, in a given comparison, concepts and

terms pertaining to different facets of morphology or

anatomy. In a well-argued analysis of homology pro-

blems in thè study of animai body cavities, for in¬

stance, Remane (1963) distinguished between (a)

descriptive-histological terms such as gymnocoel

and epitheliocoel, (b) ontogenetic terms such as

schizocoel, enterocoel, neocoel, (c) morphological

terms s.str. such as amniotic cavity, and (d) function-

al anatomical terms like haemocoel.

Nevertheless, this is just thè starting point. More

often than not, it is quite difficult to perceive how

traditionally biased are our current circumscriptions

of only apparently trivial terms, like flower and inflo-

rescence in plants or head, thorax and abdomen in

animals.

First, a botanical example. In a conventional her-

maphrodite flower, there is a standard sequence of

whorls: begininng with thè outmost sepals, we usual-

ly find petals, followed by stamens and fìnally car-

pels. In lieu of sepals + petals, there is sometimes a

single kind of external, nonreproductive elements

(tepals); in addition, any one of these whorls may be

missing, but — this is thè main point — their order is

never reversed. At least, botanists do not allow them

to be. However, to thè scorn of typological botanists,

there actually are a few kinds of flowers where thè se¬

quence of whorls is: outer tepals, outer ring of sta-

mes, inner tepals, inner whorl of stamens. When

confronted with such an arrangement, «thè classical

minded phytomorphologist refuses to accept thè

confìguration [..] as representing a flower, but decla-

res it to be an ‘inflorescence’ (more precisely: a pseu-

danthial inflorescence)» (Meeuse, 1986:10). In a

sense, positional constancy has become a kind of de-

74

ALESSANDRO MINELLI

fining property for thè parts of a flower. But, is this

attitude truly justified? I do not think so. The newest

discoveries in developmental genetics of plants have

shown that not just thè shape and thè colour, but

also thè relative position of thè fiorai elements is

under relatively simple genetic control. The fact that

thè usuai order is seldom reversed does not imply

that it cannot sometimes be upset, as in some labora-

tory mutants. Surely no developmental genetist

would surely argue that an Antirrhinum or an Arabi-

dopsis with its petals and stamens in unconventional

sequence is something different from an (admittedly

odd) flower. Interestingly enough, Martinez and

Ramos (1989) have recently discovered a plant species

( Lacandonia schismatica) with literally inverted fiorai

whorls, thè stamens being encircled by thè carpels!

Let me now skip to a zoological example. I do not

intend to discuss here whether there is any sense in

giving thè same name (head) to thè foremost section

of thè body of thè swordfish (a vertebrate), thè

silverfish (an insect) and thè cuttlefìsh (a mollusc),

although this question, to a belated vengeance of

Geoffroy Saint-Hilaire ad his disciples Meyranx and

Laurencet, could be perhaps less crazy than it seems

to be (see later).

Here, however, I wish to point to thè difficulties

in determining what a thorax is in aculeate hyme-

nopterans, where, as it is customary to say, thè fìrst

abdominal segment is incorporateci within thè tho-

racic tagma. Why not to say that thè boundary tho-

rax/abdomen runs here one segment behind its

usuai position in insects?

Again, is it more meaningful to say that thè fìrst

thoracic segment is fused to thè head in woodlice

and allies (Isopoda), or to acknowledge that thè posi¬

tion of thè head/thorax boundary is not universally

thè same within crustaceans?

According to Boxshall & Huys (1992:332), «Tag-

mata separeted by boundaries that lie in different

location cannot be compared. For example, maxillo-

podans such as copepods, thecostracans and tantu-

locaridans cannot be grouped together with thè

Malacostraca on thè basis of thè division of thè post-

cephalic trunk into two tagmata (thorax and abdo-

men) because thè tagmata of maxillopodans and

malacostracans have a different somite composition

and are not homologous. «In other terms, according

to Boxshall & Huys tagmata are homologous in so

far as thè boundary between them lies in an homo¬

logous position. But, how is this positional homolo¬

gy to be determined? Is thè usuai count of segments,

with a more or less hypothetical acron as number

zero, a universally reliable reference? I do not think

so. To back my argument, I simply refer thè reader to

thè example in Figure 1, which I have discussed in

more detail in a recent paper (Minelli, 1992).

A good morphologist is able to avoid these seman-

tic pitfalls, but thè circumscription of characters to

consider for homology statements stili requires ad-

dressing and possibly solving additional questions. I

shall shortly touch on three points.

A fìrst question relates to thè contrast between

atomistic vs. holistic approach.

Wagner (1989a:58) has rightly stressed that «lack

of developmental individuality of parts may render

thè identifìcation of structures meaningless», but

one cannot be sure, at thè outset, that a thorough

knowledge of morphogenesis will grant recognition

Fig. 1 - How to compare position along thè body of a segment-

ed animai, if thè number of segments is not Constant within thè

species? A relative position (such as thè 35% of thè total number

of body segments, as determined in antero-posterior direction)

may be more meaningfully comparable than an absolute position

(such as thè 35th segment). At least, so is thè case illustrated in

thè figure.

In thè very slender, worm-like centipede Stigmatogaster gracilis

(Chilopoda: Geophilomorpha), thè number of body segments is

quite variable, even within a single population. However, seg¬

ment number does not increase with age: through thè several

moults they undergo during their post-embryonic life, these ani-

mais retain thè number of segments they possessed at birth. In a

few segments, which form an uninterrupted series a bit before

mid-length, thè ventral piate (sternum) is ‘marked’ by thè presen-

ce of a pair of lateral grooves. The number of sterna with grooves

increases with age. In addition, in thè animals with a smaller total

number of segments thè grooves occur in more anterior

segments than in animals with more segments. However, thè re¬

lative positions always remain thè same, as demonstrated by thè

figure, which shows thè linear regressions separately calculated

for thè relative segmentai position of thè fìrst and last segment

with grooves (black dots and open circles respectively) vs. body

length (BL), as observed in 66 Italian specimens of this species.

Relative segmentai positions (Xl/XT) are calculated by dividing

by thè total number of leg-bearing segments (XT) thè actual seg¬

mentai position X where thè groove series respectively begins or

ends. For both regressions, p <0.001 (after Minelli, 1992; repro-

duced here with thè permission of thè publisher, Universitàtsver-

lag Wagner, Innsbruck).

of individuai (atomic) units of comparison. This is

thè message conveyed by Goodwin and Trainor’s

(1983) theoretical analysis of digit differentiation in

tetrapod limbs. They contend that homologizing

limb elements involves an artificial atomism, whe-

reas, in their opinion, individuai skeletal elements do

not have an identity of their own. Rather, Goodwin

and Trainor’s holistic-structuralistic approach recog-

nizes thè whole limb as an integrated developmental

fìeld. In their view, when confronted with a 4- or

3-digit limb, we cannot say that one or two digits are

missing, e.g. thè fìrst or thè fìfth. What they regard as

thè only meaningful comparison is one involving thè

whole of thè digit-forming material present in thè

two instances: a digit-forming material that, in thè

case of thè digit-reduced appendages, only reaches

for 3 or 4 digits, rather than for thè 5 of ... how to

say?, thè 5 traditionally supposed to have been pres¬

ent in thè archetypal tetrapods (but see thè recent

evidence for a larger number of digits in early forms

like Ichthyostega ; Coates and Clack, 1990).

I am sincerely ready to take Goodwin and Trainor

(1983) seriously, is spite of thè difficulties raised by

Shubin & Alberch (1986:375), who claim that «if

Goodwin & Trainor (1983) took their approach to its

logicai conclusion, they could not discuss limb deve-

lopment and evolution in thè fìrst place, since this

requires them to use concept of homology at another

level of thè taxonomic hierarchy — to homologize a

structure called a limb in thè fìrst place. They impli-

citly accept a certain degree of compartmentalization

SOME THOUGHT ON HOMOLOGY 150 YEARS AFTER OWEN’S DEFINITION

75

by assuming that thè limb is an independent em-

bryonic fìeld [..] The degree of developmental com-

partmentalization corresponds to thè level at which

homologies can be resolved».

The challenge of thè holistic approach has been re-

cently extended into a fìeld that most developmental

biologists regard as a triumph of thè genetic dissec-

tion of a complex pattern, that of thè origin of body

segmentation in Drosophila. In thè study of this de¬

velopmental process, a whole gallery of ‘segmentai

monsters’ opened thè way to a wonderful genetic

analysis, beginning with Niisslein-Volhard & Wies-

chaus’s (1980) already classic paper. This analysis

progressively revealed thè individuai role of a lot of

genes, in establishing thè main features of body ar-

chitecture and of segmentation in particular. Of

many of these genes w e now know both thè sequen-

ce, thè spatial and temporal patterns of expression

and thè interactive effects with thè products of other

genes. Well, right against this compact body of ex-

perimental data, which all point in favour of thè indi¬

viduai roles of individuai genes in controlling speci-

fied aspects of body structure, Goodwin’s group (Ho

et al., 1987) have shown that Drosophila embryos, ex-

posed to ether between 1 and 4 h after deposition,

often develop segmentation defects resembling

known mutant phenotypes. Their conclusion is, that

«at least part of thè segmentation process may con-

sist of physicochemical reactions coordinateci over

thè whole body» (p. 511). Quite independently from

thè final judgement on thè mechanisms actually in-

volved in digit formation in vertebrates, or in body

segmentation in insects, I once more want to stress

thè danger of rushing towards atomistic descriptions

and, hence, comparisons.

This point, however, stili leaves us with thè ques¬

tioni where to begin? Perhaps — this is my second

point — with archetypes?

Young (1993:225) has recently argued «that nei-

ther thè concept of «structure» nor that of «homolo¬

gy» can be incorporated within a morphological

Science that lacks an archetypal foundation. By an ar-

chetypal concept I mean thè recognition of stable un-

derlying patterns within morphological systems».

From an ontological point of view, this «archety-

pe» seems to be immanent rather than transcendant,

thus quite different from Owen’s one. Nevertheless,

it is stili an essentialistic, rather than an empirical,

construction.

Worries in front of this persistent ghost of archety¬

pes seem to be largely responsive for thè widespread

shift of attention, in thè literature, from transforma-

tional, or biological, to taxic, or historical, homology.

For instance, Patterson (1982) only accepts thè taxic

notion of homology as synapomorphy, stating that

transformational homology is always validated by

reference to archetypes. However, as also asserted

by Panchen (1992:71), things are not necessarly

so, if our transformational comparisons rest, apart

from Geoffroy’s principle of connections, on thè

identification of similar developmental pathways in

ontogeny.

Summing up, I do not believe that thè ghost of ar¬

chetypes should be raised against transformational,

or biological, homology, any more than against taxic,

or historical, homology. As we have already seen,

both of them are able to generate groundplans, or

Ur-somethings. On thè contrary, both of them may

(and should!) content themselves with a minimum

requirement of starting hypotheses, when adopting a

given set of terms for describing, at thè outset, thè

objects to be later compared.

Moving soon to thè third, and last, point of this

section, a major trouble for students of homology

has long been thè fact, that features regarded as ho-

mologous are sometimes built, in different orga-

nisms, under thè control of different genes. A more

recent version of this problem is Roth’s (1988:7) ‘ge¬

netic piracy’, when «genes, previously unassociated

with thè development of a particular structure, can

be deputized in evolution, that is, brought in to con¬

trol a previously unrelated developmental process,

so that entirely different suites of genes may be res¬

ponsive for thè appearance of thè structure in differ¬

ent contexts».

I believe that in order to assess thè actual relevan-

ce, or even thè meaning, of Roth’s genetic piracy, we

would need a better knowledge of what we could cali

thè redundancy of genetic control over developmen¬

tal pathways. Leaving aside thè experimental aspects

of thè question, I feel, from a theoretical point of

view, that to ignore this redundancy is one aspect of

well-entrenched typologism and reductionism.

On thè contrary, recognizing that thè features we

are homologizing are subjected to a redundant con¬

trol, or that their history has seen episodes of genetic

piracy, is not a problem, whenever we develop a

combinatoria! view of homology, as outlined below.

An informational and combinatorial view

of homology relationship

Developmental biology has often demonstrated

that thè same body part can often be built out of ma¬

teriate with different origins. What is required, to get

those organs, seems rather to be thè spread of some

specifìc information through previously inert mate¬

riate. Some example follow, from a potentially enor-

mous literature (cf. Wagner 1989a), just to give an

idea of thè different levels through which this pheno-

menon spans.

Norris (1993) has shown that there is considerable

flexibility in thè makeup of thè tympanic bulla, with

variable incorporation of thè squamosal into thè

tympanic floor, within thè same population of a mar-

supial, thè grey cuscus ( Phalanger orientalis).

At thè other extreme of thè possible taxonomic

range, within Metazoa, our current awareness of

comparative embryology suggests that thè contribu-

tion of germ layers to various body parts can vary to

such an extent as to undermine thè very concept of

germs layers.

Even an apparently major difference, such as that

between cells vs. syncytia, seems to be of minor im-

portance, e.g. in some steps of insect body segmenta¬

tion, as shown by a comparison of Drosophila , with

its syncytial blastoderm, with thè lesser flour beetle

Tribolium, with cellularized blastoderm (Sommer

and Tautz, 1993).

Writing on homology right 50 years ago, Boyden

(1943:233-4) expressed thè view that «Homology is a

genetic phenomenon». This may sound like a sim-

plistic, reductive view of thè problem; nevertheless, it

can serve as a suitable starting point for thè following

argument.

76

ALESSANDRO MINELLI

I identify three major attributes of a biological

concept of homology. Two of them are thè infor-

mational background and thè relativity of homology

(cf. Minelli & Peruffo, 1991, and references therein),

from which we can easily derive thè third point, i.e.

thè compositional aspect of homology. This

approach (Minelli, 1992, 1993; Haszprunar 1992)

seems to me a way of integrating more strictly thè

different kinds of homology as identified by thè old

comparative anatomy and more recently redefined

by Ghiselin (1976).

The individuai features of thè phenotype are thè

outcome of a series of developmental choices (more

or less directly mapping onto thè genome), many if

not most of which can be identified, in principle, as

independent units of developmental control, either

as morphogenetic or as morphostatic constraints

(Wagner, 1993). In principle, again, we can sepa¬

rate thè processes leading to these developmen¬

tal choices or control, as individuai components of

thè overall informational background underlying a

given feature and, by consequence, its homology

with corresponding features of thè same organism

(serial homology) or of different organisms (special

homology).

A notion of relativity also solves thè problem of

thè lack of unbound transitivity in homology rela-

tionships, to which Paulus (1989:472) recently called

attention.

Adopting this conceptual framework may also

help addressing thè interpretation of thè so-called

‘intermediate’ structures, which seem to take part of

two or more different elements and are often, too

often, described in terms of ‘fusion of structures’

whereas, especially in ontogenetic terms, they would

much better be described as ‘nondisjunct’. Once

more, a botanical example: «If a shoot apex does not

differentiate lateral primordia, but remains a smooth

protuberance until it starts growing (i.e., increasing

its volume by celi divisions and celi stretching), so-

mething like thè corm of a lemnaceous plantlet deve-

lops. There is no ‘fusion’, but ‘lack of separation’; thè

resulting cormoid structure is unclassifiable as a

‘stem’ or ‘a leaf and to cali it ‘intermediate’ is highly

questionable; it is rather a chimeric merger» (Meeu-

se, 1986:14-15). I would like to describe in thè same

terms a lot of structures occurring in thè animai king-

dom, as thè so-called diplosegments of millipedes,

which are clearly ‘doublé segments’ ventrally, but

‘unitary’ dorsally.

Positional homology in developmental mechanics

and in comparative anatomy

The search for a suitable reference System within

which to identify homology relationships has often

moved away from thè tangible realm of histology

and anatomy proper, to develop in more abstract,

geometrical terms, as in D’Arcy Thompson’s (1917,

1942) coordinates and transformations, or, more re¬

cently, within thè new morphometrics of Fred

Bookstein and associates (e.g., Bookstein et al., 1985;

cf. also Rohlf & Marcus, 1993 but see Bookstein

(1994) for a recent rethinking on these matters,

ending up with a strong denial of thè possibility of

reconcile morphometry with a search for homo-

logies).

However, one could more legitimately search for,

so to say, intrinsic coordinate systems, as already

did Geoffroy Saint-Hilaire, who suggested that thè

network of blood vessels could provide a kind of

scaffolding against which to identify topographical

relationships. More recently, rather than thè vascular

supply to thè different body parts, other connecting

elements, such as muscles and especially nerves,

progressively gained in favour among comparative

anatomists, as suggestive of identifìable positions

and, hence, of homologies (cf. Remane (1963) for a

modera assessment of these matters). On thè whole,

thè relationships between nerves and innervated or-

gans are generally held as thè most reliable. One

wonders whether thè reliability of inferences of ho¬

mology from nerve connections may be justified by

thè role of nerves as morphogenetic tracers. Howe¬

ver, as noted by Bock (1989:338), such «Positional

tests [of homology] are not as simple as they appear.

A common one is to test thè homology of skeletal

muscles by their innervation, using thè assumption

that thè same nerve innervates homologous muscles

even when thè muscles change shape and bony

attachments drastically. In such tests, it is necessary

to first establish thè homology of thè nerves inde-

pendently, which is not an easy task, especially when

one is dealing with secondary and tertiary branching

of a nerve».

At any rate, things seem to be different in different

systems; see, for instance, thè results of Broadie &

Bate’s newest investigations (1993:350). In thè em-

bryo of Drosophila, individuai motor neurons form

stereotyped synapses on individuai, identified mus¬

cles. Broadie and Bate «used a mutant ( prospero ) that

removes or delays innervation to assay thè role of thè

presynaptic motor neurons in thè development of

thè receptive field of thè postsynaptic muscle. Pros¬

pero (pros) is not expressed in thè muscles or their

precursors. [They] find that thè muscle defines thè

correct synaptic zone in thè absence of thè motor

neuron by restricting putative guidance molecules to

this specialized membrane region. Furthermore, thè

muscle expresses functional transmitter receptors at

thè correct developmental time without innervation.

On thè other hand, thè muscle does not localize re¬

ceptors to thè synapse without instruction from thè

motor neuron, nor does a second, much larger, syn-

thesis of receptors occur in muscles deprived of in¬

nervation». These results suggest that, in this System

at least, thè role of muscles is not simply a passive

one, where all connections are specified in advance

by nerves.

However, even if a mechanistic, i.e. molecular, in¬

terpretation of thè primacy of nerves in establishing

a morphological reference System within thè animai

may stili sound doubtful, there seems to be much

scope for a molecular interpretation of thè Lois des

connexions, especially at thè level of gross morpholo¬

gical organization.

Let me introduce this point by focussing on an ele-

mentary, but generally overlooked feature of compa¬

rative anatomy. Within thè body architecture of all

animals, there are some ‘hot spots’ where many, or

most, of thè key features of thè body differentiate

and evolve. In most groups, thè most conspicuous of

these hot spots are thè two ends of thè body, but

there are also other, less conspicuous ‘hot spots’, a

few of which seem to be worthy of attention.

SOME THOUGHT ON HOMOLOGY 150 YEARS AFTER OWEN’S DEFINITION

77

Take, for instance, a male dragonfly. At variance

with thè generality of insects, it has not developed a

copulatory structure in strict anatomical connection

with its genital opening, but one several segments in

front of it. This morphological behaviour is quite

strange, although not unique within Metazoa, but I

am not recalling it here to discuss its origin, or to

trace any special homology of this secondary penis to

structures in other insects, but simply to point to an

unexpected topographical correspondence. In fact,

male gonopods in most millipede families are thè

modifìed appendages of what seems to be exactly thè

‘same’ segment as that with genital opening in dra-

gonflies, whereas thè secondary penis of dragonflies

occur at thè same segment where male millipedes

have their genital opening! These two segments also

behave as a kind of ‘hot spot’ (Minelli & Schram,

1994) where different arthropods are able to specify

different highly specialized structures. Why do all

these structures develop there, in spite of their very

different nature? Probably because thè ‘hot spots’

are evolutionarily homologous and have not chan-

ged their relative position, at least since thè lineage

leading to dragonflies split off from that leading to

millipedes. I see here a kind of positional homology,

despite a lack of special homology.

Recently, Slack et al. (1993) have tried to characte-

rize what they cali thè ‘zootype’, a kind of molecular

archetype of metazoans. This zootype would be

under thè specifìc control of thè so-called Hox genes.

Not that these genes actually specify any given struc¬

ture, such as mouth, brain, heart, kidney, or anus,

but they seem to lay down thè generai scaffolding

of thè body, by giving — in molecular terms — posi¬

tional value to thè different points along thè main

body axis.

I believe (cf. Minelli & Schram, 1993) that these

facts and models (thè zootype; thè segments with se¬

condary penis in dragonflies and gonopods in milli¬

pedes) are better discussed by reference to what may

be regarded, in a sense, quite thè opposite. I am

thinking of thè homoeotic mutants, where, in spite

of thè different positional specification, there is stili a

point-to-point structural correspondence (iterative

homology) between thè normal feature, e.g. a leg,

and its ectopie counterpart. On thè other hand, thè

position of thè ectopie leg of an Antennapedia mut-

ant is thè same as that of a normal antenna in a wild

type fly. But, when I say ‘in thè same position’,

I imply a kind of ‘positional homology’, to be eva-

luated independently from thè «special homology»

between thè appendages. But current molecular ge-

netics of development allows us to give a material

meaning to this positional homology, not less tang-

ibly so as it gives a material meaning to thè special

homology of structures whose differentiation we en-

visage as dependent on similar genetic control. — Let

me add, incidentali, that to speak of ‘ectopie legs’,

as is customary, literally implies wrong interpreta-

tions of facts: thè expression implies that a leg has

somehow changed its position, whereas it is another

appendage that has differentiated with properties

that usually are expressed in other positions.

Summing up, in this application of thè concept of

compositional homology mentioned before, there

seems to be scope for three interestingly different

kinds of comparisons: (a) those with conservation of

positional homology, but not of special homology,

(b) those with conservation of special homology, but

not of positional homology; (c) those with conser¬

vation of both kinds of homology, positional and

special.

The positional specification of thè main body axis

seems to be only one of thè Systems where these

Hox genes are involved. In vertebrates, they also

seem to function during embryogenesis of other

structures, such as thè limbs, thè skeleton and thè

nervous System, where regional variation of thè com-

ponents must be established along axial coordinates

(Krumlauf, 1993). In other instances, as in thè deve¬

lopment of insect appendages, there appears to be an

element of polar coordinate reference Systems (Bry-

ant, 1993). This polar System is coupled with a «seg-

mentation» process similar to that of thè main body

of arthropods wherein protein markers of annulin

mark thè limbs boundaries (Bastiani et al., 1992).

Positive knowledge of these genes, of their expres¬

sion patterns during early embryogenesis and of thè

relationships between corresponding Hox genes in

different metazoans are rapidly increasing. But we

do not need to wait for much experimental detail,

before we dare to suggest — right as a kind of re-

search programme for comparative molecular gene-

ticists — a reinterpretation of many facts of tradition-

al zoological wisdom.

Why is thè anatomy of flatworms generally so un-

stable, compared to that of insects or vertebrates?

(Russell, 1930). Is perhaps this fact a consequence of

thè lack of a hot spot at thè rear end of thè body?

Once established, body landmarks (hot spots) to-

pographically constrain subsequent morphogenetic

events (Minelli and Schram, 1994).

For instance, in digenean trematodes a mid-body

spot sets thè site for thè genital opening only, whe¬

reas in planarians both mouth and genital opening

appear there.

Again, in male nematodes a posterior, subterminal

spot marks thè cloacal opening, whereas in females

only an anus develops, thè genital pore being borne

on an additional mid-body spot. And so on.

Adopting a compositional view of homology and,

especially, extracting positional homology as a factor

of its own, poses many new, interesting problems.

For instance, whether there is a minimum size for

discrete pattern elements, as one could see, for ex-

ample, in thè subcellular kineties, acting as temple-

tes for ciliary structures in ciliates (Frankel, 1989).

One interesting feature is, that some animals are per¬

haps too small to get more than anterior/posterior

polarity, e.g., dieyemid mesozoans. Others are too

small to develop or retain segmentation, e.g. erio-

phyid mites (ca. 50 pm). This fact suggests a possibly

interesting field of investigation, that of thè grain of

biological forms. Of course, thè same animai or plant

will turn out to be fme-grained or coarse-grained ac-

cording to thè criteria of description. There is no ‘ab-

solute’ grain. Nevertheless, I think that comparative

morphology and evolutionary biology both have

much to learn from studies such as those of Shimizu

et al. (1993) on Hydra, or Weber (1992) on Drosophila.

Shimizu et al. have tried to determine thè minimum

tissue size required for regeneration in Hydra ; this size

tumed out to be some 270-300 epithelial cells, thè mini¬

mum number of cells that proved to be required for

going through thè criticai stage of hollow sphere, before

starting re-differentiation towards thè polyp form.

78

ALESSANDRO MINELLI

On selection, rather than regeneration, was thè

focus of Weber’s study. He tried to see, in his words

(p. 345), «whether thè necessary genetic potential ex-

ists for dense, finegrained, autonomous and locali-

zed adaptive change all over thè insect wing; or

whether thè potential for localized remodeling is

only coarse-grained and scattered here and there». In

selected cases, a very small wing region, of less than

100 cells across, did respond to selection almost inde-

pendently from thè behaviour of thè neighbouring

cells. Weber concluded that «thè control of develop-

mental detail must involve many genes, and thè di-

versity of possible outcomes in development and

adaptation must be large».

Concluding remarks

To conclude this walk through thè world, or

worlds, of homology: far from being an empty, or

useless or deceptive, old-fashioned concept, as many

students have contended in a not too distant past,

homology stili occupies a centrai place in compara¬

tive biology. Far from annihilating it, advances in ge-

netics and developmental biology have contributed

many valuable fìndings and ideas, on thè basis of

which our appreciation of homology has progressive-

ly improved. Finally, molecular biology provided thè

stuff for clearing thè field from that lasting ghost of

subjectivity, thè criteria for positional homology.

But this does not simply mean that homology has

no necessary connection with phylogeny, i.e. with

history, with time. Rather, it turns out to be thè cen¬

trai, though multi-faceted concept of a comparative

biology whose agenda we should perhaps articulate

in revised, explicit terms, 150 years after Owen’s defi-

nition of homology.

Acknowledgements - Best thanks are due to thè

organizers of thè workshop (Michael T. Ghiselin,

Giovanni Pinna and Francesco M. Scudo) for inviting

me to attend this very stimulating three-day meeting.

To Giovanni Pinna, in addition, my most sincere

appreciation of his friendly hospitality in Milano.

Drafts of my manuscript have been carefully read

and criticized by Michael Ghiselin, Franco Scudo

and Cesare Baroni Urbani, who all deserve my most

sincere thanks; of course, they do not share with me

any responsibility for thè final version, which retains

a lot of my most idiosyncratic views.

This work has been partly supported by grants of

thè Italian National Research Council (C.N.R.) and

of thè Italian Ministry of University and Scientifìc

and Technical Research (MURST).

REFERENCES

Bastiani M. J., de Couet H. G., Quinn J. M. A., Karlstrom R. O.,

Kotrla K., Goodman C. S. & Ball E. E., 1992 - Position-spe-

cifìc expression of thè annulin protein during grasshopper

embryogenesis. Dev. Biol., 154: 129-142.

Bock W., 1989 - The homology concept: its philosophical

foundation and practical methodology. Zool. Beitr. N. F.,

32: 327-353.

Bookstein F. L., 1994 - Can biometrical shape be a homologous

character? In: Hall B. K. (ed) Homology: thè hierarchical

basis of comparative biology. Academic Press , San Diego-New

York-Boston-London-Sydney-Tokyo-Toronto: 197-227.

Bookstein F. L., Chernoff B., Elder R. L., Humphries J. M.

jr., Smith G. & Strauss R., 1985 - Morphometrics in evolu-

tionary biology. The Academy of Naturai Sciences Special

Publication, Philadelphia, 15.

Boxshall G. A. & Huys R., 1992 - A homage to homology:

patterns of copepod evoiution. Acta Zool., Stockholm, 73:

327-334.

Boyden A., 1943 - Homology and analogy: a century after thè de-

fmition of «homologue» and «analogue» of Richard Owen.

Quart. Rev. Biol., 18: 228-241.

Broadie K. & Bate M., 1993 - Innervation directs receptor synth-

esis and localization in Drosophila embryo synaptogenesis.

Nature, 361: 350-353.

Bryant P. J., 1993 - The polar coordinate model goes molecular.

Science, 259: 471-472.

de Beer G. R., 1971 - Homology, an unsolved problem. Oxford

University Press, London.

Coates M. I. & Clack J. A., 1990 - Polydactyly in thè earliest

known tetrapod limbs. Nature, 347: 66-69.

Eldredge N. & Cracraft J., 1980 - Phylogenetic patterns and

thè evolutionary process. Methods and theory in compara¬

tive biology. Columbia University Press, New York.

Enghoff H., 1990 - The ground-plan of thè chilognathan milli-

pedes (external morphology). In: Minelli A. (ed) Procee-

dings of thè 7th International Congress of Myriapodology.

E. J. Brill, Leiden: 1-21.

Frankel J., 1989 - Pattern formation: cibate studes and models.

Oxford University Press, New York.

Geoffroy Saint-Hilaire E., 1807 - Considération sur les pièces

de la tète osseuse des animaux vertébrés et particulièrement

sur celles du cràne des oiseaux. Ann. Mus. Hist. nat. Paris, 10:

342-365.

Geoffroy Saint-Hilaire E., 1818-22 - Philosophie anatomique.

J. B. Ballière, Paris.

Geoffroy Saint-Hilaire E., 1830 - Principes de philosophie

zoologique discutés au sein de l’Académie Royale des Scien¬

ces. Pichon et Didier, Paris.

Ghiselin M. T., 1976 - The nomenclature of correspondence: A

new look at «homology» and «analogy». In: Masterton R. B.,

Hodos W. & Jerison H. (eds). Evoiution, brain, and beha-

vior: Persistent problems. Lawrence Erlbaum Associates

Pubi. Hillsdale, N. J.: 129-142.

Goodwin B. C. & Trainor L., 1983 - The ontogeny and phylo¬

geny of thè pentadactyl limò. In: Goodwin B., Holder N.

& Wylie C. (eds). Development and evoiution. Cambridge

University Press, Cambridge: 75-98.

Haszprunar G., 1992 - The types of homology and their signifi-

cance for evolutionary biology and phylogenetics. J. evol.

Biol., 5: 13-25.

Hennig W., 1950 - Grundziige einer Theorie der phylogenetis-

chen Systematik. Deutscher Zentralverlag, Berlin.

Hennig W., 1966 - Phylogenetic Systematics. Translated by

D. D. Davis and R. Zangerl. Urbana University Press, Urba¬

na, 111.

Ho M.-W., Matheson A., Saunders P. T., Goodwin B. C. &

Smallcombe A., 1987 - Etner-induced segmentation distur-

bances in Drosophila melanogaster. Roux’s Arch. dev. Biol.,

196: 511-521.

Kaufmann S. A., 1993 - The origins of order. Oxford University

Press. New York.

Krumlauf R., 1993 - Hox genes and pattern formation in thè

branchial region of thè vertebrate head. Trends in Genetics, 9 :

106-112.

Laudan R., 1992 - What’s so special about thè past? In: Nite-

cki M. N. & Nitecki D. V. (eds). History and evoiution. State

Univ. of New York Press, Albany: 55-67.

Lenoir T., 1982 - The strategy of life. D. Reidei, Dordrecht.

Màgdefrau K., 1992 - Geschichte der Botanik. Leben und

Leistungen groBer Forscher. Zweite Auflage. Gustav Fischer

Verlag, Sttutgart.

Martinez E. & Ramos C. H., 1989 - Lacandoniaceae (Triurida-

les): Una nueva familia de México. Ann. Missouri bot. Gard.,

76: 128-135.

Meeuse A. D. J., 1986 - Anatomy of morphology. E. J. Brill/Dr.

W. Backhuys, Leiden.

Minelli A., 1992 - Towards a new comparative morphology of

myriapods. Ber. nat.-med, Verein Innsbruck, suppl. 10: 37-46.

Minelli A., 1993 - The agenda of comparative morphology and a i

compositional view of homology. Submitted.

SOME THOUGHT ON HOMOLOGY 150 YEARS AFTER OWEN’S DEFINITION

79

Minelli A. & Peruffo B., 1991 - Developmental pathways, ho-

mology and homonomy in metamerie animals J. evol. Biol.,

4: 429-445.

Minelli A. & Schram F. R., 1994 - Owen revisited: A reappraisal

of morphology in evolutionary biology. Bijdri Dier K., 64:

65-74.

Nelson G., 1978 - Ontogeny, phylogeny and thè biogenetic law.

Syst. Zool., 27: 324-345.

Nelson G. & Platnick N., 1981 - Systematics and biogeography.

Cladistics and vicariance. Columbia University Press, New

York.

Nijhout H. F., 1991 - The development and evolution of butterf-

ly wing patterns. Smithsonian Institution Press, Washington

and London.

Norris C. A., 1993 - Changes in thè composition of thè auditory

bulla in southern Solomon populations of thè grey cuscus

Phalanger orientalis breviceps (Marsupialia, Phalangeridae).

Biol. J. Linn. Soc., 107: 93-106.

Nusslein-Volhard C. & Wieschaus E., 1980 - Mutations affect-

ing segment number and polarity in Drosophila. Nature, 287:

795-801.

Owen R., 1843 - Lectures on thè comparative anatomy of inverte-

brates. Longman, Brown, Green and Longmans, London.

Panchen A. L., 1992 - Classification, evolution and thè nature of

biology. Cambridge Univ. Press, Cambridge.

Patterson C., 1982 - Morphological characters and homology.

In: Joysey K. A. and Friday A. D. (eds) Problems of phyloge-

netic reconstruction. The Systematics Association Special

Volume No. 21. Academic Press, London: 21-74.

Patterson C., 1983 - How does phylogeny differ from ontogeny?

In: Goodwin B. C., Holder N. and Wylie C. C. (eds). Deve¬

lopment and evolution. Cambridge University Press, Cam¬

bridge: 1-31.

Paulus H. F., 1989 - Das Homologisieren in der Feinstruktur-

forschung: Das Bolwig-Organ der hòheren Dipteren und

seine homologisierung mit Stemmata und Ommatidien

eines ursprùnglichen Fazettenauges der Mandibulata. Zool.

Beitr., N. F., 32: 437-478).

Remane A., 1963 - Uber die Homologisierungsmòglichkeiten bei

Verbindungsstrukturen (Muskeln, BlutgefaBen, Nerven)

und Hòhlràumen. Zool. Anz., 166: 481-489.

Riedl R., 1980 - Die Entwicklung des Begriffs vom taxonomis-

chen Merkmal oder das Problem der Morphologie. Zool.

Jahrb. Anat., 103: 155-168.

Rohlf F. J. & Marcus L. F., 1993 - A revolution in morpho-

metrics. Trends in Ecology and Evolution, 8: 129-132.

Roth V. L., 1988 - The biological basis of homology. In: Humph-

ries C. J. (ed). Ontogeny and systematics. British Museum

(Naturai History), London: 1-26.

Russel E. S., 1930 - The interpretation of development and he-

redity. Clarendon Press, Oxford.

Serres M., 1827 - Recherches d’anatomie transcendante, sur les

lois de l’organogénie appliquées à l’anatomie pathologique.

Ann. Sci. nat. Paris, 11: 47-70.

Shimizu H., Sawada Y. & Sugiyama T., 1993 - Minimum tissue

size required for hydra regeneration. Dev. Biol., 155: 287-296.

Shubin N. H. & Alberch P., 1986 - A morphogenetic approach to

thè origin and basic organization of thè tetrapod limb. Evol.

Biol, 20: 319-387.

Slack J. M. W., Holland P. W. H. & Graham C. F., 1993 - The

zootype and thè phylotypic stage. Nature, 361: 490-492.

Sneath P. H. A. & Sokal R. R., 1973 - Numerical taxonomy.

W. H. Freeman, San Francisco.

Sokal R. R. & Sneath P. H. A., 1963 - Principles of numerical

taxonomy. W. H. Freeman, San Francisco.

Sommer R. J. & Tautz D., 1993 - Involvement of an orthologue of

thè Drosophila pair-rule gene hairy in segment formation of

thè short-germ embryo of Tribolium (Coleoptera). Nature,

361: 448-450.

Thompson D’A. W., 1917, 1942 - On growth and form. Cambridge

University Press, Cambridge.

Tuomikoski R., 1967 - Notes or some principles of phylogenetic

systematics. Ann. Ent. Fenn., 33: 137-147.

Turpin P. J. F., 1837 - Atlas contenant deux planches d’anatomie

comparée, trois de botanique et deux de géologie. (As an

appendix to: Martins C. F., Oevres d’histoire naturelle de

Goethe). Paris.

Wagner G. P., 1989a - The biological homology concept. Ann.

Rev. Ecol. Syst., 20: 51-69.

Wagner G. P., 1989b - The origin of morphological characters

and thè biological basis of homology. Evolution, 43: 1157-1171.

Wagner G. P., 1994 - Homology and thè mechanisms of develop¬

ment. In: Hall B. K. (ed) Homology: thè hierarchical basis of

comparative biology. Academic Press, San Diego-New York-

Boston-London-Sydney-Tokyo-Toronto: 237-299.

Wake D. B., & Larson A., 1987 - Multidimensional analysis of an

evolving lineage. Science, 238: 42-48.

Weber K. E., 1992 - How small are thè smallest selectable do-

mains of form? Genetics, 130: 345-353.

Young B. A., 1993 - On thè necessity of an archetypal concept in

morphology: with special reference to thè concepts of «struc-

ture» and «homology». Biology and Philosophy, 8: 225-248.

Alessandro Minelli: Dipartimento di Biologia Università di Padova, Via Trieste 75, 35121 Padova, ITALIA

Systematic Biology as an Historical Science

Memorie della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano

Volume XXVII - Fascicolo I - 1996

.

-• ■

.

Robert J. O’Hara

Trees of history in systematics and philology

Abstract — «The Naturai System» is thè name given to thè underlying arrangement present in thè diversity of life. Unli-

ke a classifìcation, which is made up of classes and members, a System or arrangement is an integrated whole made up of

connected parts. In thè pre-evolutionary period a variety of forms were proposed for thè Naturai System, including maps,

circles, stars, and abstract multidimensional objects. The trees sketched by Darwin in thè 1830s should probably be con¬

sideraci thè first genuine evolutionary diagrams of thè Naturai System — thè first genuine evolutionary trees. Darwin refi-

ned his image of thè Naturai System in thè well-known evolutionary tree published in thè Origin ofSpecies, where he also

carefully distinguished between arrangements and classifìcations. Following thè publication of thè Origin, there was a great

burst of evolutionary tree building, but interest in trees declined substantially after 1900, only to be revived in recent years

with thè development of cladistic analysis.

While evolutionary trees are modera diagrams of thè Naturai System, they are at thè same time instances of another

broad class of diagrams that may be called «trees of history»: branching diagrams of genealogical descent and change. Dur-

ing thè same years that Darwin was sketching his first evolutionary trees, thè earliest examples of two other trees of history

also appeared: thè first trees of language evolution and of manuscript genealogy. Though these were apparently independ-

ent of evolutionary trees in their origin, thè similarities among all these trees of history, and among thè historical processes

that underlie them, were soon recognized. Darwin compared biological evolution and language evolution several times in

thè Origin of Species, and both Ernst Haeckel and thè linguist August Schleicher made similar comparisons. Both linguists

and stemmaticists (students of manuscript descent) understood thè principle of apomorphy — thè principle that only shared

innovations provide evidence of common ancestry — more clearly than did systematists, and if there had been more cross-fer-

tilization among these fields thè cladistic revolution in systematics might well have taken place in thè nineteenth century.

Although historical linguists and stemmaticists have in some respects had sounder theory than have systematists, at least

until recently, they have also had thè practical problem of very large amounts of data, a problem not often faced by syste¬

matists until thè advent of molecular sequencing. The opportunity now exists for systematists to contribute to thè theory

and practice of linguistics and stemmatics, their sister disciplines in historical reconstruction, through application of our

commonly used computer programs for tree estimation. Preliminary results from thè application of numerical cladistic

analysis to a large stemmatic data set have been very encouraging, and have already generated much discussion in thè

stemmatics community.

Introduction

In a series of influential papers beginning in thè

1960s, Michael Ghiselin challenged a view common

among philosophers of Science that species, thè basic

unit of systematics, are best thought of ontologically

as naturai classes (Ghiselin, 1966, 1974, 1984, 1987).

Rather than seeing species as classes of organisms,

Ghiselin argued that they should in fact be regarded

as complex, historical individuals: singular things

which have particular spatial and temporal distribu-

tions, and which have individuai organisms as their

parts rather than as their members. Although this

view of thè ontological status of species was initially

rejected by many philosophers, it has since come to

be widely accepted (Hull, 1975, 1978; O’Hara, 1988b).

Although Ghiselin was primarily concerned with

thè ontological status of species in these papers, it

was implicit in his position that higher taxa must also

be individuals in a certain sense (Ghiselin 1984: 85),

individuals made up of species which are their parts,

just as any whole human body is made up of indivi¬

duai organs. In this paper I have two aims. The first

aim, following Griffìths (1974), de Queiroz (1988),

and my own earlier work (1993), is to develop thè no-

tion that higher taxa are ontological individuals or

systems, as Ghiselin had implied, and to demonstrate

that reflective systematists have long regarded them

as such. My second aim is to show that evolutionary

trees, our modern representations of thè single Natu¬

rai System, are also examples of another class of his¬

torical representations which may be called «trees of

history». As such they can be profitably studied,

from both theoretical and practical perspectives, in

conjuntion with other trees of history such as genea¬

logical diagrams of language evolution and of ma¬

nuscript descent. By putting evolutionary trees in thè

context of other trees of history we will be better able

to see thè many similarities that tie together thè enti-

re range of thè historical Sciences.

Higher taxa as systems rather than classes

The ontological status of higher taxa has attracted

some attention in thè recent systematic literature,

and Ghiselin’s distinction between classes and indi¬

viduals is often expressed in this literature as a dis¬

tinction between classifìcations on thè one hand, and

systems or arrangements on thè other (Griffìths, 1974;

Ax, 1987; de Queiroz, 1988; Minelli, 1993; O’Hara,

1993). A classifìcation is a collection of classes each

of which contains elements or members. The only

important relationship among thè elements of a clas¬

sifìcation is thè relationship of inclusion: class A may

contain class B, or it may be contained within class B,

or it may be independent of class B entirely. In con-

trast to a classifìcation, a System is an integrated,

connected whole that is not made up of classes, but

is instead made up connected parts. In a System there

are many more relationships among thè parts than

simple inclusion. There are, for example, positional

relationships: parts are not simply components of

larger parts, they may also be to thè left or right, to

82

ROBERT J. O’HARA

thè north or south, earlier or later, above or below

other parts within thè System.

We can understand thè distinction between classi-

fications and systems more clearly if we contrast a

map (as a System) with a geographical classifìcation.

It would be possible to construct a classifìcation of

places in Europe, with «Europe» as thè largest class,

including Italy, France, Germany, Spain, England,

IDEE DUNE ECHELLE

D E S E 1 R E S N A l' U R E E S.

Fig. 1 - The Scala Naturae or Chain of Being, from Bonnet (1745).

Bonnet’s originai figure is a single folding column. This Chain of

Being cannot be reduced to a classifìcation without loss of infor-

mation, because it represents a System of relationships more

complex than simple inclusion.

Ireland, and so on. Included under thè heading

«Italy» in this classifìcation would be Milan, Rome,

Bologna, Venice, and Naples; under thè heading

«England» would be London, Cambridge, Liverpool,

Oxford, and Sussex; and so on. But if this classifica-

tion of places is all we know of geography, then we

do not know a great deal. We do not know whether

Rome is north or south or east or west of Milan; we

do not know whether Oxford is north or south or

east or west of London. This is because thè classifica-

tion expresses only relationships of inclusion. We

may contrast a geographical classifìcation of this sort

with a geographical map, which is an integrated

whole: a System. A map of Europe will communicate

not only relationships of inclusion — that Milan and

Rome are both within Italy — but also positional rela¬

tionships in geographical space: Milan is north of

Rome, and Oxford is west of London.

The distinction between classifications and Sys¬

tems or map-like arrangements is important because

classifìcation, as a distinct intellectual activity, has

been overemphasized by many writers on systemat-

ics and its history. Many systematists of thè past, es-

pecially thè reflective ones, did not see themselves as

constructing classifications, but rather as recons-

tructing a large particular object they called thè Na¬

turai System (O’Hara, 1993), and for these workers

thè Naturai System was a rich and multi-faceted idea,

far more complex than any classifìcation could poss-

ibly be. Consider, for example, one of thè earliest

images of thè Naturai System: thè image of thè Scala

Naturae or Chain of Being (Lovejoy, 1936). Figure 1

shows an eighteenth-century representation of thè

Chain of Being, drawn by thè entomologist Charles

Bonnet in 1745. The information conveyed in this

systematic arrangement cannot be reduced to a

simple classifìcation without loss of information, be¬

cause thè arrangement depicts not only relationships

of inclusion but also positional relationships along

thè chain: «Oiseaux» does indeed contain many taxa

which are not enumerated, but in addition Oiseaux is

above Poissons and below Quadrupedes.

As thè diversity of life became better known in thè

late eighteenth and early nineteenth centuries, syste¬

matists carne to realize that thè Chain of Being was

an inadequate representation of thè Naturai System,

and a great variety of more complex representations

were developed and put forward (Stevens, 1982, 1984;

Barsanti, 1988; O’Hara, 1988a, 1991). The quinarian

school of systematists led by William Sharpe Ma-

cleay (1819-21) and William Swainson (1836-37), for

example, argued that thè Naturai System is held to-

gether by interlocking relationships of affìnity and

analogy, and that these relationships displayed nu-

merical regularity. Arguing against thè quinarians,

Hugh Strickland (1841) and Alfred Russel Wallace

(1856) represented thè Naturai System as an irregular

map-like entity (Fig. 2) held together by affinities

only, affinities that in Strickland’s view could some-

times be circular or loop-like.

With thè acceptance of thè principle of common

descent, thè notion of thè Naturai System was con-

verted from a System of ideal affinities to one of phy-

sical genealogy (Darwin, 1859: 485). Almost as soon

as he became convinced of thè truth of thè theory of

descent, Darwin began to sketch evolutionary trees

in his notebooks (Darwin, 1987: 177-180), and thè

only diagram in thè Origin of Species itself is Dar-

TREES OF HISTORY IN SYSTEMATICS AND PHILOLOGY

83

Jìfdp of Uve, Farruty c&ce- .

Fig. 2 - «Map of thè Family Alcedinidae», from Strickland (1841). Relationships of afFinity connect each genus, and a «Scale

of Degrees of Generic Affìnity» appears in thè lower right corner. Although none are shown here, Strickland believed it

was possible for chains of affìnity to doublé back on themselves, forming a loop.

win’s well-known representation of an evolutionary

tree. Very soon after thè publication of thè Origin,

evolutionary trees began to appear in thè generai sys-

tematic literature, and their history between 1859

and 1900 is very complex. The elaborate phylogenies

of Ernst Haeckel are among thè best known (Oppen-

heimer, 1987), but many other authors drew trees

also (Figs. 3 and 4) and there was much discussion of

thè methods of phylogenetic reconstruction (Reif,

1983; Stevens, 1984; O’Hara, 1988a, 1991; Craw, 1992;

Darwin, 1993: 379-380). It became clear to some sys-

tematists at this time, for example, that only shared

innovations could count as evidence of common an-

cestry, and that shared retentions (today called

ancestral character States or plesiomorphies) were

Peristeropodes Alectoropodes

CARINATiE RATIT2E.

Fig. 3 - A phylogeny of birds, from Huxley (1868). Like many sys-

tematists of his time, Huxley published tree diagrams but did not

explain in detail thè procedure he followed in constructing them.

phylogenetically uninformative (Mitchell, 1901;

O’Hara, 1988a; Craw, 1992).

Around 1900, however, interest in phylogenetic re¬

construction began to flag, and as «biologists focu-

sed ever more intently on problems of organic func-

tion they transferred their allegiance from thè ideal

of historical explanation, thè criticai support for all

who had studied organic form and transformation, to

thè promise extended by thè experimental investiga-

tion of vital processes» (Coleman, 1977: 160). This

shift in interest was not universal (Craw, 1992), but it

was widespread (Alien, 1975; Zuckerman, 1976; Cole¬

man, 1977; O’Hara, 1988a, 1991). Historical approa-

ches were denigrated as «speculative» (T. H. Morgan

in Mayr, 1982: 542) for much of thè century, and it

was not until thè widespread acceptance of cladistic

analysis, beginning in thè 1970s, that phylogenetic

reconstruction attained prominence again.

Trees of history

Let us now consider evolutionary trees in their

other intellectual context, as examples not only of

diagrams of thè Naturai System, but also as «trees of

history». During thè very decades when Lamarck

was offering his first speculations on thè transforma¬

tion of species and Lyell was laying thè foundations

of modern historical geology, scholars in thè fìeld of

comparative philology were sketching thè outlines of

a new historical Science of language and literature.

Although thè development of philology in thè late

1700s and early 1800s was complex (Pederson, 1931;

Aarsleff, 1967; Burrow, 1967), modern-day linguistic

historians often point to a statement made by thè

84

ROBERT J. O’HARA

Fig. 4 - The evolution of thè tubinarial birds, from Forbes (1882). The meaning of thè circles and thè positions of thè genera

are not explained in Forbes’s text.

English jurist Sir William Jones as thè traditional

starting point of their discipline. Jones was one of

thè fìrst Europeans to learn Sanskrit, thè classical

language of India, and he noticed a number of strik-

ing similarities between Sanskrit on thè one hand,

and Greek and Latin on thè other. He concluded that

these similarities were mudi too remarkable to have

arisen by chance, and that no philologist could exa-

mine all three languages — Latin, Greek, and Sansk¬

rit — «without believing them to have sprung from

some common source, which, perhaps, no longer ex-

ists» (Jones, 1786). The historical study of this family

of languages, which carne to be called Indo-Euro-

pean and which stretches from Ireland to India, con-

tinued at great speed in thè early 1800s. The fìrst ge¬

nuine tree diagram of thè history of Indo-European

(and of any family of languages) was apparently pu¬

blished around 1800 (Auroux, 1990), but linguistic

trees of history didn’t really become widespread

until thè 1850s, even though thè concept of historical

families of languages had been clear for some time

by then. Frantisek Celakovsky, a professor of philo-

logy at Prague, published a genealogical diagram of

thè Slavic languages in 1850 (Fig. 5; Priestly, 1975),

but it was thè German philologist August Schleicher

— who had spent time in Prague and may been in-

fluenced there by Celakovsky (Holm, 1972) — who fì-

Fig. 5 - A family tree of thè Slavic languages by Frantisek

Celakovsky, published posthumously in 1853. Celakovsky’s

work may well have influenced August Schleicher, whose own

genealogical diagrams have often been regarded as thè fìrst trees

of language evolution (Priestly, 1985).

nally popularized thè use of tree diagrams in histori¬

cal linguistics through his widely-read publications

(Hoenigswald, 1975; Stewart, 1976; Koerner, 1982,

1987; Priestly, 1985).

The historical study of languages was only one of

thè tasks of comparative philologists, however; thè

other was thè study of thè history of written texts.

Most works of ancient literature do not exist today in

TREES OF HISTORY IN SYSTEMATICS AND PHILOLOGY

85

copies written by thè authors themselves — rather,

they are known from copies of thè originals, and co¬

pies of those copies, often made over a period of

hundreds of years and with varying degrees of care.

Philologists who specialize in thè study of texts are

faced with a very specifìc problem: given ten or twen-

ty or a hundred copies of thè same text, all of which

differ at different points, how can we determine thè

exact words of thè lost originai? The answer is that

we can determine thè originai of thè text by recons-

tructing thè tree — or as manuscript scholars cali it,

thè stemma — of thè copies that now exist. The idea

of an ancestral text represented today only by its va¬

rying descendants had been clear to manuscript

scholars for a long time, but as was thè case in syste-

matics and linguistics, thè first actual illustrations of

manuscript stemmata do not appear until thè early

1800s. The first published stemma appears to have

been that of Cari Johan Schlyter (Holm, 1972), and it

appears in 1827, fully formed like Athena from thè

head of Zeus. Schlyter and his collaborator Hans

Collin had been commissioned by thè King of Swe-

den to research thè history of medieval Swedish law,

and they made an exceptionally comprehensive

study of all thè medieval legai documents then

known. Many of these documents were multiple co¬

pies of originai texts that had been lost, and in one

such case, in order to «make thè relationship all thè

clearer between thè codexes now described», wrote

Schlyter, «containing in whole or in part thè text of thè

Vàstergòtland Law..., we have attempted to present

their affinities, as far as we could determine them from

mutuai agreements and differences, in a kind of family-

tree» (Fig. 6; Collin & Schlyter, 1827, translated by

Holm, 1972: 51-52). Very shortly after Schlyter’s tree

was published, a series of other manuscript stemmata

appeared in rapid succession. Cari Zumpt published a

genealogy of thè known copies of Cicero’s Verrine Ora¬

ti ons in 1831, and Zumpt’s stemma was followed by

stemmata drawn by Friedrich Ritschl in 1832, and by

J. N. Madvig in 1833. Holm (1972) has reproduced all

of these along with several other early stemmata.

As we saw in thè case of systematics, after thè pu-

blication of thè 0 rigin of Species there was a great

burst of tree-making, and much discussion of phylo-

genetic theory. This same period — thè late 1800s —

was similarly a golden age of historical philology. Lin-

guistic and textual scholars did an extraordinary

amount of work reconstructing thè details of thè evolu-

tionary history of thè Indo-European languages during

these years (Pederson, 1931; Morpurgo Davies, 1975;

Hoenigswald, 1990), and establishing thè originai texts

of Classical and Medieval authors through thè recons-

truction of manuscript stemmata (Timpanaro, 1981;

Reynolds, 1983). It did not escape notice at thè time that

thè goals of thè new naturai historians and thè goals of

thè new historical philologists were similar in many res-

pects (Hoenigswald & Wiener, 1987; Hoenigswald,

1990). August Schleicher, for example, published on

Die Danvinsche Theorie und die Sprachwissenschaft

(Schleicher, 1863), and his work caught thè attention

of Ernst Haeckel as well (Maher, 1966; Koerner, 1981,

1983). And like thè systematists, thè philologists in-

terested in tree reconstruction quickly recognized

that only shared innovations could be used as evi-

dence of common ancestry (Hoenigswald, 1990).

In another remarkable parallel to systematics, ho-

wever, interest in many of these large-scale problems

Fig. 6 - A stemma of several copies of thè Vàstgòta Law, drawn by

Cari Johan Schlyter (Collin & Schlyter, 1827). The vertical axis

represents absolute time, thè interval between each dotted line

being fifty years. The similarity of this diagram to Darwin’s evo-

lutionary tree in thè Origin of Species is striking, but apparently

coincidental.

of historical philology began to wane around thè turn

of thè twentieth century. Many manuscript scholars

carne to believe that horizontal transmission of rea-

dings between manuscripts — called «contamina-

tion» in stemmatics — was so widespread that any

hope of reconstructing true stemmata was in vain.

And linguists began to distinguish between what

they called diachronic or historical studies of langu-

age on thè one hand, synchronic or structural studies

of language on thè other, and began to regard syn¬

chronic, structural linguistics as thè most «scientifìc»

approach to their field. Much of linguistics since 1900

has been profoundly ahistorical, almost completely

turning its back on thè achievements of thè nine-

teenth century (Haas, 1966; Anttila, 1989).

86

ROBERT J. O’HARA

But systematics has re-historicized itself in thè last

thirty years, and there is reason to hope that thè

same thing may happen in linguistics and textual stu-

dies as well, and it may happen with some cross-dis-

ciplinary help from systematics. Some valuable inter-

disciplinary forays have been made in recent years

(Hoenigswald & Wiener, 1987; Flight, 1988; Lee,

1989) and these hold much promise. A collaboration I

began in 1991 with a textual scholar who is interested in

thè application of computers to stemmatics has also ge-

nerated much interest, and our application of cladistic

analysis to thè history of manuscript traditions has met

with considerable success (Fig. 7; Robinson & O’Hara,

1992, in press; O’Hara & Robinson, 1993).

Conclusion

One of thè first scholars to study thè interrelation-

ships of thè historical Sciences was thè polymathic

British philosopher William Whewell , who was born

just two hundred years ago, in 1794. Whewell coined

thè term «palaetiology» for these Sciences, and offe-

red geology, philology, and archeology as examples.

Had Whewell become an evolutionist he surely

would have included thè historical Science of syste¬

matics in thè group as well. The palaetiological

Sciences, Whewell realized, cut across many conven-

tional disciplinary boundaries, including even thè

boundary between Science and thè humanities. And

yet all of these Sciences «are connected by this bond;

— that they all endeavour to ascend to a past state, by

considering what is thè present state of things, and

what are thè causes of change» (1847: 638). The re-

construction of trees of history is one of thè common

themes of thè palaetiological Sciences, but they share

many other themes as well, such as thè principle of

uniformitarianism, which has been applied not only

in geology but also in linguistics (Johnes, 1843;

Christy, 1983; Naumann, et al., 1992). Whewell’s term

«palaetiology» never attained thè currency he had

hoped it would during his lifetime, but in our own

day, as thè ahistorical tenor of thè mid-twentieth

century recedes into thè past, thè term may be due

for a revival. Not since thè nineteenth century have

Whewell’s insights rung so true:

As we may look back towards thè first condition of our planet, we

may in like manner tura our thoughts towards thè first condition

of thè solar System, and try whether we can discern any traces of

an order of things antecedent to that which is now established;

and if we find, as some great mathematicians have conceived, in-

dications of an earlier state in which thè planets were not yet ga-

thered into their present forms, we have, in pursuit of this train of

research, a palaetiological portion of Astronomy. Again, as we

may inquire how languages, and how man, have been diffused

over thè earth’s surface from place to place, we may make thè like

inquiry with regard to thè races of plants and animals, founding

our inferences upon thè existing geographical distribution of thè

animai and vegetable kingdoms: and thus thè Geography of

Plants and of Animals also becomes a portion of Palaetiology.

Again, as we can in some measure trace thè progress of Arts from

nation to nation and from age to age, we can also pursue a similar

investigation with respect to thè progress of Mythology, of Poe-

Aarsleff H., 1967 - The Study of Language in England, 1780-

1860. Princeton University Press, Princeton.

Allen G., 1975 - Life Science in thè Twentieth Century. John

Wiley <£ Sons, New York.

Anttila R., 1989 - Historical and Comparative Linguistics. John

Benjamins, Amsterdam.

try, of Government, of Law . . . It is not an arbitrary and useless

proceeding to construct such a Class of Sciences. For wide and

various as their subjects are, it will be found that they have all

certain principles, maxims, and rules of procedure in common;

and thus may reflect light upon each other by being treated to-

gether (Whewell, 1847: 639-640).

Fig. 7 - A stemma of thè Old Norse narrative Svipdagsmàl, from

Robinson & O’Hara (1993, in press). This stemma was produced

with thè cladistic analysis software PAUP (Swofford, 1991), and it

is very similar to thè stemma produced by Robinson alone using

traditional non-cladistic means (Robinson, 1991). This tree was ge-

nerated much more quickly, however, thereby allowing thè textual

scholar more time for criticai study and analysis of thè result.

Acknowledgements — I am grateful to Michael Ghi-

selin for his invitation to participate in thè Workshop

on Systematic Biology as an Historical Science at thè

Museo Civico di Storia Naturale, and to Giovanni

Pinna, thè Museum’s director, for his gracious hospi-

tality during my stay in Milan. The participants in thè

workshop made many valuable comments on my

presentation, and Shannon Downer, Mary Johnson,

and Sheila Schurer assisted in thè preparation of thè

manuscript. Peter Robinson and Jeffrey Wills have

contributed substantially to my understanding of thè

history of philology.

Auroux S., 1990 - Representation and thè place of linguistic

change before comparative grammar. In: Leibniz, Hum¬

boldt, and thè Origins of Comparativism (T. de Mauro &

L. Formigari, eds.). John Benjamins, Amsterdam: 213-238.

Ax P., 1987 - The Phylogenetic System. John Wiley & Sons, New

York.

TREES OF HISTORY IN SYSTEMATICS AND PHILOLOGY

87

Barsanti G., 1988 - Le immagini della natura: scale, mappe, albe¬

ri 1700-1800. Nuncius, Firenze, 3: 55-125.

Bonnet C., 1745 - Traité d’Insectologie, premier parte. Durand,

Paris.

Burrow J. W., 1967 - The uses of philology in Victorian England.

In: Ideas and Institutions of Victorian Britain (R. Robson,

ed.). Barnes & Noble,_ New York: 180-204.

Celakovsky F. L., 1953 - Cteni o srovnavaci mluvnici slovanské

na université Prazské. F. Rivnàc, Prague.

Christy T. C., 1983 - Uniformitarianism in Linguistics. John

Benjamins, Amsterdam.

Coleman W., 1977 - Biology in thè Nineteenth Century: Pro-

blems of Form, Function, and Transformation. Cambridge

University Press, Cambridge.

Collin H. S. & Schlyter C. J., 1827 . Corpus Iuris Sueo-Goto-

rum Antiqui. Z. Haeggstrom, Stockholm, 1.

Craw R., 1992 - Margins of cladistics: identity, difference and

place in thè emergence of phylogenetic systematics, 1864-

1975. In: Trees of Life: Essays in Philosophy of Biology

(P. Griffiths, ed.). Australasian Studies in History and Philo¬

sophy of Science, 11: 65-107.

Darwin C., 1859 - On thè Origin of Species. John Murray,

London.

Darwin C., 1987 - Charles Darwin’s Notebooks, 1836-1844.

Cornell University Press, Ithaca.

Darwin C., 1993 - The Correspondence of Charles Darwin. Volu¬

me 8: 1860. Cambridge University Press, Cambridge.

de Queiroz K., 1988 - Systematics and thè Darwinian revolution.

Philosophy of Science, East Lansing, 55: 238-259.

Flight C., 1988 - Bantu trees and some wider ramifications. Afri-

can Languages and Cultures, London, 1: 25-43.

Forbes W. A., 1882 - Report on thè anatomy of thè petrels (Tubi-

nares), collected during thè voyage of H. M. S. Challenger.

Zoology of thè Challenger Expedition, 11.

Ghiselin M. T., 1966 - On psychologism and thè logie of taxo-

nomic controversies. Systematic Zoology, Washington, D. C.,

15: 207-215.

Ghiselin M. T., 1974 - A radicai solution to thè species problem.

Systematic Zoology, Washington, D. C., 23: 536-544.

Ghiselin M. T., 1984 - The triumph of thè Darwinian Method.

University of Chicago Press, Chicago.

Ghiselin M. T., 1987 - Species concepts, individuality, and objec-

tivity. Biology and Philosophy, Dordrecht, 2: 127-143.

Griffiths G. C. D., 1974 - On thè foundations of biological syste¬

matics. Acta Biotheoretica, Leiden, 23: 85-131.

Haas M. A., 1966 - Historical linguistics and thè genetic relation-

ship of languages. Current Trends in Linguistics, The Hague,

3: 113-153.

Hoenigswald H. M., 1975 - Schleicher’s tree and its trunk. In: Ut

Videam: Contributions to an Understanding of Linguistics

(W. Abraham, ed.). Peter de Ridder Press, Lisse: 157-160.

Hoenigswald H. M., 1990 - Language families and subgroupings,

tree model and wave theory, and reconstruction of protolan-

guages. In: Research Guide on Language Change (E. C. Po-

lomé, ed.). Mouton de Gruyter, Berlin: 441-454.

Hoenigswald H. M. & Wiener L. F. (eds.), 1987 - Biological Me-

taphor and Cladistic Classifìcation: An Interdisciplinary Per-

spective. University of Pennsylvania Press, Philadelphia.

Holm G., 1972 - Cari Johan Schlyter and textual scholarship.

Saga och Sed, Uppsala, 1972: 48-80.

Hull D. L., 1975 - Central subjects and historical narratives.

History and Theory, Middletown, 14: 253-274.

Hull D. L., 1978 - A matter of individuality. Philosophy of Scien¬

ce, East Lansing, 45: 335-360.

Huxley T. H., 1868 - On thè classifìcation and distribution of thè

Alectoromorphae and Heteromorphae. Proceedings of thè Zoo¬

logica! Society of London, 1868: 294-319.

Johnes A. J., 1843 - Philological Proofs of thè Originai Unity and

Recent Origin of thè Human Race... Being an Inquiry How

Far thè DifTerences in thè Languages of thè Globe are

Referrible to Causes Now in Operation. Samuel Clarke,

London.

Jones W., 1786 - The third anniversary discourse. Asiatick Re-

searches, London, 1: 415-431.

Koerner E. F. K., 1981 - Schleichers EinfluB auf Haeckel: Schla-

glichter auf die wechselseitige Abhàngigkeit zwischen linguisti-

chen und biologischen Theorien in 19. Jahrhundert. Zeitschrift

fiir vergleichende Sprachforschung, Gòttingen, 95: 1-21.

Koerner E. F. K., 1982 - The Schleicherian paradigm in linguist¬

ics. General Linguistics, Binghamton, 22: 1-39.

Koerner E. F. K. (ed.), 1983 - Linguistics and Evolutionary

Theory: Three Essays by August Schleicher, Ernst Haeckel,

and William Bleek, with an Introduction by J. Peter Maher.

John Benjamins, Amsterdam.

Koerner E. F. K., 1987 - On Schleicher and trees. In: Biological

Metaphor and Cladistic Classifìcation: An Interdisciplinary

Perspective (H. M. Hoenigswald & L. F. Wiener, eds.). Uni¬

versity of Pennsylvania Press, Philadelphia: 109-113.

Lee A., 1989 - Numerical taxonomy revisited: John Griffìth, cla¬

distic analysis and St. Augustine’s Quaestiones in Heptateu-

chum. Studia Patristica, Berlin, 20: 24-32.

Lovejoy A. O., 1936 - The Great Chain of Being. Harvard Univer¬

sity Press, Cambridge.

Macleay W. S., 1819-21 - Horae Entomologicae: or Essays on thè

Annulose Animals. Bagster, London.

Maher J. P., 1966 - More on thè history of thè comparative me¬

thod: thè tradition of Darwinism in August Schleicher’s

work. Anthropological Linguistics, Bloomington, 8: 1-12.

Mayr E., 1982 - The Growth of Biological Thought. Harvard Uni¬

versity Press, Cambridge.

Minelli A., 1993 - Biological Systematics: The State of thè Art.

Chapman & Hall, London.

Mitchell P. C., 1901 - On thè intestinal tract of birds; with

remarks on thè valuation and nomenclature of zoological

characters. Transactions of thè Linnean Society of London,

Zoology, 8: 173-275.

Morpurgo Davies A., 1975 - Language classifìcation in thè nine¬

teenth century. Current Trends in Linguistics, The Hague, 13:

607-716.

Naumann B., Plank F. & Hofbauer G. (eds.), 1992 - Langu¬

age and Earth: Elective Affìnities Between thè Emerging

Sciences of Linguistics and Geology. John Benjamins,

Amsterdam.

O’Hara R. J., 1988a - Diagrammatic classifìcation of birds, 1819-

1901: views of thè naturai System in 19th-century British or-

nithology. In: Acta XIX Congressus Internationalis Ornitho-

logici (H. Ouellet, ed.). National Museum of Naturai Science,

Ottawa: 2746-2759.

O’Hara R. J., 1988b - Homage to Clio, or, toward an historical

philosophy for evolutionary biology. Systematic Zoology,

Washington, D. C., 37: 142-155.

O’Hara R. J., 1991 - Representations of thè naturai System in thè

nineteenth century. Biology and Philosophy, Dordrecht, 6:

255-274.

O’Hara R. J., 1993 - Systematic generalization, historical fate,

and thè species problem. Systematic Biology, Washington,

D. C., 42: 231-246.

O’Hara R. J. & Robinson P. M. W., 1993 - Computer assisted me-

thods of stemmatic analysis. Occasionai Papers of thè Canter¬

bury Tales Project, Oxford, 1: 53-74.

Oppenheimer J. M., 1987 - Haeckel’s variations on Darwin. In:

Biological Metaphor and Cladistic Classifìcation: An Inter-

disciplinary Perspective (H. M. Hoenigswald & L. F. Wiener,

eds.). University of Pennsylvania Press, Philadelphia: 123-135.

Pederson H., 1931 - The Discovery of Language: Linguistic

Science in thè Nineteenth Century. Harvard University Press,

Cambridge.

Priestly T. M. S., 1975 - Schleicher, Celakovsky, and thè family-

tree diagram: a puzzle in thè history of linguistics. Historio-

graphia Linguistica, Amsterdam, 2: 299-333.

Reif W.-E., 1983 - Hilgendorfs (1863) dissertation on thè Stein-

heim planorbids (Gastropoda, Miocene): thè development

of a phylogenetic research program for paleontology.

Palàontologische Zeitschrift, Stuttgart, 57: 7-20.

Reynolds L. D. (ed.), 1983 - Texts and Transmission: A survey of

thè Latin Classics. Oxford University Press, Oxford.

Robinson P. M. W., 1991 - An edition of Svipdagsmàl. Unpubli-

shed doctoral dissertation, University of Oxford.

Robinson P. M. W. & O’Hara R. J., 1992 - Report on thè Textual

Criticism Challenge 1991. Bryn Mawr Classical Review, Bryn

Mawr, 3: 331-337.

Robinson P. M. W. & O’Hara R. J. (in press) - Cladistic analysis

of an Old Norse manuscript tradition. Research in Humani-

ties Computing. Clarendon Press, Oxford.

Schleicher A., 1863 - Die Darwinsche Theorie un die Sprach-

wissenschaft. H. Bohlau, Weimar.

Stevens P. F., 1982 - Augustin Augier’s «Arbre Botanique»

(1801), a remarkable early botanical representation of thè na¬

turai System. Taxon, Utrecht, 32: 203-211.

Stevens P. F., 1984 - Metaphors and typology in thè development

of botanical systematics 1690-1960, or thè art of putting new

wine in old bottles. Taxon, Utrecht, 33: 169-211.

Stewart A. H., 1976 - Graphic Representation of Models in Lin¬

guistic Theory. Indiana University Press, Bloomington.

Strickand H. E., 1841 - On thè true method of discovering thè

naturai System in zoology and botany. Annals and Magazine

of Naturai History, 6: 184-194.

88

ROBERT J. O’HARA

Swainson W., 1836-37 - On thè Naturai History and Classifica-

tion of Birds. Longman, London.

Swofford D. L., 1991 - PAUP: Phylogenetic Analysis Using

Parsimony. Macintosh version 3. Or. Computer program

distributed by thè author, Smithsonian Institution, Wa¬

shington, D. C.

Timpanaro S., 1981 - La Genesi del Metodo del Lachmann, revi-

sed edition. Liviana, Padua.

Wallace A. R., 1856 - Attempts at a naturai arrangement of

birds. Annals and M agazine of Naturai History, London, 18:

193-216.

Whewell W., 1847 - The Philosophy of thè Inductive Sciences,

second edition. John W. Parker, London.

Zuckerman S. (ed.), 1976 - The Zoological Society of London,

1826-1976 and Beyond. Symposia of thè Zoological Society

of London. Academic Press, London, 40.

Robert J. O’Hara: Cornelia Strong College and Department of Biology, 100 Foust Building,

University of North Carolina at Greensboro, Greensboro, North Carolina 27412 U.S.A.

Systematic Biology as an Historical Science

Memorie della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano

Volume XXVII - Fascicolo I - 1996

Eugene Presnov & Valeria Isaeva

Topologica! classification: onto- and phylogenesis

Abstract — Here a topological approach is used for thè description and analysis of biological morphogenesis. Treating

biological structures as topological subjects results in a more adequate description of biological form dynamics than thè

traditional geometrical description, as topology studies thè most generai properties of spaces. Moreover, apart from ex-

tending of descriptional possibilities thè new methodology reveals a topological dependence and topological limitations of

biological morphogenesis. Traditional anatomical language is translated into a topological one. Principles and schematics

of topological classification of biological form dynamics in ontogenesis and evolution have been elaborated. An evolution-

ary pattern for thè topological shape of animals as well as a scheme for thè phylum Echinodermata is constructed.

“Dans la conception axiomatique, la mathématique appara it en somme comme un réservoir de formes

abstraites — les structures mathématiques; et il se trouve — sans qu’on sache bien pourquoi — que cer-

tains ascpects de la réalité expérimentale viennent se mouler en certaines de ces formes, comme par une

sorte de prédaption.

Il n’est pas niable déterminé; mai c’est précisement en les vidant volontairement de ce contenu qu’on a su

leur donner toute l’efficacité qu’elles portaient en puissance, et qu’on les a rendues susceptibles de rece-

voir des interprétations nouvelles, et de remplir pleinement leur róle élaborateur”.

L’Architecture de Mathématiques - N. Bourbaki, 1948.

For centuries mathematics and biology developed

almost independently, although an amazing regular-

ity of biological forms is undoubtedly related to a un-

itary harmony of thè world. In spite of this fact thè

importance of mathematics is not completely under-

stood by biologists, who sometimes reducine it to an

apparatus for statistical treatment of experimental

data. This inadequate perspective prevents one from

seeing thè farthest horizons of mathematical studies.

However, physicists realized a long time ago that

after thè development of an adequate model of any

physical phenomenon, i.e. a model enabling one to

do precise calculations and predictions, thè mathe¬

matical structure of thè model reveals new properties

of thè simulated phenomenon. Although it may

sound paradoxically, studies of inner mathematical

structure of thè model may alter our concepts of thè

reai process. This study also provides an extra proof

of thè well-known idea of N. Bourbaki that some as-

pects of experimental reality seem to fit some mathe¬

matical structures as if due to a kind of preadaptation.

This study shows that formulating known biological

notions using a new mathematical language relating

them to other concepts has some explanatory force.

The naturalists always devoted most of their acti-

vities to description and classification of objects of

study. Biologists developed a specific System to des-

cribe living forms and their transformations in deve¬

lopment, but in spite of common features of their

descriptions depend on personal interpretations not

having completely regular features. Biologists also

traditionally use geometrical language to describe

thè shape of organisms and cells, and thè dynamics

of form in ontogeny and evolution. However topolo¬

gical language is necessary and more adequate for

such description (Listing, 1847; Thompson, 1917;

Needham, 1936; Waddington, 1940; Raven, 1959;

Thom, 1969; Presnov, Isaeva, 1985; Isaeva, Presnov,

1990), since topology deals with thè most generai

properties of spaces as mathematical subjects. Mo¬

reover, topology enables us to analize a transition

from locai parameters to global ones; it is directly

connected to thè rather old embryologisf s idea con-

cerning an integration of parts and locai parameters

in an embryo (Driesch, 1894; Child, 194Ì; Wolpert,

1969). The spatial-temporal integration of individuai

development can be explained to a certain degree by

topological constraints controlling thè morphogenet-

ic processes in our physical space; topological pro¬

perties of thè space are reflected in topological form

dynamics during ontogeny. So w e can discuss thè to¬

pological determination of individuai development.

The topological description of morphogenetic pat-

terns in ontoqeny and phylogenesis is have propo-

sed, attempting to use mathematical terms strictly

describing various phenomena such as inhomoge-

neities, detuning processes and all process of esta-

blishing differences during development. For exam-

ple, thè developmental potential of thè ooplasm

clearly shows that it is not homogeneous object and

thè problem is not thè origin of this heterogeneity,

but also it retention and transformation in develop¬

ment. It appears that thè ooplasm’s inhomogeneities

are stable figures, representing topological mecha-

nisms that control morphogenesis.

To see how topological notions may apply to mor¬

phogenesis consider thè popular description of rub-

ber band with drawings of various configurations

upon its surface. Which parts of these confìgurations

would remain unchanged if one stretches thè rubber

in an arbitrary way without tearing it apart? Evident-

ly that thè size and thè values of angles and curvature

will vary (during such deformation) as they do in de¬

velopment and in evolution. But in thè topological

90

E. PRESNOV & V. ISAEVA

description of living systems we should also account

for thè topologically invariant characteristics. The

power of topology lies on operating on such proper-

ties in analytical form.

A translation of anatomy into topologica! language

The external shape of an organism, as thè shapes

of its organs and tissues, are modeled by smooth clo-

sed surfaces. The morphogenesis of most multicellu-

lar animals may be represented through topological

modification(s) of their epithelized surfaces. A layer

of epithelial cells is characterized by morphological

and functional connectivity, closeness of its surface

in thè intact organism and apical-basal (outer-inner)

anisotropy of thè cellular sheet. This allows to ne-

glect thè thickness of thè cellular layer, considering

epithelia as smooth, closed, oriented two-dimen-

sional surfaces. The connectivity of an epithelial

layer during epithelial morphogenesis (by folding

etc.) is ensured by thè System of specialized cell-to-

cell contact — fulfilling thè function of integration of

cells and their cytoskeletal systems into a united

morphological and functional entity. Through such

prerequisites one can develop a combinatorial

approach modeling thè morphogenesis of a whole

organism.

Let us apply a theorem of elementary topology

to thè spadai organization of epithelial layers: any

closed surface in three-dimensional space is homeo-

morphic to a sphere with a given number (p) of han-

dles. The sphere with p handles sets a class of ho-

meomorphic surfaces of thè genus p. So long as there

are no topological surgeries (breakings and glueings)

of epithelial sheets thè genus of thè surface p is a

topological invariant and any detailed geometry

(curvature of surface, angle values) is not essential.

According to thè proved theorem thè closed surfaces

of thè genus

p = 0, p = 1, p = 2,

give a full topological classifìcation. An example of

such a surface is thè sphere to which p handles are at-

tached. Usually thè topological handles in biological

objects are represented «through channels» such as

thè digestive tube, i. e. — any through channel or

hole in an organism is topologically equivalent to

handle. Then topological morphogenesis in thè de-

velopment of a living organism (as in evolution) is

given by series of topological modification {surgeries)

of closed surface. For example, thè surface of an egg,

thè outer surface of blastula or early gastrula as well

as thè bodily surface of an adult coelenterate are sur¬

faces of genus 0, that is homeomorphic to a sphere.

The epithelial surface of an embryo or a larva with a

through intestine tube (having both orai and anal

openings) such as thè outer surface of an annelid or

nematode worm is a surface of genus 1, topologically

equivalent to a sphere with one handle attached or to

a torus (Figure 1).

Fig. 1 - Topological models of biological shapes. Left column:

stages in thè development of sea urchin: egg, blastula, larva, defi¬

nitive shape. Right column: 3-dimensional ball, 2-dimensional

sphere (genus 0), torus (genus 1), closed surface of genus 2.

Viewing topologically thè digestive tube is an

outer surface of an organism is unusual for biolo-

gists 0). The contents of thè digestive tract are un-

doubtedly part of thè external mediun flowing

through an organism; thè intestine epithelium is a

boundary tissue — between thè internai medium of

an organism and thè outside medium; epithelial cells

function as bordering, absorbing and conditioning

thè external medium elements.

The bodily surface an organism with one through

channel besides thè digestive tube is a surface of

genus 2, topologically equivalent to a sphere with

two handles.

Through channels of thè respiratory System are

also fìlled with an external medium, so that thè sur¬

face of thè respiratory System too may be considered

as outer surface of an animai. Coelomic cavities

opening outside by coelomoducts with unidirection-

al flow of coelomic fluid from thè cavity are physio-

logically better, but not completely, isolated from

thè external medium; thè content of coelomic fluid

in marine annelids, mollusks and echinoderms is

similar to that of marine water. In generai thè epi¬

thelial surface of an organism having n through

channels is homeomorphic to thè sphere with n

handles — i.e. is thè translation of anatomy into topo¬

logical language.

(') According to Prof. A. Minelli’s opinion, in some parts of biology this notion is well accepted: in parasitology thè ca-

tegory of parasites living in thè gut is clearly separated from thè category of thè true endoparasites living within thè tissues.

TOPOLOGICAL CLASSIFICATION: ONTO- AND PHYLOGENESIS

91

Topological modifìcations of epithelial surfaces

in ontogenesis

“Digestive channel, arterial System (including thè heart), thè centrai

nervous System (including brain) appear as simple tubular struc-

tures. The nature machines them as a glassblower”.

On Growth and Form - D’Arcy Thompson, 1917.

During development in most animals thè surface

of an organism, say, an epithelial envelope of an or-

ganism, undergoes topological modification or se-

quential modifìcations (surgeries) of thè closed sur¬

face, changing thè topological genus of this surface,

except for those in which thè definitive state is a

genus 0 surface (coelenterates, fìat worms). As in hi-

gher animals thè epithelial surface of an embryo or

larva with a through intestine tube is a surface of

genus 1 (torus) during development thè genus of thè

surface (so called «spherical surgery») is inevitably

transformed: (p = 0) (p = 1). This transformation is

a transition from a blind archenteron to a through in¬

testine tube and is usually realized at thè gastrula

stage of development by means of an appearance of

another opening opposite thè blastopore; thè blasto-

pore (or primary mouth) will be thè definitive orai

opening in Protostomia or anal opening in Deuteros-

tomia. So thè through intestina! tube arises by thè

break through of thè mouth opening (in Deuterosto-

mia) or one anal opening (in Protostomia) into thè

blind archenteron.

Animals having surface of genus 1 as adults (for

instance, round and annelid worms) undergo in on¬

togenesis only thè transformation from sphere to

torus:

(p = 0) -> (p = 1).

The ontogenesis of animals with thè genus of outer

surface 2 (echinoderms and mollusks - see below)

inevitably undergo two transformations:

(P = 0) - (p = 1) - (p = 2).

In other of protostomions and deuterostomions with

higher order adult state thè surface genus 1 + 2 n (see

below) thè following transformations take place:

O = 0)^(/? = l)^(/? = l + In).

Thus during embryogenesis thè surface of an orga¬

nism undergoes sequential topological (i.e. spheri¬

cal) surgeries, changing thè topological genus of

their surface. These surgeries are locai phenomena,

whereas its genus is a global characteristic. Topologi¬

cal surgeries changing thè connectivity of germ (em-

bryonic) layers are also possible; different types of

topological surgeries modifying spatial organization

of epithelial sheets in ontogenesis have been descri-

bed earlier (Presnov, Isaeva, 1985). Topological mo-

dification of thè connectivity of germ layers results in

a separation of additional closed spherical surfaces

from preexisting ones, for example during neurula-

tion in chordates. Spatial organization of thè orga¬

nism of an evolutionary advanced animai may be

represented topologically as an outer epithelial enve¬

lope (or shell) of certain genus p embracing a numer

of inner closed epithelial surfaces, that are embed-

ded inside thè outer envelope. However thè modifi-

cations of connectivity do not change thè topological

pattern of this outer surface shell (Figure 2).

Fig. 2 - Modifìcations (surgery) of topology during embryonic

pattern formation. Left column: locai aspect of surgeries; Right

column: global aspects of surgeries. <p0, q>] - surgeries. A(p0 — orai

piate rupture; Acp, — obliteration of branchial clefts; B<p0 — obli-

teration of choroid fissure; Bq), — separation of somites from

splanchnotome; C<p0 — mouth breaking into blind archenteron;

C<p, — neurulation; D(p0 — fusion of two heart anlagen, forma¬

tion of a single body cavity when thè sheets of lateral piate fuse;

D<p, — enterocoel mode of thè formation of thè mesoderm.

The topological surgeries in epirhelial sheets be-

come realized locally at thè cellular level; cellular

mechanisms of thè epithelial are sheet disintegra¬

tion, celi migration, celi adhesion and epithelization,

but any topological surgery always is global topologi¬

cal modification of biological form.

Evolution of topological forms

Plant organisms as a rule do not have any obligate

through channel; all thè variety of forms in thè plant

kingdom is created by pure geometrical complication

without topological modifìcations (2). Although

there are various perforations of plant body in some

species, most plants have thè genus of thè surface

equal to zero (p — 0). The topological form poverty

and rigidity in plants probably is restricted on thè cel¬

lular level by immobility and fixed position of cells

and cellular associations.

(2) For example, thè stornata of higher plants may open into common cavities, but these parenchymal cavities are irre-

gular and not epithelized. We consider as topological handles only epithelized through channels.

92

E. PRESNOV & V. ISAEVA

In thè animai kingdom, however, celi mobility,

specific celi adhesion and morphogenetic celi death

ensure thè creation, destruction and variability of su-

pracellular associations as a topological variety of

form in evolution.

The analysis of topological modifìcations of thè

closed epithelial layers covering thè outer surface

«envelope» of a developing organism (formed both

by thè external epithelium and by thè intestinal epi-

thelium too) is also applicable to consideration of to¬

pological organisation of thè bodily surface in evolu¬

tion. And here also thè topological modifìcations

changing thè genus of thè surface are important as

modifìcations of connecticity don’t change topologi¬

cal pattern of bodily surface.

The most primitive of recent multicellular ani-

mais, Placozoa, have a surface of thè body without

any through epithelized channels that is homeo-

morphic to sphere.

Poriferes have numerous channels penetrating all

thè body and connecting thè spongocoel and choa-

nocyte chambers with thè external medium. From

thè topological point of view thè genus of thè surface

in sponges is indefinite and extremely high. Such a

peculiarity in topological organization of Porifera

confirms thè data and conclusions of comparative

morphology on sponges as a special branch in animai

kingdom.

Coelenterates (Cnidaria) and fiat worms (Turbel-

laria) are characterizing in ground pian by a blind

intestine which is opened by a mouth functioning

also as an anus. As any blind invagination do not

change thè topological genus of thè surface, its

value is 0 too. Thus thè form of above types of

animals did not proceed above thè level of a sphere

(p = 0) although in separate representatives of these

types numerous evolutionary attempts to acquire

anal opening and consequently thè through intestine

have been observed: thè sole pore of hydra, pore

channels of intestine in some Turbellaria, intestine

pores of actinia, pores of thè circular channel in

some jellyfìshes. None of these openings are homo-

logous to thè anal opening of higher Bilateria. Few

representatives of fìat worms have one or several

anal pores.

The appearance of a through gut, instead of a blind

one is a topological modification of great evolution¬

ary importance, since thè external medium flows

through it resulting in better utilization and condi-

tioning of thè medium, and better digestion and ab-

sorption of its elements.

In animals of many taxa thè gut is thè only any

other through channel. The differentiation of many

organ systems proceeds through blind, often branch-

ing, invaginations, obviously giving various possibili-

ties for thè evolution of organ System. Mollusks and

echinoderms have achieved a next stage of topologi¬

cal organization of thè surface since, besides thè di¬

gestive System, they also have a second through

channel due to increased integration of thè coelomic

System. In mollusks thè through channel opening

outside via two coelomoducts and coelomopores re-

sults from thè fusion in to one (of pair of coeloms).

Most echinoderms exhibit a second through chan¬

nel due to presence of ambulacral ring channel open¬

ing outside by one canal (see below). Such pattern of

ambulacral System is topologically homeomorphic to

torus of sphere with one handle.

Thus biological evolution in mollusks and echino¬

derms results in a second through channel, but this

way of topological modification seems to lead thè

evolution into a dead end, it is not used by higher re¬

presentatives of Protostomia or Deuterostomia ani-

mais developing another System of through chan¬

nels. The next level of topological organization in

thè animai kingdom is achieved due to development

of through channels of thè respiratory System: tra-

cheal System in higher terrestrial arthropods (3) and

gill clefts in chordates. The System of paired tracheal

tubules connected laterally (in arthropods) or thè

System of through paired branchial clefts (in chorda¬

tes) results in a surface, which in topological terms

is homeomorphic to thè sphere v/ith 2n handles,

i.e. having thè genus 2 n ( n is number of respiratory

openings).

The creation of through respiratory System is thè

topological modification of thè bodily surface which

results in better utilization of oxygen from outside

medium (air or water) flowing through thè organism,

conditioning of thè medium flow and more intensive

metabolism; it can be considered as thè next step in

evolution. The acquisition of thè through respiratory

System correlates with thè development of thè most

advanced morphological and functional organization

— among protostomes in insects, among denterosto-

mes in chordates.

Thus a parallelism of topological and functional

modifìcations in evolution of both protostomes and

deuterostomes is obvious: a transition from thè

sphere in thè topological sense (p = 0), that is an or¬

ganism without a digestive cavity or with a blind gut,

to a tube or in topological terms thè torus (P= 1), an

organism with through digestive tract, and subsequ-

ent transition from thè torus by adding an even

amount of channels (handles) of thè respiratory Sys¬

tem to thè surface of genus p = 1 + 2n. The acquisi¬

tion of thè surface of thè genus 2 may be considered

as a blind branch in evolution both Protostomia and

Deuterostomia. The evolution of thè topological

form of thè surface in animai kingdom may be short-

ly expressed in thè following summing up schemat-

ics (see also Figure 3):

p = 1 + 2n

p = 2 t

\t

P = 1

t

p = 0 -»• p = N

The generai similarity or even identity of evolu¬

tionary and ontogenetic form modifìcations makes it

possible for us to develop a unifìed topological classi-

fication of biological forms.

( ) l'here are lateral connections or anastomoses between tracheomeres in some Diplopoda and Araneina. In most

insect tracheal tubes are connected by a System of lateral and transversai channels (Beklemishev, 1964).

TOPOLOGICAL CLASSIFICATION: ONTO- AND PHYLOGENESIS

93

Fig. 3 - Schematics of evolution of topologica! forms of animals.

A topological classification based

on embryonic forai dynamics

Although thè trend of increasing thè genus of sur-

face and thè amount of isolated layers in onto- and

phylogenesis is obvious, modifìcations decreasing

both thè genus of epithelial surface and thè amount

of closed isolated epithelial layers sometimes occurs

in onto- and phylogenesis. Hence thè time ordering

of modifìcations should be also taken into account.

Since thè topological modifìcation (surgery) is cano¬

nicali related to thè hole of thè surface, we will

order thè holes (through channels, or handles) and

mark them by C, . The Symbol C, acquires either thè

value of 0 or 1 depending on thè absence or presence

of j- th fundamental hole. After that thè set

I (Q , c2, . . . , cn)

will correspond to any organism. It is clear that thè

dynamics of above set (word) in animal’s ontogen¬

esi would be more complete than thè resulting

genus of thè outer surface

P = Cx + C2 + . . . + C^r

— classifying characteristics. The usuai dynamics of

variation of coding word in thè majority of animals is

(0) - (1).

However, in animals with embryonic envelopes or

specialized larvae, for instance in thè annelid worm

Polygordius we have thè follo wing scheme:

(0) -> (1) -+ (0) - (1).

During embryogenesis of Peripatopsis capensis (Ony-

chophora) an amazing bifurcation can be observed:

(0) - (1,1,1) - (0) - (1).

This mathematical approach to describing of deve-

lopmental phenomena is convenient and simple; it

enables us to give thè detailed classification of recent

echinoderms.

Scheme for thè phylum Echinodermata

The topological genus of thè bodily surface of an

echinoderm is equal to 2 for thè ground pian with

through gut and circular ambulacral System opening

outside through an additional channel. Now we will

take into account also another through epithelized

holes appearing and vanishing during embryogen¬

esis. We will consider and distinguish thè functional

value of each through channel. Thereby, we have at

hand four types of channels:

gut, ambulacral System, hydropore, waterpores.

The numerical characteristic: Cx corresponds to

absence (0) or presence (1) of thè through gut. C2 — to

absence (0) or presence (C2 > 0) of circular ambula¬

cral System opening into outside medium by one (1)

or more (C2 > 1) channels; (C2 > 1) also corresponds

to presence of anastomoses connecting two rings of

thè ambulacral System in Concentricycloidea medusi-

formes (4). C3 corresponds to thè presence of connec¬

tion of hydropore with thè outer medium by one

simple hole (1) or through madrepore piate with

multiply pores (C3 > 1). C4 designates thè presence

(C4 > 0) of thè pores of thè sea lily cup.

During planctonotrophic type of development of

sea urchins, starfìshes, ophiurans and holothurians

thè genus of thè surface of their larvae is p — Cx = 1

(presence of through gut). In cases of lecitotrophia

no through channels are observed prior to metamor-

phosis in these animals or in crinoids. During meta-

morphosis thè through digestive tract vanishes tem-

porarily in planctotrophic larvae. The development

of ring channel of thè ambulacral System opening

outside only through thè stony channel (in sea ur¬

chins, starfìshes, ophiurids, some holothuria) or

through five channels (in sea lilies) provides thè

topological genus of thè bodily surface to be equal

to p = C2 — 1 or p = C2 = 5 respectively. In thè defini¬

tive state thè most echinoderms have a through gut

(Cx = 1), but Concentricycloidea, Ophiuroidea and

some Asteroidea are exclusive ( Cx = 0). Most echi¬

noderms exhibit a connection of thè ambulacral

System with thè outer medium through multiple ma-

dreporite pores (C3 > 0); only in sea lilies is there a

(4) Concenticycloidea (whose only thè representative is Xyloplax medusiformes ) may be regarded as a class (Rowe et

al., 1988) but other evolutionary systematics prefer to treat X. merusiformes as highly specialized Asteroidea. Here we

represent Concentricycloidea as a separate class (or a separate group of lower rank) of Echinodermata.

I

94

E. PRESNOV & V. ISAEVA

System of numerous acqueous pores through thè cup

surface (C4 > 0) (Figure 4).

Using thè System of ontogenetic variations thè

change of classifying word:

(Q, C2 , C3, C4)

and definitive values composing its letters we plotted

a scheme for six classes of recent echinoderms with

thè following sequence (see also Figure 5):

c=(cnC2‘CJ'C*) / p=LCi

Fig. 4 - Topological schematics of ontogenesis in echinoderms.

Column I: embryogenesis; Column II: metamorphosis; Co-

lumn III: definite state.

f Crinoidea -► Concentricycloidea -► Holothuroidea —

( Asteroidea-* Ophiuroidea-’* Echinoidea.

Fig. 5 - Scheme of echinoderms using topological parameters.

The similarity between this topological classifica-

tion and legitimate zoological classifìcations proves

thè naturality of such topological approach which ad-

ditionally is quite simple.

Thus thè analysis of topological form dynamics in

ontogenesis may provide additional possibilities in

cladistic analysis although thè construction of a

given scheme based on pure topological characters is

only an experiment, as in cladistics many different

characters besides thè topological ones should be

taken in account.

Generally thè topological approach gives a new

adequate and strict language for description and clas-

sifìcation of biological forms and their dynamics in

embryogenesis and evolution.

Acknowledgments — Best thanks are due to thè or-

ganizers of thè workshop (Michael T. Ghiselin, Gio¬

vanni Pinna and Francesco M. Scudo) for inviting

one of us (E. P.) to attend this meeting and also

for thè discussion of this paper by all participants.

We are very indebted to M. Ghiselin, A. Minelli,

F. Scudo and C. Urbani for helpful comments by

letters. M. Ghiselin and F. Scudo also corrected our

English.

REFERENCES

Beklemishev I. N., 1987 - Basics of Comparative Anatomy of

Invertebrates. Nauka, Moscow, Voi. 1. 431 pp.; Voi. 2. 445 pp.

(In Russian).

Bourbaki N., 1948 - L’architecture de mathématiques. In: Les

Grands Courants de la Pensée Mathématiques. Cahiers du

Sud: 35-47.

Child C. M., 1941 - Patterns and Problems of Development. Uni¬

versity of Chicago Press, Chicago, 811 pp.

Driesch H., 1894 - Analytische Theorie der Organischen Ent-

wicklung. Verlag von Engelmann, Leipzig, 184 SS.

Isaeva V. V. and Presnov E. V., 1990 - Topological Structure of

Morphogenetic Fields. Nauka, Moscow, 256 pp. (In Russian).

Listing Ì. B., 1847 - Vorstudien zur topologie. In: Gòttingen Stu-

dien. Universitàt Gòttingen, Gòttingen: 811-875.

Needham J., 1936 - Order and Life. Cambridge University Press,

Cambridge: 175 pp.

Presnov E. V. and Isaeva V. V., 1985 - Modifications of Topolo-

gy in Morphogenesis. Nauka, Moscow: 191 pp. (In Russian).

Raven C. P., 1959 - An Outline of Developmental Physiology.

Pergamon Press, Oxford, 232 pp.

Rowe F. W. E., Baker A. N. and Clarke H. E. S., 1988 - The

morphology, development and taxonomic status of Xylopax

Baker, Rowe and Clark (1986) (echinodermata: Concentricy¬

cloidea), with thè description of a new species. Proceedings of

thè Royal Society of London, SeriesB,233 (1273): 431-459, plates 1-7.

Thom R., 1969 - Topological models in biology. Topology, 8 (3): 313-335.

Thompson d’Arcy W., 1917 - On Growth and Form. Cambridge

University Press, Cambridge, lst edition, 794 pp.

Waddington C. H., 1940 - Organisers and Genes. Cambridge

University Press, Cambridge, 160 pp.

Wolpert L., 1969 - Positional information and thè spadai pattern of

cellular differentiation. Journal of Theoretical Biology, 25 (1): 1-47.

E. Presnov & V. Isaeva: Dep. of Appi. Math. & Comp. Se., The Weizmann Inst. of Se., Rehovot 76100, ISRAEL

Lab. of Embr., The Inst. of Mar. Biol., Russian Academy of Science, Vladivostok, 690041, RUSSIA

E. Presnov - Present address: Habsor Experimental Station, Negev 4, ISRAEL

Systematic Biology as an Historical Science

Memorie della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano

Volume XXVII - Fascicolo I - 1996

Francesco M. Scudo

Symbiosis, thè origins of major life forms and systematics:

a review with speculations

«It is often said that all thè conditions for thè fìrst production of a living organism are now present,

which could ever have been present. But if (and oh what a big if) we could conceive in some little

pond, with all sort of ammonia and phosphatic salts, light, heat, electricity, etc., present, that a pro-

tein compound was chemically formed ready to undergo stili more complex changes, at present day

such matter would be instantly devoured, or absorbed, which would not have been thè case before

living creatures were formed». C. R. Darwin, as in F. Darwin (1887), Voi. II: 202.

Abstract — It is difficult to explain thè origin of prokaryotes proper other than through symbioses among «uncoded»

proteinoids, on which viruses eventually flourished. Cellular coding would thus have started as a symbiotic enterprise of

very diverse virai elements, in which a large variety of codes were at fìrst established in order to prey upon, or parasitize

quite diverse proteinoid cells. Prokaryotes proper might have accasionaly merged into chimaers, and so apparently did

more complex cells closer to eukaryotes. Nuclear structures proper appear to be of late, multiple and possibly symbiotic

origins, connected with regular alternations between thè haploid and thè diploid cellular phase. These low eukaryotes then

acquired diverse endosymbiotes, mostly bacterial, which they permanently retainod as organelles; some of them quite like-

ly originated from distinct symbiotic events, involving much thè same symbiont. A common triplet code was eventually es¬

tablished among thè metazoans and thè metaphytes. Their cellular specializations were made possible by thè gender diffe-

rentiation of thè haplophases, that took place in many eukaryotic lineages in a few standard forms. In higher metaphytes

and seemingly all extant metazoans this haploid gender specialization was then replaced by true hermaphroditism, in tura

often resulting in diploid gender. The metazoans continued to form dose, physiologically specialized symbioses with

algae, fungi and bacteria. A common outcome of bacterial symbioses consistei in transferring to thè host’s genome some

relevant functions of thè symbiont, that was then discarded as such. Analogous, radicai transformations induced by much

thè same symbiont on rather difìferent metazoan stocks could have rendered them far more similar, as quite likely happe-

ned for thè Hyrudinea, thè Pogonophora and thè Blattoidea, possibly thè Cirripedia etc.. Directly «genotypical» symbioses

with viruses also remained common especially among thè higher animals, whose genomes largely consist of repeated, mo¬

bile elements of virai origin. Traditional systematic practices are not well suited to deal with these modes of often multiple

origins.

This review deals with theories on origins of major

life forms in order to explore possible connections

among them and implications for systematics. § 1 will

start by touching upon a few examples of reconstruc-

tions with restricted aims, mention some of thè con-

straints or problems that ought to be taken into ac-

count and fìnally consider a few treatments aiming at

completeness. Based on these treatments, § 2 will

sketch a sequence of connected scenarios for thè ori¬

gins of thè prokaryotes, thè protists, thè metazoans

and metaphytes (§ 2). § 3 will then examine thè very

different «tempos and modes» of evolution these

scenarios imply, and some of their direct consequen-

ces for systematics. More generai problems in syste¬

matics are approached in thè Final Remarks from an

historical perspective, also as a way to justify some

theoretical premises.

The term «symbiosis» is now being employed with

two radically different meanings. The recent mean-

ing, now comon, is to denote any dose, often endo-

cellular association, most of which are clearly patho-

genic. Symbiosis is, intended here in thè traditional

sense, to denote bodily associations that are obliga-

tory at least under given conditions, and take place in

standardized rather than erratically varying ways. By

being standardized, any such association is assumed

*

to benefit at last thè «host» even if thè precise nature

of thè benefìts is not known. A qualification of sym¬

bioses as «mutualistic» is problematic in many cases,

of animals in particular (cf. e. g. Nardon et al. 1990).

Most well understood forms of dose symbiosis in

animals clearly point, in fact, to a parasitic or preda-

tory fìrst origin, that only involves mutualism in any

proper sense as intermediate evolutionary stages.

Although common, hereditary associations are not a

necessary prerequisite for highly specialized, obliga-

tory symbioses. Thus thè luminescent symbiotes of

many cephalopodans are highly specialized forms of

«wild» photobacteria that remain «extracellular»,

and are obtained by thè host at each generation by

infection from free living ones (cf. Pierantoni, 1923,

Ruby & McFall-Ngai, 1992).

It is worth anticipating major differences in thè

symbiogenesis of taxa that clearly affect thè very

foundations of systematics. The principles and goals

of taxonomy and phylogeny mainly stem from com¬

parative anatomy of thè vertebrates and other deute-

rostomians proper. These easily establish full ge-

nomic integrations with viruses but only rarely dose

symbioses with bacteria or fungi, and only in special

cases these have major consequences at macroscopic

levels. On thè other hand metakaryotic protists are

96

FRANCESCO M. SCUDO

essentially qualified by thè nature of their symbioses

with different microorganisms. In most metazoans

other than deuterostomias algal, fungal and bacterial

symbioses are relatively common, and most have

major irreversible consequences also at macroscopic

levels (e. g. Nardon et al., 1993). As a result, different

stocks of most eukaryotes can be rendered more si-

milar by establishing symbiotic bonds with thè same

microorganism. Ampie parallelisms, or convergen-

cies also arise among thè metakaryotes from very si-

milar forms of sexual differentiation. As one turns to

prokaryotes thè quest for common ancestry might

prove even more elusive if, as it seems these origi-

nated through innumerable symbioses among

previously «free» proteic components and, then,

nucleic ones.

1) On theories and problems

a) «Popular» theories about origins

Only in thè 1920’s Oparin and Haldane managed to

turn thè problem of origins into a socially acceptable

topic for discourse. Till thè late 1950’s this mainly

consisted in generai arguments for thè origins of

simple life forms from non-living Earth materials,

carried on as if hardly anything was known on thè

functions of their different Chemical components. By

thè late 1950’s it had become clear that DNA was in-

deed thè «universal» carrier of inheritance, as Mies-

cher had claimed nearly a century earlier. Further,

«soups» believed to reflect prebiotic conditions were

shown to easily produce proteinoids akin to proteins

and smaller amounts of simpler biological com-

pounds. Molecular biology then clarifìed many

aspects of life components and of their interac-

tions, among which reverse transcription and thè

enzymatic and «editing» properties of RNAs are of

special relevance to first origins (cf. § 2 a).

Most theories on first origins that are directly

based on molecular knowledge concentrate on one

of thè major components of life — usually RNA or

proteins — as if it had a near absolute primacy over

other components whose origins are hardly explai-

ned. How coding carne about is thè centrai problem

to which very diverse Solutions are offered — e. g.

earliest life having been coded by some clay entities,

and only much later reai genes having «taken over»

(Cairns-Smith, e. g. 1985). Assuming that RNA carne

first seems to be a satisfactory way out of «chicken

and egg» problems, but only in vitro. Thus it seems

impossible to obtain thè nucleotides, thè building

blocks of nucleic acids, through abiotic synthesis. On

thè other hand «proteins» can easily phosphorylate

nucleosides to nucleotides, and simple sugars are

«robustly» produced abiotically as are thè bases (far

more so purines than pirimidines (e. g. Miller, 1993).

Even if thè building blocks of RNA could have been

produced abiotically, their assemblage does not ap-

pear likely other than through surface catalysis. Then

to energize this assembly, while sparing thè final pro-

duct from thè disrupting effects of thè same energy,

only seems possible if RNA’s had an extraordinary

tendency to dive as soon as «born». It is even harder

to imagine how these RNA’s could have survived

«on their own», cells being their only known and

reasonable-looking support. On thè other hand com-

binatorics would not be much of a problem by rea-

soning on an «RNA World» in terms of Wright’s

«shifting balance theory» (e. g. 1970, cf. § 2 a) on very

numerous «species» of biomolecules (cf. Eigen, 1987,

apparently unaware of thè extent his reasoning over-

lapped with Wright’s).

Life having started with membranes might seem

an easy alternative to an RNA primacy as these can

easily self-assemble in proper conditions also in thè

form of «microspheres», capable of selective osmosis

and doubling, or fusing. This alternative too is often

phrased in exclusivistic tones such as thè Genesis-

mocking «In thè Beginning was thè Membrane» (Ha-

rold, 1986: 168), while not any more complete, or

convincing than an «RNA World». Stili another way

out of concentration and energizing problems would

be for life-components having started in bubbles. As

both bubbles and wet surfaces are common around

ponds, some among thè innumerable steps of pre-

cellular life might well have taken place in either of

these ways.

All along there had also been deep analyses of one

or another aspect of origins, with very reasonable

answers it considered separately. Thus thè theory ac-

cording to which viruses would have originated from

RNA molecules ecaping thè control of cells looks as

reasonable as its main alternative — i. e. that they

carne about «alongside with thè molecules of life»

(in fact thè former is a precondition to thè latter in

thè scenario of § 2 a). There are, however, astronomi-

cal numbers of combinations and permutations of

thè answers for all thè steps involved, among which

it is hard to make meaningful connections and even

harder to choose. Thus both «compartimentaliza-

tion» theory of eukaryotic organelles and that of vi¬

ruses as «degenerate» prokaryotes might seem rea¬

sonable on their own, but it is hard to make sense of

both other than by assuming that thè metakaryotes

come first, and thè prokaryotes carne from desym-

biotyzed organelles. A major premise of thè present

analysis is that problems of polarity — i. e. a given

process appearing about as reasonable as its reverse

one — are less likely to arise thè larger thè set of orga-

nisms, or events being considered.

b) Some among thè many «facts» a complete theory

ought to take into account

Recent, explosive increases in factual knowledge

added very different «constraints» to theories on ori¬

gins, most of which concentrate on bringing about a

reasonable prokaryotic «progenote» or on interpret-

ing eukaryotic organelles as symbioses with proka¬

ryotes. Some among thè most surprising and appa¬

rently more binding such constraints concern timing

and physical conditions, to which only rarely sufflc-

ient attention has been paid.

For instance it has been firmly established that at

least thè inner planets originated by stochastic accre-

tion of discrete bodies (e. g. Dones and Tremaine

1993) — i. e. «planetesimals» that are occasionally

«doublé» or comets that could land in one piece or,

more likely, break up preceeding impact. Further,

though it is not yet clear how, or why, thè Earth

achieved an orbite very dose to thè present one

about four billion years ago (e. g. Milani 1988) - i. e.

only shortly before thè first cells appeared. The lon-

ger thè Earth kept to much thè same orbit thè better

SYMBIOSIS, THE ORIGINS OF MAJOR LIFE FORMS ANS SYSTEMATICS

97

it «sweptin» any respectably sized body with which it

was likely to collide. Collisions, in fact, might have

been a primary mechanism responsible of well spa-

ced planetary orbits, with periods far from resonan-

ce, out of more chaotic initial ones (Scudo 1993).

Such «accretions» must have had far larger direct

physical effects on thè atmosphere and dry land than

on thè whole Oceanie masses, and stili larger indirect

effects as through accumulations of snow and ice

and their subsequent melting. These physical chan-

ges would have mainly affected thè more complex

forms of animai life, resulting in thè simultaneous,

global extinction of many animals while plants

would get by more easily through spores, or seeds.

Then thè transformations of life are not, or not only

thè nearly continuous processes in which many be-

lieved, and in which some continue believing in spite

of all thè evidence to thè contrary. Rather, many life

forms were suddenly destroyed at times, and each

time new «normal» life arrangements carne about by

re-associating in different ways thè survivors, some

of which were drastically changed (cf. § 3 c).

The fossil record thus produced shows that proka-

ryotic-like cells existed for about 2 billion years with

hardly a major recorded change. Eukaryotic-looking

cells likewise persisted for a quarter to half that long

with hardly any noticeable change, before rapidly

giving rise to most animai phyla and thè early green

land plants (cf. Fedonkin, these proceedings). Any

reasonably complete theory on origins must then ac-

count for these two long periods of stasis, during

which disturbancies of cosmic origin were more fre-

quent and substantial than later on.

Furthermore, any theory aiming at completeness

ought to also account for «puzzles» such as thè sub¬

stantial variabilities in Chemical composition of

DNAs and in codes among viruses, and thè far lesser

ones among thè prokaryotes and thè lowest eukaryo-

tes. Virology treatises usually justify DNA’s Chemi¬

cal variability as a defense from bacterial restriction

enzymes, and some DNA variants might indeed

have this function. On thè other hand, to my know-

ledge, no sound reason has been given as to why this

justifìcation would also apply to Bacillus, viruses

having only uracil DNA. If life had indeed started

from a coding «progenote», among other things

it would be hard to justify thè variability in DNA

composition and codes among prokaryotes and low

protists.

c) On theories aiming at completeness

Only very few theories on origins aim at complete¬

ness and none of them has, or has ever had much fol-

lowing. The oldest such theory by Giglio-Tos (main¬

ly 1900 to 1910) is also by far thè most complete,

though it deals with thè basic features of life only in a

simplifìed way — i. e. much as gravity explains thè

features of rivers. The amount of labour involved in

drawing from gravity any detailed inference about

specifìc problems concerning rivers gives a good idea

of thè lack of detail in Giglio-Tos’ theory, which in

turn justifies its standing up in terms of present-day

knowledge. Thus GT deals with large combinations

of biomolecules, thè biomores, without specifying

their Chemical nature or spatial arrangements and

just distinguishing between «somatic» and «genetic»

ones. Life would have started with very simple mole-

cules capable of doubling by transforming different

Chemicals from a primevai broth, as well as of chang-

ing and transmitting their changes. As suitable bio¬

molecules thus carne about, «symbioses» among

them would have given rise to simple biomores.

Then different, suffìciently advanced biomores

would have been forced to associate symbiotycally

into simple protocells or biomonades; more advan¬

ced biomonades would have then specialized their

biomores into somatic and genetic ones, as in proka¬

ryotes and organelles. Then nucleated cells would

have arisen by symbiotic associations of different,

genetically specialized biomonades, as Mereschows-

ky and others had already proposed (e. g. Khakina,

1979).

Much as it was for Darwin and followers such as

Moebius and Cuénot, for GT any form of life under

«normal» conditions was, as it stili is, bound to oth¬

ers by interactions that often have substantial mu-

tualistic components. Should a parasitic or predatory

bond persist long enough undisturbed, among suit¬

able organisms, it would tend to become an «indisso-

luble» symbiosis. One among GT’s most originai

achievements was a relatively complete theory on

thè relationships between sexual reproduction and

development — i. e. gender would be thè pillar of thè

mechanisms through which vegetative cells can dif-

ferentiate genotypically, and thus allow for thè ex-

tended «symbioses» of multicellularity. As this theo¬

ry incurred in a gross, hardly avoidable «mistake»

(Scudo 1994) I shall here consider it in an amended

form (§ 2, c), confining its topological features to thè

Final Remarks.

Only recently have there been reasonably comple¬

te attempts to show how life components could origi¬

nate in thè «naturai» order of increasing complexity

of their synthesis — i. e. «proteins» first, nucleic acids

last, fatty acids and sugars in-between. Though full

of «it is far from obvious how. . .», Folsome (1979) is

noteworthy by starting from a reasonable protocell

not yet coded for; however he gets around thè noto-

rious combinatorial problems through random but

exceedingly small biomolecules, such as 5 to 7 ami-

noacid peptides. The remarkable enzymatic and «be-

havioural» properties of RNA’s were discovered

mostly later (cf. Symons 1992), radically changing thè

rules of thè game.

The stale «chicken-egg business» alluded to in a)

was set in motion again by two remarkable works:

Cordón (1990) and de Duve (1991). Different as they

are in many respeets, these concur with Folsome in

assuming that veritable «proteic» cells — rather than

just proteinoid membranes — carne about before any

cellular coding proper. So far, Cordón’s pubblished

treatments have arrived at thè simplest such cells

that are stili open, vase-like, made up by a layer of

proteic beings of a single kind that grow much as do

thè germinai lines of volvocales or thè pyrosomes,

with a lipidic layer on thè inside. He painstakingly

explains why such heterotrophic colonies, saprophy-

tes of autotrophic ones, were forced to evolve verit¬

able cellular behaviours (1990, Voi. 1) and then he ex-

amines thè early phylogeny of biochemical cycles

(1990, Voi. 2, cf. also Scudo 1992a). De Duve’s theo-

retical preferences are analogous to Cordón’s on

many counts, to thè notable exception of cells be-

coming closed very early, thus making it hard to ex-

plain thè origin of viruses except than by «degenera-

98

FRANCESCO M. SCUDO

tion» (cf. § 2a). The sequence of tentative scenarios

that follows is liberally based on thè treatments by

Giglio-Tos, Cordón and de Deuve, aiming to ac-

count for «facts» as in b) above.

2) Some «complete» scenarios for origins

a) The rise of thè cells and thè «genetic takeover»

The precise nature of thè earliest, «Chemical»

steps of life remains to a degree conjectural since thè

initial composition of thè atmosphere is stili an open

problem (e. g. Kasting 1993). These steps themselves

are not problematic, however, since even very simple

Chemical systems share with present-day life thè

basic features of self-duplication, «mutation» and

«selection» (e. g. Hong et al., 1992), and different life

components are synthetized abiotically in a wide va-

riety of conditions (cf. § 1 a). I am thus sketching here

a plausible sequence of events starting from diverse

proteinoids, primarily globular enzymes, associated

in complex systems or, more precisely, biogeocoeno-

ses. These relatively complex, non-coded «free pro-

teins» would have been error prone in reproducing,

which is hardly problematic since plenty of sequence

variations have only minor effects on function, and

all reproduced about as inefficiently. Some such pro-

teic being would form different types of «colonies»

including heterotrophic, open «cells» like Cordón’s

(cf. § 1 c), which would provide a basis for symbiotic

associations with other, non-colonial «proteic» beings.

According to Cordón thè above process would

have reached a turning point when thè coenzymes in

a celi type included thè building blocks of present-

day RNA, or alike compounds no longer found in it.

Some short «Ur-RNAs» capable of relatively error-

free replication would have formed easily, at fìrst

with no function other than storage-transport. Then

these Ur-RNAs would have then developed other

useful functions, such as repair of proteic compo¬

nents or physical support for their production. The

physiologies of these Ur-RNAs might have then be-

come akin to thè stili poorly known ones of viroids

and virusoids. By being easily transmissible among

thè stili open cells, some such Ur-viroids would have

spread from their native celi types to others as mild

predators-parasites, suited to acquire all kinds of

symbiotic functions.

As cells thus kept increasing in complexity, thè

next turning point would have consisted in some vi¬

roids starting to build capsids out of cellular aminoa-

cids, thus developping primitive codes and larger

chromosomes. The greater power of dispersal and

more complex physiology thus achieved would have

allowed them to be really virulent on some hosts.

Greater dispersal would also have resulted in more

horizontal exchanges among different virai stocks

tending to homogenize their RNAs, quite likely ini-

tially variable also in Chemical composition. Some

celi types would have reacted to ever increasing

parasitic loads by closing up, thus accelerating thè

symbiotic adjustment of thè entrapped «viruses».

Ohnishi (e. g. 1990) provides direct evidences for

coding having originated as a collective, symbiotic

entreprise of distinct RNA organisms.

Alongside thè above process some viruses would

have started to «prey upon» RNA components more

efTiciently by differentiating forms of nucleic acids

for thè sole purpose of replicating their chromoso¬

mes, namely into Ur-DNAs. The uracil DNA of thè

Bacillus, viruses might represent an obvious step in

this process which, by taking place near-indepen-

dently in different virai and celi lineages, would have

resulted in DNAs chemically far more variable than

those now extant. In this scenario many, possibly all

variants in DNA Chemical composition would be

remnants of this initial variability rather than modifì-

cations of an originally homogeneous DNA, in part

retained by assuming functions such as defense from

restriction enzymes. Notice how thè two major theo-

ries of virai origin usually presented as alterna¬

tive (cf. § 1, a) here become complementary — i. e.

RNA molecules that «escaped thè control of cells»

would have been thè starting point in thè evolution

of coding.

From a variety of coding mechanisms and DNAs,

mastered by symbionts-parasites of cells, further

evolution of coding would have been a biocoenotic

process at a stili more extended, more collective

level. Any one virai lineage could undergo direct ge¬

netic exchanges with others and it would be subject-

ed to diverse selective pressures also from different

host cells, in which it quite likely played different

roles. Any such virus, originally parasitic on a celi

type, could have slowly turned into its symbiote and

then be incorporated into its chromosome, perhaps

with quite different functions than in other celi

types. Somewhere along these processes of symbiot¬

ic specialization, thè establishment of reverse trans-

criptases would have made coding easier also for

proteic components proper of cells. Cellular coding

might thus have started by «copying» proteic compo¬

nents into messenger RNAs and then retrotranscribe

them to DNA, as proposed by de Duve (1991). «Ge¬

netic take over» of Chemical information in any one

celi type would have soon resulted in a single «main»

chromosome, as thè only manageable reproductive

arrangement.

In turn, establishing a single cellular chromosome

opened thè way to a complete, effìcient «genetic

take-over» as in thè extant eukaryotes. For long this

might have been a major adaptive goal among cells

that no longer shared, or exchanged coding func¬

tions to thè extent they did while stili open — i. e.

they did so only occasionali through new virai sym-

biotes as plasmids or sexual processes. Quite likely

symbioses between prokaryotic lineages also took

place rarely, such as between a poorly motile and a

highly motile one, and thè chromosomes of thè

«partners» soon merged. The extant variability in thè

Chemical composition of DNAs and in codes among

viruses and prokaryotes would then reflect thè level

of homogeneization achieved at thè outset of euka-

ryotic evolution, as further reduced by differential

extinction. These processes would have taken place

through much thè same selective effects of thè

struggle for life as in thè «biogeocoenoses» of multi-

cellular ornanisms — i. e. involving both selection

and chance, both within and among populations

(cf. Wright, e. g. 1970 and § 3 c).

Quite likely code homogenizing only resumed

on a wide collective basis in thè evolution of thè

metakaryotes. DNA and coding uniformity thus

eventually resulted among thè metazoans and thè

metaphytes, whose chromosome complements are

SYMBIOSIS, THE ORIGINS OF MAJOR LIFE FORMS ANS SYSTEMATICS

99

made up in substantial proportions by repeated, mo¬

bile «virai» elements.

b) The origin of thè eukaryotes

The eukaryotes are characterized by their cytos-

keletons, by mostly very similar chromatin arran-

gements and by a variety of nuclear organizations

— i. e. micronuclei, macronuclei and nuclei proper,

with different modes of division. The higher ones

(Metakaryotes or S80) also posess a variety of orga-

nelles not found in thè lower ones (Archeozoans or

S70). Reasonably detailed reconstructions tend to

agree on basic issues in thè evolution of thè thè Ar-

chezoans (e. g. de Duve 1990, Cavalier-Smith 1990)

and on distinctive metakaryotic organelles — notably

ribosomes, plastids and peroxisomes — having origi-

nated from symbioses with prokaryotes.

Far from clear, on thè other hand, are origins of

microtubule-associated motors such as in thè axone-

mes of cilia and flagella, in mitotic and meiotic spin-

dles and other processes of mechanical transport.

These microtubules and motors might all be due to

much thè same machinery of symbiotic origin, as

suggested by direct biochemical or structural evi-

dence (e. g. Margulis et al. 1990) as well as by many

eukaryotes «reabsorbing» their cilia or flagella dur-

ing celi division. This might contrast with many rea-

sons why thè evolution of thè S70’s would not have

been accompanied by any symbiotic event (Cavalier-

Smith 1990). Further, reasonable explanations for

thè origins of microtubules and their associated mo¬

tors might also quite directly account for a number

of eukariotic taxa lacking cilia and flagella, or having

flagella only in thè sperm.

A satisfactory explanation of all these evidences

might thus be far more complex than often assumed

— e. g. thè «inner» motor machineries of eukaryotes

having originated from a symbiotic event prior to thè

evolution of most other S70 features, while thè meta¬

karyotic cilia and flagella originated from different

symbiotic events with prokaryotes lacking dose,

known relatives. It is hard to choose among many

plausible reconstructions of such events so long as

thè biochemical evidence is stili as incomplete as at

present (e. g. Walker and Sheetz 1993), end detailed

ultrastructural evidences are stili scattered (e. g. En¬

gelhardt et al. 1993).

All eukaryotes seem to have primitively undergo-

ne an alternation between a haploid and a diploid

cellular phase, stili retained in different forms by

most of them.

In many protists thè diplont is dormant and highly

protected, carrying thè population through adverse

conditions and then giving rise to four haplonts. The

syngamic processes through which two haploid cells

produce thè zygote or analogous set-up (dicaryonts

in fungi, diplokaryonts in microsporidians, e. g. Can-

ning 1988) are mediated by very different adapta-

tions. In many low protists syngamy is achieved by

haplonts of uniform size (isogamy) through sequen-

tial modifications of their behaviours — e. g. aggluti-

nating as a start. Their most primitive sexual speciali-

zations consist in many genotypic differences called

poles, each pole favouring syngamy with a different

one. In more advanced forms syngamy within thè

same polarity is altogether prevented with various

consequences — e. g. only one of thè uniting cells

passes on a given organelle (cf. e. g. Hurst and

Hamilton 1992). The most avanced forms of these

evolutionary sequences consist of only two poles

(bipolarity).

In a few low protists, however, syngamy takes

place among cells that do not appear to have any

polarity differentiation but widely differ by size in a

continuum. Here syngamy always occurs between

two cells with at least some size difference, thè smal-

ler one distinctively behaving «as male», thè larger

one «as female» (relative sexuality).

Except in some of their lowest representatives, thè

gametic phase of thè metakaryotes is specialized into

sperm and egg cells (spermatic nuclei, oospheres); in

many forms without cilia or flagella, such as red

algae and nematods, sperm and egg cells are dose in

size. These specializations, collectivively denoted as

oogamy, often look very similar. They apparently

evolved innumerable times among unicellular pro¬

tists, often directly deriving from bipolarity — i. e.

one of thè poles splits into four or eight smaller cells

just prior to syngamy while thè other looses its fla-

gellum(a) (e. g. Bacci, 1965).

On thè other hand it is far from clear whether, and

in which cases, oogamy directly evolved from rela¬

tive sexuality, altogether bypassing isogamy and po¬

larity (e. g. Scudo 1973, cf. also further evidence from

Iriconympha).

From its distribution, oogamy appears being an es-

sential precondition for thè diplophase to become

substantially dominant over thè haplophase in multi-

cellular eukaryotes. Thus most if not all algae fìrst

evolved multicellularity in «identical» forms in thè

two phases, thè diplophase slowly becoming domin¬

ant only after becoming oogamous. This dominance

reaches extremes, as in thè Fucales, where thè spores

are retained on thè mother diplont, soon entering ga-

metogenesis. At variance from algae, in green land

plants a substantial dominance of thè diplophase was

only achieved after a marked cellular differentiation,

as in ferns.

On thè other hand it seems that most, if not all thè

ancestors of metazoans had developped multicellu¬

larity from thè outset only in thè diplophase, alto¬

gether lacking an independent haplophase (cf. e. g.

Scudo 1973).

The operation of naturai selection seems to justify

in a simple, generai way that all organisms with a do¬

minant diplophase are oogamous. It is easily shown

(Haldane 1924, Scudo 1975) that individuai selection

for a genetic variant operates on a sexually undiffe-

rentiated haplophase «about» twice as strongly as in

thè diplophase. This statement roughly describes thè

results of approximate analytical models showing

that selective contests about dominance are strongly

biased in favour of a sexually undifferentiated haplo¬

phase. On thè other hand, in thè same contests a va¬

riant affecting only one haplont gender would «play

about even» with one affecting thè diplophase. The

gender differentiation of thè gametes can obviously

provide various direct advantaged besides those to

be examined below, such as size dimorphism to easi¬

ly result in more efficient unions in demanding cir-

cumstances (Scudo 1967). Since a low gametic di¬

morphism is far from rare both among protists and

animals — even higher ones such as some crusta-

ceans (Baccetti, e. g. 1985) - it is not per se indicative

of gender specialization.

100

FRANCESCO M. SCUDO

c) Gender, development and thè origins of thè

metazoans and thè metaphytes

As hypotesized by Giglio-Tos (cf. § 1, c) thè most

primitive, generai function of gender would be to

allow cellular specializations also other than sexual

— i. e. «epigenetic» modifications in ontogeny could

only revert to a state dose to thè initial, zygotic one

through syngamy between gametes of different gen¬

der, or amphimixis. Cellular specializations could

only evolve through such epigenetic modifications

though these might no longer be necessary for deve¬

lopment at subsequent stages. Here different parti-

cularizations of these assumptions — now supported

by direct evidences such as methylation, including

sexual imprinting in thè vertebrates, cf. e. g. Jablon-

ka et al. (1992), Jablonka (1994) - shall be explored

through direct evidences and plausible inferences on

mechanisms. To this end, first recali how haploid,

gametic gender always appears being under strict

control of constitutive genomic differences — i. e. a

major diallelic or an heterochromosomal segregation

in all known instances of bipolarity, anisogamy and

oogamy. At least in some bipolar forms — e. g. Schi-

zosaccharomyces pombae (Arcangioli 1992) — revers-

ible gender marking or «imprinting» is also evident

at thè level of chromatids, rather than at that of whole

haploid genomes as in some diploid systems.

In hermaphroditic metazoans either sperm or eggs

are usually produced usually in different parts of thè

body, or at different times, as is also thè case for mo-

noecious Bryophytes and for micro and macrospores

in monoecious metaphytes — i. e. all these forms

lack segregational mechanisms for gametic or sporal

gender.

Diploid gender consists in individuate being spe-

cialized to produce different proportions of sexually

differentiated gametes, or spores, up to complete se-

parations of these sexes or gonochorism in animate.

These specializations too are usually connected

somehow to constitutive genomic differentiations,

though in no known case they appear to be strictly de-

termined by a single mechanism.

Thus «environmental» sex determinations of me¬

tazoans ateo have, as a rule, at least some hereditary

variability for thè threshold of response to thè gen-

der-triggering stimulus. In thè classic case of Bonellia

viridis, for instance, most larvae exposed to a mature

female settle on her as parasites thus becoming

males; if not so exposed they settle on thè ground,

becoming females. A small proportion of larvae, ho-

wever, are «true males» that never settle on thè

ground, and soon die if unable to find a female host

(cf. Bacci 1965). To thè partial exception of heteroch-

romosomes, thè effects of dialleic mechanisms for

gonochorism are subjected to all kinds of modifica¬

tions by external conditions, as for producing inter-

sexes or reversate of thè genotypic sex according to

temperature or age of thè egg at fertilization. As a

rule gonochorisms through heterochromosomes are

far less dependant upon conditions of growth as far

as thè «primary» sexual phenotype is concerned,

while thè whole sex phenotype often remains sub-

stantially «plastic». In thè latter case whole haploid

genomes are often epigenetically gender-marked, as

for sperm imprinting in mammals. At least in hu-

mans thè differential utilization of thè paternal and

of thè maternal complemens in ontogeny has been

directly, macroscopically evident since long (e. g.

Weismann 1904).

On thè other hand a strict determinism of thè

whole sex phenotype seems only possible through a

complex balance between thè heterochromosomes

and autosomal loci, acting in different ways through

their maternal and syngamic (zygotic) effects (e. g.

Cline 1993). It is thus safe to infer some generai, ne¬

cessary links between gender differentiation and me¬

chanisms of epigenetic inheritance, regardless of

whether known at thè molecular level, that explored

as an Appendix.

3) Systematics and thè diverse «tempos and modes»

in evolution

The scenarios of § 2, a) are analyzed here in terms

of traditional and symbiotic phylogenetics, with refe-

rence to data such as introduced in § 1, b). As both

such phylogenetics substantially differ from contem-

porary usages (cf. e. g. Minelli, these proceedings), it

will be useful to first recali their basic principles and

terminology. In traditional phylogenetics an assemb-

lage of lineages that originated from some common

ancestor constitutes a taxon. This is qualifìed by a set

of characters or character combinations at a given

epoch, and it is said to be monophyletic if thè com¬

mon ancestor belongs to thè taxon as so qualifìed.

Unless meant to imply that a taxon is artifìcial, in tra¬

ditional phylogenetics thè term «polyphyletic» is

usually accompanied by some restrictive qualifìca-

tion — e. g. «thè modem reptiles are likewise defìnite-

ly polyphyletic» (Schmalhausen 1968: 289, my em-

phasis).

In symbiogenetic systematics, on thè other hand,

as a rule a taxon is qualifìed by thè establishment of

an obligatory symbiosis. If this symbiosis originates

only once between given representatives of two taxa,

thè symbiogenetic definition of thè taxon coincides

with thè phylogenetic one. However a taxon, say C,

symbiogenetic of A an B (A U B), often originates at

distinct places or times, through distinct representa¬

tives af A and B, say Al U Bl, Al U B2, Al U B3 etc.,

as due to some common external pressures on A and

B such as an «infectious» spread of thè symbiote. If

such a taxon is suffìciently distinctive — or so is just

thè symbiote as for chloroplasts — its multiple ori¬

gins by no means imply that it should be regarded as

artifìcial.

These prescriptions straightforwardly apply to

dose algal, fungal and bacterial symbioses, all of

which have been infrequent, lasted very long as such

and always had major, irreversible consequences

(cf. e. g. Pierantoni 1923, Buchner 1965, Smith &

Douglas 1987 and thè Final Remarks). On thè other

hand attempting to strictly apply thè same rule to

other symbioses could make systematics «imposs-

ible» — e. g. virai symbioses in thè metazoans where

they are frequent and can easily differ within a Lin-

nean species, or thè same virai genome might be

shared by thè nuclear complements of very distant

species. Here thè traditional prescriptions of sym¬

biogenetic systematics will be followed only to thè

extent they would not force giving up major, esta-

blished taxonomic terminology or generai, useful

canons in systematics (cf. Simonetta, these pro¬

ceedings).

SYMBIOSIS, THE ORIGINS OF MAJOR LIFE FORMS ANS SYSTEMATICS

101

a) On prokaryotes and their origins

Should thè scenario in § 2, a) be anywhere dose to

truth it would necessarily imply that thè prokaryotes

and organelles are intrinsecally, highly polyphyletic,

to an extent which is not easy to ascertain. These

would in fact represent any number of lineages

— most likely not just very few — out of innumerable

lineages of non-coding cells, as originated by distinct

symbiotic events. Coding would also result from

very many symbiotic events, at times involving dif-

ferent coding agents with analogous functions. Fur-

ther, in thè process of homogenizing codes and

DNA’s among protocells, some proteic component

could have been easily transferred from a lineage to

another, or any two lineages might have symbiotical-

ly fused, and thus be misleading about proteic ances-

try in ways that are hard to disintricate.

Turning to thè tempo of pre-cellular and cellular

evolution, notice how thè scenario in § 2, a) easily

justifies a fast rise of cells looking prokaryotic in thè

record, while only partially coded or not at all. Then

thè near-stasis of such cells for about two billion

years (Ga) would be mostly an apparent one, corres-

ponding to thè evolution of cellular coding. Such an

early establishment of cells would have been poss-

ible since biochemical evolution took place quite ra-

pidly up to thè establishment of free-living protei-

noid entities, mainly since these had very short life

spans. Further, thè evolution of free protenoids was

most likely ruled by thè fast Chemical changes in a

medium stili very far away from its near-equilibrium, as

eventually reached mainly through photosynthesis.

This changing Chemical composition would have im-

posed strict conditions only on thè functions of cata-

lytic agents, quite regardless of their precise struc-

tures or sequences.

Due to thè generally scarce sequence specificity of

thè early, free-living proteinoids, naturai selection

would have been rather ineffìcient on them. Selec¬

tion would also have had slow and with relatively

loose effects on colonies of proteinoids and on non-

coded cells, since these were likely to have some-

what more precise forms of reproduction than free

proteinoids, but their life spans would be far longer.

Early cellular evolution would also have been slower

than «free» proteic one by being mostly caused by

Chemical changes life was producing, and these tend-

ed to occur at a slower pace than earlier. Further,

early cellular evolution quite likely took place

through collapses of complex, previously established

biocoenoses of different celi types, to be replaced by

novel ones. Previously, it was rather thè matter of

Chemical cycles being modified by a novel enzyme

which got established, more often than not just

changing thè status of some old one rather than eli-

minating it (see agaion, Cordón 1990, Voi. 2 and de

Duve 1991). During early cellular evolution thè stili

substantial and frequent impacts (cf. § 1, b and c

below) could easily heat up most of thè Oceanie mas-

ses and evaporate part of them without resulting in

major, global extinctions of simple, hardy proteic

beings, widely distributed and highly variable. Then

cellular evolution might have been so slow also, or

mainly since it was not speeded up by sudden mass

extinctions of exogenous causation.

Even a primitive, partial coding of cells would

have allowed naturai selection to achieve far stricter

results than on non coding ones. Coding, however, is

not likely to have much speeded up cellular evolu-

tion, since selection would operate upon more com¬

plex, longer living cells. Most likely early prokaryotes

were even less sensitive to physical conditions of life

than their extant representatives (cf. Fedonkin, these

proceedings) so that extinctions among them would

stili be mostly caused by thè ever slower Chemical

changes they produced, notably oxygen accumula-

tion, No wonder, then, that it might have taken

about two Ga for protocells to master coding mecha-

nisms. Incidentali, infering parentage among proka¬

ryotes and organelles through components of their

coding machineries might well mislead as to their

ancestral proteic parentage. Thus thè evident diphy-

lety in thè rRNAs of modern Gram positives (van de

Peer et al., 1994) might well reflect an ancient phylet-

ic divergence after these had become established or,

rather, an originali diphyletic, symbiotic establish¬

ment of rRNAs.

Il prokaryotes and organelles had indeed all diver-

sifìed from a coding «progenote» it would be hard to

explain haw this could have evolved in very few hun-

dred million years, or why its descendants so much

differentiated their codes and also thè chemistry of

their DNAs before giving rise to thè eukaryotes. Ra¬

ther, thè notion of a progenote might just derive by

applying thè «normal» assumption of monophyly to

thè origin of cells where it would just pose severe,

most likely spurious problems — e. g. thè evolution

of chromosomes as dealt with by Eigen (e. g. 1987)

through a precarious balance between «hypercycles»

and «compartments». Much current theoretical lite-

rature is struggling for better Solutions to this pro-

blem that does not arise in thè scenario of § 2 a) just

because, as a rule, any one «viroid» had to «fìt» into

different cells through somewhat different means.

b) Symbiosis and thè evolution of thè Eukaryotes

As pointed out in § 2, b) thè eukaryotes share some

basic biochemistry, cytoskeletal features and some

sorts of nuclei. Among thè lower ones even DNA

composition, codes and chromatin organization are

stili quite variable (cf. e. g. Rizzo, 1991 for thè dino-

flagellates), suggesting that also their nuclei might

have had multiple origins. Much thè same might well

apply to thè presence versus absence of cilia or fla¬

gella, as a primitive feature probably connected to

thè evolution of nuclear division (cf. § 2 b, if unicellu¬

lar, thè haplophase could be spared from this loss).

Regardless of thè precise extent to which thè meta-

karyotes might be regarded as «ancestrally polyphy¬

letic» their organelles might have more different ori¬

gins than directly evident — i. e. «thè same» organelle

might have had multiple origins — as apparently thè

case for chloroplasts (e. g. Cavalier-Smith, 1990).

Also a variety of endocellular symbiotes appear to

have levels of integration akin to organelles while de-

parting from them for their more restricted localiza-

tions, as for thè Gram negatives that are essential for

thè survival of all cockroaches.

The peculiar «epixenosomes» of thè cibate Euplo-

tidium itoi but for lacking a nucleus have all thè ap-

pearence of microsporidians (Rosati et al., 1993) and

thus support thè view that nuclei were multiple ac-

quisitions, rather likely late ones through symbioses.

Though somewhat controversial (see again Fedon-

102

FRANCESCO M. SCUDO

kin, these proceedings), thè fossil record points to

thè eukaryotes not showing major, recorded innova-

tions for about one Ga prior to rapidly giving rise to

most or all metazoan phyla. Then this «stasis» too

could well agree with thè reasoning in § 2, c) in being

just an apparent one, corresponding to thè symbiotic

origins of thè nuclei, then of thè metakaryotes and to

thè evolution of their haploid sexual specializations.

If analogy with bryophytes and lycopods applies

(cf. thè Appendix) thè originai haplont sex System

might have been homogenized in a number of vascu-

lar stocks while keeping thè haplophase dioecious. If

so, thè metaphytes might stili be regarded as mono-

phyletic in thè sense of originating from related Cha-

rales stocks. The metazoans too are likely to derive

from distinct homogeneizations of thè haploid sex

System in multicellular stocks but, as far as one

knows, they might well be polyphyletic in thè more

basic sense of having had rather different, unicellular

protistan ancestors. More detailed knowledge of cel-

lular components and distinctive motory organelles,

such as thè «missile-type», might reveal such ancient

parentages, so far elusive.

In principle thè problem of single versus multiple

symbiotic origins might be more precisely approa-

ched for metazoan taxa, as in thè classic example of

roaches, termites and mantids that stili remains con-

troversial (cf. e. g. Handlirsch 1908, Grassé and Noi-

rot 1959, Buchner 1965, Scudo et al., MS). The same

problem seems more easily amenable to a precise so¬

lution for thè pogonophorans, since this «phylum» is

represented by two rather diverse taxa, thè Vesti¬

mentifera and thè Perviata, each of which is rather

homogeneous. While solely known through Perviata

adults, pogonophorans were regarded as deuterosto-

mians of uncertain affìnities, having unique features

such as an apparent digestion through tentacles (e. g.

Becklemishev, 1969, 1: 394). The quite different vesti-

mentiferan juveniles confirm thè dose affìnity of po¬

gonophorans to anellids, already maintained by Li-

vanov and Porfirieva (cf. Becklemishev, 1969, II: 214).

Their main difference from anellids is evidently due

to thè bacterial symbiotes filling, and much enlarg-

ing thè cells of their guts (e. g. Smith & Douglas

1987) — i. e. in thè smaller Perviata this has a much

reduced lumen, which appears being altogether eli-

minated in thè Vestimentifera. The distinctive po-

gonophoran traits thus seem having separately ori-

ginated in two anellid stocks, by moving to unusual

habitats where both domesticated thè same sulfìde

oxidizing bacterion. The relationships among thè

Vestimentifera, thè Perviata and their anellid an¬

cestors are stili far from clear, however, since they

share «telling» traits both with polychaetes and oli-

gochaetes (e. g. thè axonemic structure of thè sperm,

cf. Baccetti 1985).

c) On extinctions, plant and animai evolution and

their physical causes

The metazoans and thè metaphytes appeared

when thè physical conditions on Earth were already

fairly dose to thè present ones. An atmosphere with

much thè same Chemical composition as now was un-

dergoing regular weather fluctuations, to which there

were superimposed erratic glacial periods, occasionai

bursts ol tectonic activity and thè effects of impacts,

progressively more rare and smaller on average (cf. §

1, b). As individuate, metazoans and metaphytes tend

to be more sensitive than protists to physical condi¬

tions of life (cf. Fedonkin, these proceedings) though

often able to resist short term disturbances in terms

of propagation, as through resting eggs and seeds.

A far more precise fossil record than for protists

(cf. again Fedonkin) shows that, especially among

animate, major rediations tended to follow mass ex¬

tinctions, some of which are sudden or have large

«instantaneous» components.

Much recent evidence points to boundaries bet-

ween eras and lesser epochs as often coinciding in

time with, and somehow be caused by major impacts

(cf. § 1, b). Such would be thè multiple ones on thè

southern tip of thè Gondwana (Gondwana II) corres¬

ponding to hardly separable craters over a thousand

miles radius in South Africa and South America.

This was quite likely due to a comet breaking into

several pieces prior to impacting, though thè pieces

migh thave acted mechanically as a «single impact»

causing thè Gondwana to break up. While impacts

leave hardly questionable signatures such as micro-

tektites and nanodiamont sprays, many objections

keep being risen against their causative roles on

«coincident» border extinctions. These objections

largely stem from considering only thè direct effects

of impacts — i. e. tsunamis, fìres, atmospheric cool-

ing and acid rain from dust — as well as from reason¬

ing on species rather than on biocoenoses (cf.

below). Less direct interpretations of impact effects,

much as in Vernadky’s tradition, can easily turn such

objections into revealing insights on less direct

modes of action. Thus consider glaciations, that

hardly fit Milankowitch’s otherwise excellent predic-

tions of climatic periodicities, and seem to be best in-

terpreted as thè result of uplifting tendencies and

their subsequent reversai by glacial accumulation

(Kostitzin 1934, ateo in Scudo and Ziegler, 1978). Let

us briefly see how this mechanism could easily

«magnify» thè effects of impacts (Scudo 1993a).

In a non-glacial epoch, cooling due to thè dust of a

large impact is likely to result in a rapid, massive ac¬

cumulation of snow, perhaps too short-lasting to

turn into true glaciers. As temperature climbs back

to normal, this snowmass melts quite rapidly, even if

melting is not speeded up by thè subsidences it

might cause. During glacial accumulation, cooling

from an impact could easily reverse an uplift stili

under way, or much speed up a subsidence that had

just started. Jointly with thè warming up that follows,

thè meltdowns of preexisting glaciers and of thè rec¬

ent snow accumulations would thus be much faster

and massive than «normally», and nearly synchroni-

zed. Needless to stress how thè effects of such ano-

malous snow-ice accumulations — their very rapid

melting in particular — are likely to be far more de¬

vastatine for many organisms, in many habitats, than

thè cooling that caused them. The K-T boundary ap¬

pears to well fìt this kind of reasoning by correspond¬

ing to a relatively modest impact — though probably

much terger than previously thought, namely a crater

about 300 kilometers in diameter (Sharpton et al.,

1993) — preceeded by two-three million years of unu-

sually strong telluric activities such as thè Deccan ba¬

sate floods (Basu et al., 1993).

The interactions between cosmic and terrestrial

processes are stili poorly understood in generai, save

perhaps for thè effects of major early impacts on thè

SYMBIOSIS, THE ORIGINS OF MAJOR LIFE FORMS ANS SYSTEMATICS

103

atmosphere (cf. again Kasting, 1993). Whichever

their causes, however, thè Earth surely underwent

numerous, sudden catastrophic changes (e. g. Ager

1993) and one should try to understand how and why

these affected evolution. To begin with, notice how

thè characteristic forms of biocoenoses tend to all

be exceedingly persistent in thè absence of major

disturbances, while any sufficiently global distur-

bance tends to jointly eliminate most such forms

(large, specialized animals in particular). The col-

lapse of any one «harmonic fauna», then, is primari-

ly related to its complexity and specialization,

much in thè same sense that a complex machine is

more likely to either work well or not at all than a

simpler one. No wonder, that thè prominent, highly

specialized components of rich, long established

faunas tend to either persist or disappear jointly, as

can be easily realized also a priori through mathe-

matical models such as Volterra’s (cf. Scudo and

Ziegler 1978).

Such extinctions might thus easily include whole,

long established taxa, particularly of large, speciali¬

zed, compulsorily cross-breeding animals that can-

not change fast, if at all, nor survive in small patches

or at low densities (cf. thè «limited variability» wi-

thin taxa in thè Final Remarks). The reverse also

holds in such conditions — i. e. animals that are

smallish, phenotypically plastic etc. will all tend to

rapidly change to some degree. At thè extreme, a suf¬

ficiently «plastic» lineage forced to colonize a new,

nearly desertic habitat, might give rise to «hopeful

monsters» that can survive by having no enemies,

and are more likely to enter new symbioses than in

normal conditions. The «wrong» genes of these

monsters can be subjected to directional individuai

selections of intensities that are not possible other-

wise (e. g. Haldane 1953). Stili more relevant, per-

haps, through a partially stochastic operation selec-

tion within populations can be faster and «cheaper»

than in mass conditions, and result in a substantial

selection among populations that magnifies and

spreads far more «creative» results (Wright, e. g.

1970). Thus improved upon, «lucky monsters» might

soon be able to withstand thè modest competition

from poorly adapted outsiders that would start mov-

ing in.

As a possible example consider barnacles, as as-

sessed by Darwin to represent different stocks relat¬

ed in ways he did not succeed ascertaining, nor did

others later on (cf. Ghiselin, these proceedings). It

was recently suggested (Alessandrello et al. 1992,

Scudo 1993) that barnacles derive from sandy bottom

crustaceans related to thylacocephalans, rather than

directly from pelagic crustaceans as Darwin had pro-

posed. If so, of their two «metamorphoses» (e. g.

Darwin 1851: 103) — both quite likely caused by sud¬

den changes in sea level — thè one to pupa would re¬

present thè switch to sandy bottom growth resulting

in «thylacocephalans», thè one to adult thè final

switch to a solid substratum. Each such switch of

substratum might have renderd more alike diverse

lineages ancestral to barnacles, as well documented in

other cases (cf. b above and thè Final Remarks). Then

bamacle ancestry might be so difficult to untangle due

to their multiple origins as dwellers of hard bottoms,

possibly of soft ones as well. Incidentally if Darwin

(e. g. 1851: 12) was correct in assessing thè cement as

being thè same adaptation in all, very different bar¬

nacles, and a unique one, this striking coincidence

might well be justified by distinct symbiotic origins

in ancestral lineages, involving thè same microorga-

nism (cf. again thè Final Remarks for well documented

cases).

Final remarks

Many points in this review depart from current fa-

shions and, to lesser degrees, also from more fìrmly

established positions. So far tentative phyletic re-

constructions were justified mostly through plain

common sense as for «viruses» and thè evolution

of coding — i. e. being thè simplest organisms with

coding machineries akin to «higher» ones, most likely

viruses played a centrai role in their origin. Here I

shall allude to a sample of theoretical foundations

that were mostly subsumed so far, in thè guise of an

historical sketch of systematics, that emphasizes thè

tensions between common practices and infering thè

history of fife.

One might well start with Lamarck, according to

whom discovering «thè order of production of living

beings» should be thè «first and foremost task» of a

Zoologica 1 Philosophy, as quite distinct from improv-

ing upon Linnaeus’ «magnificent construction». To

thè former end he relied on organs and organ Sys¬

tems by ranking them according to their generai util¬

ity and to their modes of utilization by «higher»

forms. However Lamarck did not go far in his main

task; rather he kept having excruciating doubts on

thè actual rankings of organs and systems (cf. e. g.

Vachon et al ., 1972: 258-263). Darwin entered evolu-

tionary systematics by posing thè problem of rela-

tionships in thè far more ambitious terms of «reai

parentage» among species much as in a family tree —

i. e. ideally in terms of a concrete measure such as

generations. For him too this goal would be quite

distinct from more practical purposes such as identi-

fication, to be achieved by diverse means (cf. his cor-

respondence with Waterhouse, recently pubblished

in full). Both Lamarck and Darwin presented their

phyletic reconstructions through trees, Darwin’s best

known ones (in Origin, its only illustration) being

very bushy. Having three to six branches at most

nodes well fìts a minor novelty that persists in its ori¬

ginai habitat and also spreads in neighboring ones,

any habitat tending to have two to five «neighbors»

much as for borders among States. Be as it may, in

Darwin’s favourite dictum by Milne Edwards his

bushy branchings refer to «variety» in which nature

is «prodigai», while Lamarck’s rare bifurcations

obviously refer to innovations in which nature is

«niggard».

As alluded in § 3 c), Darwin had laboured at great

length on thè phylogeny of barnacles, apparently

through much thè same principles as Lamarck’s.

Most likely due to this experience, in Origin (stand¬

ard, Ch. XIV) he hended up concluding that «analo-

gical or adaptive characters, although of thè utmost im-

portance to thè welfare of thè being, are almost value-

less to thè systematist » (analogical roughly corres-

ponds to parallel). Instead « very trifling characters »

would be thè best indicators of reai parentage if

enough of them had been available, as hardly thè

case at that time (cf. later on).

Darwin’s stand on systematics was soon reinforced

as it started being realized how often similar or near-

104

FRANCESCO M. SCUDO

ly identical animals had distinct origins, more often

than not through «parallel» changes. Newmayr’s first

precise documentation of such changes stimulated

Schiaparelli’s «topological» approach in terms of

switches among discrete, stable «fixed types» — i. e.

resulting in a tempo akin to «punctuated equilibria»

in contemporary jargon. Even if more effìcient than

standard character analysis, according to Schiaparelli

his topopogical approach to whole animai geometry

could not go very far in ascertaining thè reai parenta-

ges among animals. When his approach could actual-

ly be implemented, as was obviously far beyond thè

analytical machinery then available, Schiaparelli did

not believe it would allow to sort out thè relation-

ships among animai phyla (at variance from his

«mentor» Vignoli he believed they all had a common

multicellular ancestor, c.f. Scudo 1991).

Established schools of systematics somehow ma-

naged to downplay, or altogether ignore thè basic

problems so clearly stated by Lamarck, Darwin,

Newmayr, Schiaparelli, etc., as well as thè rather dif-

ferent ones symbiosis was posing (cf. below). These

problems kept re-surfacing, as for Hickling and

Wenz uncovering far more telling examples than

Newmayr’s of distinct origins of «identical» animals

— i. e. thè evolutionary series of Planorbis multiformis

in thè miocenic, lacustrine deposits of Stenhaim,

where three diverse modes of shell coiling can all

appear, in a definite order, in thè same individuai (cf.

e. g. Moret, 1940: 384). Shortly after, Piaget (cf. e. g.

1974) provided a deep behavioural and genotypical

analysis of analogous shell changes in a living coun-

terpart, Limnaea stagnalis.

Even ambitious theoretical analyses were often

carried on nearly independently of prior theories, or

of contemporary practice, or of both. Thus D’Arcy

Thompson rediscoveder from scratich a «topology»

nearly identical to Schiaparelli’s, though more expli-

citly relying on organismal mechanics and subsum-

ing continuity in evolutionary changes. An equally

eye-catching difference is that Schiaparelli kept stres-

sing his direct debt to Darwin, while D’Arcy Thomp¬

son kept elaborating on minor criticisms of Darwin

(cf. Scudo 1991, Bouligand, these proceedings). Near¬

ly simultaneously and independently of Schiaparelli,

Rosa (1899) had proposed a theory that was also

based on thè limited morpho-functional variability

within taxa, interpreting extinctions as mainly due to

a great reduction, or exhaustion of this variability in

thè course of evolution. Interestingly, Rosa reasoned

on morphogenetic processes and their changes in

terms of reactions of whole genomes (ideoplasms) to

conditions of life, fìrmly rejecting thè approach in

terms of ideoplasmic determinants and their strug-

gles as by Weismann & Co.. He thus preceeded by

decades Speeman’s empirical characterization of in-

duction as well as Schmalhausen’s theoretical rea-

soning to be mentioned later on. Subsequently Rosa

modified his theory in various ways, notably assum-

ing that branching is always dichotomic; through

Hennig this assumption eventually became very po-

pular among practicing systematists, on all kinds of

materials and with diverse meanings (cf. e. g. Baroni-

Urbani 1977).

Meanwhile palaeontology was ever more fìrmly

establishing a number of generalizations as empirical

laws, such that thè «pedunculum» of large taxa can-

not be preserved in thè record. In fact a major, very

succesful change would have a small diffusion and a

short persistance as such — most unlikely to appear

in thè fossil record — by soon giving rise to a major

radiation. According to another major «statistical»

law thè most ancestral forms of large taxa tend to

be «synthetic» and «polymorphic», in so far as thè

previous law allows to ascertain it (cf. e. g. Leonardi

1950). «Synthetic» means that thè earliest lineages

present diverse characters, each found alone, far

more developed among late descendants. «Poly¬

morphic» — i. e. «polytypic» in most posterior usa-

ges — means that in such early lineages individuate

tend to differ for thè presence or absence of one or

more characters.

Symbiosis continued being widely regarded as a

major mechanism in evolution mostly on thè basis

of generai theories such as Giglio-Tos’ (cf. § 1 c),

though a precise knowledge was stili largely confi-

ned to algal symbioses for animals and fungal ones

for plants. A major advance consisted in Pierantoni

and Sulk independently discovering, both in 1910,

that thè cells of previously enigmatic invertebrate

tissues (pseudovitellus) are densely packed with

fungal or bacterial symbiotes. The explosive in-

crease in factual knowledge following this discov-

ery made clear that all kinds of endocellular sym¬

bioses are common among protists while among

metazoans algal symbioses are mostly confìned to

their «lowest» representatives, fungal endocellular

symbioses do somewhat better higher uo in thè

«animai ladder» and bacterial ones stili higher, up

to colonial thaliaceans (where only taking place

through most anomalous modes of development,

cf. e. g. Pierantoni, 1940, Buchner 1965). According

to Pierantoni this distribution would strongly sup-

port thè symbiotic origins of eukaryotic organelles,

a stand categorically rejected by Buchner who sur-

vived Pierantoni and had a far wider audience. As a

result, thè symbiotic origins of organelles was

standard textbook knowledge in Italy around mid

century, but it took decades before it was seriously

considered again by thè biological community at

large (cf. Khakhina 1979 for analogous proposals by

Russsian botanists).

Around mid-century Schmalhausen (e. g. 1946)

was arriwing at conclusions parallel to thè paleonto-

logical ones above mostly from embryological and

biogeographical data, which he summarized into a

single law of evolution of morphogenetic reactions

(much as in Rosa’s sense, cf. above). Briefly told, any

novel reaction to conditions of life would originally

be somehow proportional to thè incidence and in-

tensity of some external stimulus. If sufficiently per-

sisting in a lineage, such a reaction would tend to

evolve into discrete morphs, as threshold responses

to external stimuli. Then each morph would tend to

become fixed in a distinct lineage, so that individuai

conditions of life would only determine whether or

not thè «normal» development of thè lineage can

take place. The development of this single norm will

then tend to become more and more «internalized»

— i. e. selectively modified to mature earlier in onto- 1

geny, regardless of conditions. The earlier in ontoge-

ny its development is completed, thè more a norm

can be diversely modified later in ontogeny, mainly

by thè active reactions of individuate to different ex¬

ternal conditions (i. e. it becomes «regulatory», cf.

SYMBIOSIS, THE ORIGINS OF MAJOR LIFE FORMS ANS SYSTEMATICS

105

also Scudo 1988, Wake, these proceedings). Taking

into account that a single morphogenetic reaction

often affects a number of characters, this law agrees

with thè palaeontological ones above as well as one

could hope. It also accounts for different modes of

interspecific associations being «statistically» related

to basic development modalities — e. g. thè «mosaic»

development of metazoans, which mostly results in

fixed norms of reaction, being more common in

forms with strict biocoenotic ties.

The same law can also be directly recasted to spe-

cifically account for thè evolution of symbioses. At

first thè individuals of a lineage either associate with

a given «guest» or they do not — possibly associating

with a somewhat different one — depending on con-

ditions. The «host» lineage then tends to break up

into one in which a given symbiosis becomes obli-

gatory and another in which it does not take place

— or another does — and this is often enough to

prevent their intercrossing. Further evolution often

results in thè host «internalizing» key functions of

thè symbiote, then discarded. This last process is

particularly evident, just by inspection, in several

examples of animai luminescence such as thè te-

leostean Apagon — i. e. thè light organs of some spe-

cies are powered by dense populations of bacteria

while closely related species have nearly identical

organs with endogenous light, and thè intensity of

its production is controllable at will. Being already

evident that viruses can carry genetic information

back and forth thè cytoplasm and thè nucleus (e. g.

Teissier 1952), such transfers were no longer pro-

blematic.

At mid-century preexisting theoretical and metho-

dological differences turned «virulent» through poli-

tico-ideological associations. Out of fierce battles a

«new synthesis» emerged as thè hardly contested

winner, imposing a strict order in which earlier no-

tions were rejected or «corrected» beyond recogni-

tion, while whole fìelds of investigation became

«prohibited». Thus thè tight forms of symbiosis em-

phasized in this review would not have been worthy

of serious consideration, apparently by requiring thè

steady operation of «group selection» to get establi-

shed (e. g. Williams 1966: 247), and by far too often

eventually resulting in «inheritance of acquired cha¬

racters». These are just two among a number of prior

errors, such as «beanbag genetics» or «typology»,

that were codified mainly by Mayr (e. g. 1982), and to

which I am unable to assign a precise meaning

(Scudo 1993b).

One can easily follow, however, how thè condem-

nations above went hand in hand with thè spread of

novel social usages, such as applying thè term sym¬

biosis mostly to bacterial and virai pathologies or

regarding much, or most DNA of thè higher metaka-

ryotes as «junk» — i. e. a hardly controllable parasite.

Synthetic theorists thus concentrated their attention

on thè severe conflicts that ought to arise between

endogenous nuclear components and allogenous, or

cytoplasmic ones, up to justify sex as a mechanism

reducing or eliminating such conflicts (e. g. Hurst

and Hamilton, 1992). To students of symbiosis in thè

old sense thè same data pointed, instead, to viruses

becoming thè «preferred» endosymbiotes, through

direct incorporation of their genomes, higher up thè

«animai ladder».

Another example of irreducible contrast between

«thè synthesis» and other theories comes from DNA

coding regions having incurred in far more gene sub-

stitutions than individuai selection could possibly ac¬

count for. This was called «non-Darwinian» evolu¬

tion and utilized to ascertain thè reai parentage

among organisms much as Darwin had prescibed,

mostly through a «neutral theory of molecular evolu¬

tion». This theory would justify most changes in cod¬

ing regions though random losses of alleles within fi¬

nite populations, at a rate per generation that would

almost solely depend on rates of mutation and thus

provide a near ideal «clock». This theory overlooks

that thè changes it predicts could only occur if all in¬

dividuals of locai populations were shuffled at ran¬

dom at each generation, and much thè same would

also occur in whole lineages (cf. e. g. Karlin, 1969: 155

in particular, Nagylaki 1992 and Scudo 1992c). In fact,

unless it were so, a genotypic variant could be lost by

a whole lineage only if lost at thè same time at all pla-

ces were it occurs, and this has a vanishing probabil-

ity. The «neutral theory» thus defies simple logics as

well as thè evidence that rates of synonimic base

changes tend to be much thè same, in long term ave-

rages, in organisms having as different generation

spans as, say, elephants and bacteria. Only in this

way synthetic theorists could avoid thè basic error

of «group selection» in darwinian theories starting

from Wallace, according to which most hereditary

changes would result from selection within popu¬

lations and among them, unless reflecting past ca-

tastrophic events that wiped out most of thè locai po¬

pulations of a lineage (e. g. Wright 1970, cf. also

Scudo 1990).

In thè light of thè scatter of points just made major

progress in systematics cannot be expected to mainly

spring from more direct empirical evidence, no mat-

ter how useful any such piece of evidence could

potentially be. Unless appropriately interpreted any

direct evidence is likely to be soon forgotten, as it

happened over and over again in thè past. Being far

from clear how to best utilize data of potential syste-

matic interest, all promising leads should be pursued

as far as possible. No matter how powerful on special

features or problems any one systematic procedure

now available could be, on its own it cannot go far in

sorting out thè reai parentage among living beings.

Major progresses in interpreting systematic data

should hopefully come from Schiaparelli-like proce-

dures, if nothing else since these have been among

thè least utilized so far (cf. Thom’s, Bouligand’s and

Presnov’s contributions). Also promising and hardly

exploited is thè fact that, early enough in develop¬

ment, changes in thè dynamics of a single celi po-

pulation can easily result in radicai macroscopic

changes (Giglio-Tos, 1900-1910, Voi. II in particular)

— e. g. between bilateral and radiate symmetry, mak-

ing one wonder about thè possible phyletic meaning

of «taxa» such as Radiata and Bilateria. To doubt thè

potential utility of topological methodologies in sys¬

tematics since it has not yet been proven is thè very

last thing one should do. Only since a few years, for

instance, Darwin’s originai guess on «trifling charac¬

ters» for human populations is firmly standing up to

evidence — i. e. their parentages as inferred by trifling

changes in gene frequencies remarkably agree,

among other things, with thè phylogenies of their

languages (Cavalli-Sforza et al. 1994).

106

FRANCESCO M. SCUDO

Appendix - Gender systems and evolution

Here I shall explore thè possible connections

between thè generalization on thè roles of gender

stated at thè opening of § 2 c) and thè truism that

thè metazoans and several metaphytes are characte-

rized by lacking a gametic or haplont segregational

gender System. Readers are assumed to be aware

of thè necessary botanical jargon and other techni-

calities.

«Loss» of thè haploid gender segregation com-

monly results in monoecism among thè otherwise

dioecious Bryophytes in some of which, such as

Bryum species, it is obtained by chromosomal du-

plication through apospory. The protandric gameto-

phytes thus resulting are always infertile at fìrst but

they become sexually fertile, as in nature, after sev¬

eral generations of vegetative reproduction (von

Wettstein and Straub 1942). In such cases thè change

from dioecism to monoecism must then be a semi-

automatic one, quite likely bringing together both

components of segregating, gender constitutive dif-

ferences in thè same chromosome complement.

These would be arranged so that either of thè two

sets of genes for gametic gender could be turned on

where and when appropriate, under thè control of

some «maternal» or «epigenetic» mechanism. Much

thè same kind of homogenization ought to also justi-

fy thè sexual conditions of lycopods, whose prothalli

can be strictly monoecious, or partially dioecious

under genotypic-environmental control, or strictly

dioecious in closely related species. On thè other

hand no trace of segregational mechanisms for

haploid gender is evident among ferns as thè ho-

mosporous ones are always monoecious, thè hete-

rosporous dioecious. Most likely, then, heterospory

originated in ferns by homogenizing thè haplont se¬

gregational mechanism after having reached a sporal

dimorphism substantial enough to «preserve» ha¬

ploid gender (heterangy, Thomson 1927, cf. again

Scudo 1973).

The relationship between amphimixis, genomic

sexual specializations and developmental complex-

ity are only part evident, displaying thè basic diffe-

rences between haplont and diplont gender systems

that Giglio-Tos had already recognized largely

through a priori reasoning (cf. Scudo 1994). Haplont

genomic dimorphisms always consist of constitutive

diallelic gender differences and, perhaps, also of

some reversible, epigenetic gender marking. When

such a dimorphism becomes «strong» enough thè se¬

gregational, haploid sex mechanism can be homoge-

nized, thus resulting in monoecism as in some bryo¬

phytes etc. (cf. above). A stili larger genomic gender

dimorphism quite likely forces analogous homogeni-

zations, such as those in thè higher metaphytes and

thè metazoans (cf. also § 3 b). Among them, indivi¬

duai, diplont gender differentiations seem always to

imply at least some degree of genomic, constitutive

gender differences and some form of reversible, epi¬

genetic gender marking proper, or other «clock» me¬

chanism (cf. above). Some individuai gender diffe-

rentiation is a priori expected to arise in originally

undifferentiated diploid systems as developmental

complexity increases, and this could only be achie-

ved by higher levels of genomic gender dimorphism

that, beyond some point, can hardly coexist in thè

same individuai whence diploid gender.

The tentative relationships between genomic gen¬

der dimorphism and developmental complexity in-

ferred above necessarily take somewhat different

forms according to whether development is an indi¬

viduai property, rather than a property of alternating

generations or of some cycle of generations. It is

evident, for instance, that amphimixis can be easily

lost to hermaphroditism, hybridogenesis, pseudoga-

my etc. if it is just one stage in population cycles of

developmentally stereotyped animals, such as wheel-

worms or aphids. This is hardly surprising since, in

appropriate conditions, thè repetition of a suffi-

ciently standardized, long established developmen¬

tal process could be achieved by sexual markings

other than epigenetic. On thè other hand it seems

that more complex or less stereotyped animals can

only loose amphimixis through exceptional chan-

ges such as interspeciflc hybridizations, or that am¬

phimixis cannot at all be lost in naturai conditions

by thè most complex matazoans and thè higher

metaphytes.

Acknowledgements — This paper owes many im-

provements to suggestions and criticism by Prof.s

Cesare Baroni-Urbani, Vaclav Paces, Marza D. Va-

sile, Gabriele Milanesi, Alessandro Minelli and by

my wife, Katherina. It was substantially enlarged to

satisfy thè request for more precise documentation,

or more elementary justifìcations, by some parteci-

pants to thè meeting. By courtesy of thè authors

recent references had been originally given while

stili unpublished.

POSTSCRIPT

Since this paper was written other works with ana¬

logous concerns were published, such as Margulis &

Cohen’s in Early life on earth (Columbia UP, New

York, 1994: 327-333). Many novel molecular data are

suggestive of special mechanisms in genomic inte¬

gration that are stili poorly understood — e. g. thè re¬

movai of 28 uridines and thè addition of 447 new

ones in thè ATPase subunit 6 precursor messenger of

Tripanosoma brucefs mitochondrion (Scott & Stuart,

Science: 286: 114-117, 1994). Nucleotide linguistics is

becoming a powerful tool to address all sorts of pro-

blems involving exogenous origins and genomic in¬

tegration, such as identifying as «imported» a num-

ber of open reading frames in Saccharomices cervi-

siae’s mithocondrion (Pietrowsky & Trifonov, Gene,

122: 129-137, 1992). On thè basis of many such novel

data multiple origins of mitochondria look ever

more likely. Also of great interest was to realize that

thè large intestinal symbiont Epulopiscium fishelsoni

and related forms have Gram positive features (Ang-

ert et al., Nature, 362: 239-241, 1993) and lack a pro-

perly eukaryotic nuclear organization (e. g. Ahern,

ASM news, 59: 519-521, 1993, their «nuclei» rather

rensemble Gram positive endospores). These oxi-

morons much strenghten thè view (cf. § 3 b) that pro¬

per nuclear structures had late, quite likely multiple

symbiotic origins. In this light bona fide chimaeras

apparently between two eukaryotes in terms of

rRNA sequences (e. g. Cryptomonas, Douglas et al.,

Nature, 350: 148-151, 1991) would be more easily

understandable if having in fact involved one a-nu-

cleated partner.

SYMBIOSIS, THE ORIGINS OF MAJOR LIFE FORMS ANS SYSTEMATICS

107

REFERENCES

Ager D., 1993 - The new catastrophism. Un. Press, Cambridge.

Alessandrello A., Arduini P., Pinna G. and Terruzzi G.,

1991 - New observations on thè Thylacocephala (Artropoda,

Crustacea). In: A. M. Simonetta & S. C. Morris, eds. The

early evolution of Metazoa and thè significance of proble-

matic taxa. Univ. Press, Cambridge: 245-252.

Arcangioli B., 1992 - A switch in time. Curr. Biol., 2: 323-325.

Bacci G., 1965 - Sex determination. Pergamon, Oxford.

Baccetti B., 1985 - Evolution of thè sperm celi. In: Biology of

fertilization. Acad. Press, New York, 2: 3-38.

Baroni-Urbani C. - Hologenesis, phylogenetic systematics and

evolution. Syst. Zool., 3: 343-346.

Basu A. R., Renne P. R., Das Gupta D. K., Teichmann F. &

Poreda R. J., 1993 - Early and late alkali igneous pulses and

high-3He piume origin for thè Deccan flood basalts. Science,

261: 902-906.

Becklemishev V. N., 1969 - Principles of comparative anatomy of

thè invertebrates. Univ. Press, Chicago.

Buchner P., 1965 - Endosymbiosis of animals with plant mi-

croorganisms. Interscience, New York.

Cairns-Smith A. G., 1985 - Seven clues on thè origin of life.

Univ. Press, Cambridge.

Canning E. U., 1988 - Nuclear division and chromosome cycle in

microsporidia. BioSyst., 21: 333-340.

Cavalier-Smith T., 1990 - Autogenous origin of Eukaryotes but

symbiotic origin of Metakaryotes. In: P. Nardon et ai, eds.:

571-574.

Cavalli-Sforza L. L., Menozzi P. & Piazza A., 1994 - The histo-

ry and geography of human genes. Un. Press, Princeton.

Cline T. W., 1993 - The Drosophila sex determination signal:

How do flies count two? Tech. Focus, 9: 385-390.

Cordón F., 1990 - Tratado Evolucionista de Biologia. Parte Se-

gunda. Aguilar, Madrid.

Darwin C. R., 1851 - A monograph of thè sub-class Cirripedia

(The Balanidae . . .). Roy. Soc., London.

Darwin F., 1887 - The life and letters of Charles Darwin. Murray,

London.

De Duve C., 1990 - The primitive phagocyte. In: P. Nardon et al.:

511-514.

De Duve C., 1991 - Blueprint for a Celi. Pattreson, Burlington.

Dones L., Tremaine S., 1993 - Why Does thè Earth spin For-

ward? Science, 259: 350-354.

Eigen M., 1987 - Stufen zum Leben. Piper, Miinchen.

Engelhardt H., Schuster S. C. & Bauerlein E., 1993 - An Ar-

chimedian spirai: thè basai disk of thè Wo lineila flagellar

motor. Science, 262: 1046-1048.

Folsome C. E., 1979 - The Origin of Life. W. H. Freeman & Co.,

San Francisco.

Giglio-Tos E., 1900-1910 - Les problemes de la Vie. Pubblished by

thè Author, Tourin.

Grassé P. P. & Noirot C., 1959 - L’évolution de la symbiose chez

les Isoptères. Experientia, 15: 365-408.

Green P., Lipman D., La Deana H., Waterson R., States D. &

Clavery J. M., 1993 - Ancient conserved regions in new

genes sequences and thè protein database. Science, 259:

1711-1716.

Haldane J. B. S., 1924 - A mathematical theory of naturai and

artificial selection. I., Proc. Camb. Phil. Soc., 23: 19-41.

Haldane J. B. S., 1957 - The cost of naturai selection. J. genet.,

55: 511-524.

Handlirsch A., 1908 - Die fossilen Insekten und die Phylogenie

der recenten Formen. Engelmann, Leipzig.

Harold F. M., 1986 - The vital force: A study of bioenergetics.

Freeman, New York.

Hong J.-L, Feng Q., Rotello V. & Rebek J. Jr., 1992 - Competi-

tion, cooperation and mutation: Improving a synthetic repli-

cator by light irradiation. Science, 255: 848-850.

Hurst L. D. & Hamilton W. D., 1992 - Cytoplasmatic fusion and

thè nature of thè sexes. Proc. R. Soc. London, 247: 189-194.

Jablonka E., 1994 - Inheritance systems and thè evolution of

new levels of individuality. J. Theor Biol., 170: 301-309.

Jablonka E., Lachmann M. & Lamb M. J., 1992 - Evidence, me-

chanisms and models for thè inheritance of acquired charac-

ters. J. Theor. Biol., 158: 254-268.

Khakina L. N., 1979 - Problema simbiogeneza: istorik-kritiches-

ky ocerk issledorani otchestrennykh botanikov. Acad. Nauk,

Leningrad. (Concepts of symbiogenesis - A historical and

criticai study of thè research of Russian Botanists, L. Margu-

lis & M. McMenAmin, eds., Yale Univ. Press, New Haven

1992).

Karlin S., 1969 - Equilibrium behavior of population genetics

models with non-random mating. Gordon & Breach, New

York.

Kasting J. F., 1993 - Earth’s early atmosphere. Science, 259:

920-926.

Leonardi P., 1950 - L’evoluzione dei viventi. Morcelliana,

Brescia.

Margulis L., Hinkle G. and Tzertzinis G., 1990 - Symbiosis

in thè origin of eukaryotic celi motility: Current status. In:

P. Nardon et al.: 523-526.

Mayr E., 1982 - The growth of biological thought, diversity, evo¬

lution and inheritance. Harward Univ. Press, Cambridge.

Milani A., 1988 - Long-term Behaviour of Planetary Orbits:

Theory and Numerical Experiments. In: Physics of thè Pla-

nets (S. K. Runcorn; ed.). J. Whiley & Sons, New York.

Miller S. L., 1993 - Prebiotic synthesis of organic compounds:

A review and new results. In: ISSOL ’93. School of Biology,

Barcelona: 36.

Moret L., 1940 - Manuel de paléontologie animale. Masson,

Paris.

Nagylaki T., 1992 - Introduction to theoretical population genet¬

ics. Springer, Berlin.

Nardon P., 1993 - Morphogenesis, differentiation and symbiosis.

Biol. Forum, 86: 327-328.

Nardon P., Gianinazzi-Pearson V., Grenier A. M., Margu¬

lis L. & Smith D. C., 1990 - Endocytobiology IV. INRA,

Paris.

Ohnishi K., 1990 - Celi machinery as a symbiotic complex of con-

temporary RNA organisms including tRNAS, rRNAS and

mRNAS: Evolution from RNA individuate to celi indivi¬

duate by cooperative symbiosis. In: P. Nardon et al.: 593-600.

Piaget J., 1974 - Adaptation vitale et psycologie de l’intelligence:

sélection organique et phénocopie. Hermann, Paris.

Pierantoni U., 1923 - Gli animali luminosi. Sonzogno, Milan.

Pierantoni U., 1940 - Nozioni di biologia. UTET, Tourin.

Rizzo P. J., 1991 - The enigma of thè dinoflagellate chromosome.

J. Protozool., 38: 246-252.

Rosa D., 1899 - La riduzione progressiva della variabilità e i suoi

rapporti coll’estinzione e coll’origine delle specie. Clausen,

Tourin.

Rosati G., Lenzi P. & Verni F., 1993 - «Epixenosomes»: Peculiar

epibionts of thè protozoan cibate Euplotidium etoi: Do their

cytoplasmic tubules consist of tubolin? Micron, 24: 465-471.

Ruby E. G. & McFall-Ngai M. J., 1992 - A squid that glows in

thè night: Development of an animal-bacterial mutualism.

J. Baci, 174: 4865-4870.

Schmalhausen I. I., 1946 - Faktorii evolutsii; teoria stabilizi-

rushego otbora. Akad. Nauk, Movska (Factors of evolution:

The theory of stabilizing selection, ateo in abridged English

edition, Blackiston, Philadelphia, 1949).

Schmalhausen I. I., 1968 - The origin of terrestrial vertebrates.

Acad. Press, New York.

Scudo F. M., 1967a - The adaptive value of sexual dimorphism:

I. Anisogamy. Evolution, 23: 36-49.

Scudo F. M., 1967b - Selection on both haplo and diplophase.

Genetics, 56: 693-704.

Scudo F. M., 1973 - The Evolution of sexual Dimorphism in

Plants and Animate. Boll. Zool., 40: 1-28.

Scudo F. M., 1988 - «Ethology», «ecology» and «philosophy».

236-250. In: (B. Goodwin et al., eds.) Dynamic structures in

biology. Univ. Press, Edinburgh.

Scudo F. M., 1990 - Darwinian theories and animai taxonomy.

Boll. Zool, 57: 181-206.

Scudo F. M., 1991 - Morphology and systematics before and after

Schiaparelli. Riv. Biol.: 130-134.

Scudo F. M., 1992a - F. Cordón - Tratado de biologia evolucio¬

nista - Historia naturai de la acciòn y experiencia (book

review). Boll. Zool., 59: 533-535.

Scudo F. M., 1992b - The early evolution of Metazoa and thè sig¬

nificance of problematic taxa (A. Simonetta & S. Conway,

eds., book review). Boll. Zool, 59: 531-533.

Scudo F. M., 1992c - A Darwinian theory of molecular evolution.

In: V. A. Ratner e N. A. Kolchanov (eds.). Modelling and

computer methods in molecular biology and genetics. Nova

Sci., New York: 369-378.

Scudo F. M., 1993a - La «Ortogenesi» e le estinzioni di massa.

Paleocronache, I: 48-58.

Scudo F. M., 1993b - E. Mayr - La «sintesi moderna» e la «storia

del pensiero biologico» (book review). Paleocronache, I:

88-94.

108

FRANCESCO M. SCUDO

Scudo F. M., 1994 - Ermanno Giglio-Tos: History and myth in

thè origins of major life-forms. Biol. Forum, 87: 330-338.

Scudo F. M. & Ziegler J. R. (eds.), 1978 - The golden age in

theoretical ecology: 1923-1940. Springer, Berlin.

Scudo F. M., Sacchi L., Freudenberg M. A., Grigolo A. &

Galanos C. MS - Membrane characterization of cockroa-

ches’ endocellular symbionts. submitted to Endocit. & Celi

Res.

Sharpton V. L., Burke K., Camargo-Zanoguera A., Hall S. A.,

Lee D. S., Marìn L. E., Suàrez-Reynoso G., Quezada-Mu-

neton J. M., Spudis P. D. & Urrutia-Fucugauchi J., 1993 -

Chixulub multiring impact basin: Size and other characte-

ristics derived from gravity analysis. Science, 261: 1564-1567.

Smith D. C. & Douglas A. E., 1987 - The biology of symbiosis.

Arnold, London.

Strauss E. G., Strauss J. H. & Levine A. J., 1990 - Virus evolu-

tion. In: (D. M. kempe ed al., eds.) Virology. Raven, New

York: 167-188.

Symons R. H., 1992 - Small catalytic RNAs. Ann. Rev. Biochem.,

61: 641-670.

Teissier G., 1952 - Dynamique des populations et taxinomie.

Ann. Soc. Roy. Zool. Belg., 83: 23-44.

Thomson B., 1927 - Evolution of thè seed habit in plants. Trans.

Roy. Soc. Can., 5: 229-272.

Vachon M., Russeau G. & Laissus Y. (eds.), 1972 - Inédits de

Lamarck. Masson, Paris.

Van De Peer Y., Neefs J. M., De Rijk P., De Vos P. and

De Vachter R., MS - About thè order of divergence of thè

major bacterial taxa during evolution.

Von Wettstein F. & Straub J., 1942 - Experimentelle Untersu-

chungen zum Artbildungsproblem. Ili: eitere Beobachtun-

gen an polyploiden Bryum-sippen. Verebungs., 80: 272-279.

Walker R. A. & Shetz M. P., 1993 - Cytoplasmic microtubule —

associated motors.

Weismann A., 1904 - The evolution theory. Arnold, London.

Williams G. C., 1972 - Adaptation and naturai selection. Univ.

Press, Princeton.

Wright S., 1970 - Random drift and thè shifting balance theory

of evolution. In: (K. Kojima, ed.). Mathematical topics in po-

pulation genetics. Springer, Heidelberg: 1-31.

-

Francesco M. Scudo: Istituto di Genetica Biochimica ed Evoluzionistica (CNR), Via Abbiategrasso 207, 1 27100 Pavia ITALIA

Systematic Biology as an Historical Science

Memorie della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano

Volume XXVII - Fascicolo I - 1996

Alberto M. Simonetta

Systematics: is an historical perspective useful to understand

modem debates on systematics

and are we really equipped for sound evolutionary systematics?

Abstract — Consideration of thè very early history of concepts in biology and of their influence on formai taxonomy

shows that some basic current concepts are stili rooted in extremely ancient ideas. Awareness, for instance, of thè neopla-

tonic roots of modern trends in systematics, may be useful in thè current debates.

That thè last twenty or thirty years of debate over

systematics have helped to revive interest in practical

and theoretical systematics is obvious and this has,

by itself, been beneficiai. However I am worried that,

unless thè current arguments among thè various

schools are really clarified, we may run into as devas-

tating a situation as it was with thè neglect of syste¬

matics which plagued biology both prior to and im-

mediately after World War II.

Anyone who has happened to read my papers on

generai problems of systematics knows that cladism,

be it Hennigian or transformed, has been my special

target over thè last few years (Simonetta 1983, 1988,

1990, 1992, 1993). However I am not happy with any

of thè main schools of systematics. Indeed blind ac-

ceptance of this or that model of systematics by too

many zoologists is swamping libraries with contribu-

tions which, should thè particular creed of their

authors be finally discredited, will fall to pieces, leav-

ing heaps of sherds extremely difficult to handle and

which will also not be easily disposable.

Here, both to avoid repetition of arguments which

have not yet been challenged by disagreement, I

shall suggest that there are other stili poorly explored

aspects in thè systematic debate. I shall therefore

outline some historical considerations, as I have a

sort of feeling that thè history of systematics, though

it forms a minor chapter in any history of biology,

had a subtle and underground role in shaping thè

groundwork of systematics which has been singular-

ly overlooked.

In spite of repeated claims that systematics was

born with Aristotle and that thè arguments of anc¬

ient authors on thè scala naturae are arguments

about systematics, I think that, upon consideration,

both claims misconstruct what Aristotle, Albertus

and others had in mind. Although they did, indeed,

provide some ready materials and ideas for true sys-

tematists, when finally evolved, they were really

concerned with what we would cali «comparative

zoology» in a very broad sense.

Aristoteles’ so-called classifìcations have to be pie-

ced together frorn thè Stagyrite’s arguments, simply

because probably he never thought to formalize then

in a «System».

Aristotle was indeed thè first and for over a thou-

sand years, thè greatest of zoologists, but he dealt

with an extremely limited range of animals, and he

could describe thè structure, biology and some com¬

parative morphology of some 500 kinds of animals

without any need for a taxinomy. The very fact that

in his writings thè Stagyrite completely ignores a

large number of animals which were both common

and conspicuous in he regions where he lived for

years, shows that he actually picked up for discus-

sion those animals which, for whatever reasons, he

deemed useful in order to elucidate some problems

that he considered as being particularly signifìcant.

In some sense, just as thè Organon was considered by

Aristotle as an instrument for ascertaining thè logicai

truth of statements, so his zoological books are

aimed to point out signifìcant problems of biology

and illustrate by which methods and principles they

could be clarified.

The wealth of zoological information built up very

slowly until thè end of thè XV century, slower, in¬

deed than that on plants, and for good reason. Her-

bals were first to be generally illustrated: illuminated

herbals of Byzantine and Longobard times are stili

extant (thè Dioscorides Longobardorum, copied in

N Italy in thè Vili century, thè Byzantine codices of

Naples, of thè early VII century, and of Vienna,

dated c. 512 A.D. and based for thè figures on thè il-

lustrations by Cràteva, who was active in thè early

I century b.C.) and it is clear that they follow a pat¬

tern established early in thè Roman imperiai times.

Indeed thè problem of how to organize information

became obvious to herbalists first, because physi-

cians and apothecaries needed to identify plants cor-

rectly, if they were to avoid thè risk of pisoning,

instead of healing, their customers. Thus, since

Theophrastus, plants were very often grouped, even

if such groups were based on rather inconsistent cri-

teria. For example in thè catalogue of a (planned?)

botanical garden in Mantova, thè duke’s physician

G. F. Palperia, a contemporary of Aldrovandi, in

1625 had groups such as «Plantae leguminaceae et tri-

foleae, Plantae tuberosae et carnoseae radicum, Plan¬

tae catarticae vel solutivaeb> (Franchini & al., 1979).

In thè meantime Lullus (c. 1235-1315) and his fol-

lowers built generai theories of nature and knowled-

ge on Scotist lines (cpr. Yates, 1982). They argued

that during creation all thè various qualities and

powers of God imposed their effects on undifferen-

110

ALBERTO M. SIMONETTA

Srboi ekméfttalte» BrbciM&ttaUo.

Fig. 1 - Examples of Lullist trees from a late XIV century codex, note thè roots nourishing thè tree and thè leaves and fruits

representing thè world’s realities.

tiated matter in various balances and combinations,

basically through a doublé mechanism. First divine

qualities impinged on thè process of creation, and in

Lullist Trees (Fig. 1) this is likened to thè roots of thè

tree, by which it receives nourishment; second, by

being variously redistributed by a hierarchy of pro-

gressively subordinated entities, be they angels, ce-

lestial bodies etc., thè actual individuai objects, thè

leaves, were at last created. And just as leaves are

continuously shed and renovated, so it is with thè

turnover of creatures. As God was supreme reason,

so creation must be, above anything else, logicai, and

by an appropriate logicai instrument (in Lullism

«combinatorial» logie) it can be penetrated.

At thè same time thè trees of creation, which

could be imagined for all sorts of things, from ani-

mais to medicai produets and even intellectual enti¬

ties, had to be reconstructed in their logicai develop-

ment and, as plainly stated by Dante «Ché non fa

scienza senza lo ritenere avere inteso», this under-

standing had to be memorized in order to be maste-

red. Here thè Ars memoriae carne on its own and

Lullus himself was one of thè great masters of it

(cf. Yates, 1982, Rossi, 1983).

If one considers that, probably under thè influence

of Arab scholars, Aristotelean categories were con-

sidered as being reai material operators in thè fram-

ing of thè world and so were such divine qualities as

Bonitas, Misericordia , Justitia etc., one perceives that

thè debate between Realists and Nominalists, during

thè late medieval times was much more complex

than it is usually described in texbooks.

At thè eve of thè XVth century thè true aristote-

lians had moved well away from orthodox aristote-

lism into a nominalistic epistemology (properly

named «terminism»), while naive realism had deve-

loped into Hermetic-neoplatonism and Lullian trees

were familiar as expressing not genealogical kinship,

but thè equally true generation kinship.

Then thè age of explorations and discoveries

swamped thè scholars with innumerable new kinds

of animals and plants, and they were faced with thè

Herculean task of organizing this new knowledge. At

thè same time thè rarity, oddness or sheer beauty of thè

manifold produets of nature stimulated thè naturai ten-

dency of men to collecting, and museums were bom.

I have just said that at that time scholars were pro-

vided with two alternative intellectual tools for their

task: traditional Aristotelism turned nominalistic by

thè medieval university scholars, or Neoplatonism-

Hermeticism-Paracelsism, rooted in Lullism, with a

strong realistic tinge and commonly credited with an

Augustinian parentale, which made it, if not ortho¬

dox, at least defensible on religious grounds.

People like Aldrovandi and especially Cesalpino

tried to use thè first tool; others, for instance thè

groups linked with thè Academia dei Lincei or thè

Royal Society (like Ray), thè second one.

There is indeed a subtle difference between thè

ideal Museum of Aldrovandi (now preserved, to-

SYSTEMATICS: IS AN HISTORICAL PERSPECTIVE

USEFUL TO UNDERSTAND MODERN DEBATES

111

gether with all thè accompanying notes, by thè Uni¬

versity of Bologna), which he conceives as a sort of

material Encyclopedia, thè precise counterpart of a

set of files (and indeed he did file all thè specimens

of his own museum in thè most complete and exaus-

tive way, with all sorts of cross references etc.), a

source of retrievable information, thè more generai

and complete thè best, and thè Museum seen in thè

light of Lull’s «Ars». This second kind of museum is

a material itinerary symmetrical with thè «World’s

theatres», a sort of treatise built on specimens, in

which thè relevant ideas are linked into an organic,

chained argument, which will lead both to remembr-

ance and to knowledge (cpr. Rossi, 1983).

Both kinds of musea are stili with us: thè lullian

one in thè public exibits, which teli one story, and

Aldrovandi’s in thè study collections, where alterna¬

tive stories are developed.

Books, being musea in words, had to follow or,

perhaps, to be thè blueprint for thè material musea

being assembled.

It should also be noted, as it is customary to assu¬

me that thè «Baconian» scientifìc attitude supersed-

ed thè medieval one and that modern Science has

broken with both thè platonic and thè aristotelic tra-

dition, that Sir Francis Bacon himself largely depart-

ed from his own principles when writing of Naturai

History: His Par ascese ad historiam natura lem et ex-

perimentalem and other writings clearly expound

principles which are directly linked with those of thè

Ars memoriae» (cpr. Rossi, 1957).

John Ray, whose great influence in framing thè

principles of systematics has always been aknowled-

ged and who was especially influential on Linnaeus,

is known to have developed his basic systematic

principles while, collaborating with Willoughby and

Bishop Wilkins for thè development of thè «univer¬

sa! language», Ray actually developed a special clas-

sifìcation for Wilkins that was actually conceived as

an integrai part of thè project and was strictly based

on logicai division, though he was quite unhappy

with it as he thought thè framework too rigid and of

limited scope (cpr. Rossi, 1983, Mayr, 1982).

Thus, it seems conceivable that, more or less con-

sciously, thè joint requirements of a realistic-neopla-

tonic frame of mind, which was prevalent in North¬

ern Europe, and thè requirements of cataloguing

specimens did naturally lead to thè kind of classifica-

tion which we cali Linnean.

Linnaeus was an exemplarly practical mind and

did not generally delve into purely theoretical spe-

culations (when he did he occasionally made

thè grossest mistakes, such as when he denied thè

existance of spermatozoa as living beings). Linnaeus

generally formulated his theoretical ideas in thè

form of brief statements and rather set himself to

improve and generalize on paths tentatively trodden

by others.

However there is no doubt, as it is amply borne by

his repeated hymns to thè Divinity, that he regards,

true to thè neoplatonic tradition, that thè correct and

«naturai» listing and describing of being led to true

knownedge of God Himself in his works, which is a

classical attitude in Medieval theology of truth. Mo-

reover, when we examine thè various stages of thè

development of his classifìcation of plants and his

discussion of thè theoretical principles on which he

built his work, there is no question of thè influence

that thè combinatomi mnemotechnics and thè lul-

list tradition had on him: in fact he first derived his

26 basic characters which, also because of their num-

ber, he called Litterae vegetabi/ium, then by combina¬

toria! methods he joined them into «words», which

characterized his taxinomic order, and he had no

doubt that thè «empty» words would eventually be

filled by new discoveries, which is pure Leibniz.

To discuss thè various traditions, besides thè neo¬

platonic (such as thè Augustinian-Lutheran), which

may have been at work in shaping Linnean systemat¬

ics would need a book, rather than a paper, and thus

I leave this point, simply recalling that Linnaeus’

father and grandfather were Lutheran preachers.

For thè whole of thè XVIII century and thè first

half of thè next biologists had to choose between two

alternatives: either they subscribed to thè thesis, ho-

noured by all Christian creeds, that thè naturai

world, being thè work of God, portrayed thè same or-

derly Supreme Mind and was built of logically and

indeed necessarily related objects, shadowing a Lul¬

lian tree; or else they took a defìnitely atheistic view,

as D’Holbach and several French did, but to thè

same practical result.

Indeed, by thè XVIII century classical scholasti-

cism had become entirely discredited in protestant

areas and among «Libertines» everywhere. But also

in thè Catholic media, where, because of thè author-

ity of St. Thomas Aquinas, thè bulk of scolastic phy-

losophy was stili generally studied, it was customary,

out of thè classroom, to decry it. So, down with scho-

lasticism went nominalism.

Anyway, ever since Aristoteles had used thè word

«genos» to band related items or concepts (and he

was justified by Greco-Roman tradition, where thè

«Gens» was supposed to share thè same «Genius»

even when relationship was rather by religious tradi-

tional links than by reai blood kinship), thè term,

which could have been translated indifferently either

as «genus» or as «Family», was familiar in Science

and philosophy with this ambiguous association

both to kinship by thè mechanisms of creation and

by reai reproductive continuity.

Thus thè framework for evolutionary ideas was

prepared: Once generati o aequivoca had been gene-

rally discredited, living beings were naturally con-

sidered as being related, at least kind by kind, by ge¬

nealogica! relations which, just as human family

trees, could be expressed by dedrograms, and thè

«little» step of limited evolution, such as advocated

by Buffon and by Linnaeus himself in his later years,

was self-suggested by thè usage of words such as

family and Genus, with their strong genealogical

implications.

Indeed it seems that during thè XVII and XVIII

centuries and well into thè XIX century, thè majority

of thè best generai zoologists and botanists were

rather subconsciously dependent on Platonism (ac¬

tually Goethe was a spinozist in philosophy, but ra¬

ther a platonist in Sciences and such Naturphiloso-

phen as Schelling or Ocken were openly platonists),

while thè great comparative anatomists and pysiolo-

gists, such as G. Cuvier, were more «aristotelically»

minded, with Darwin nicely in thè middle, pragmati-

cally taking thè best of both.

Darwinian theory, turning biology to a large extent

into a historical Science, should have reopened thè

issues, as Aristoteles himself had noticed that histo-

112

ALBERTO M. SIMONETTA

rical statements could not be verifìed by classical log-

ics, and thè difficulty had been further exaustively

analyzed by medieval scholars, who had shown that

any proposition where time was involved can not be

proven by dichotomous logics.

However, Darwin himself and most of his follow-

ers, including those who plunged into an all out at-

tack on traditional religions, generally avoided thè

more theoretical implications of their stand and may

even have been unconscious of pressing into their

Services time honoured devices, which had been ori-

ginated for quite different purposes, as one may see,

for instance by comparing thè «trees» of thè pious

Lullus (Fig. 1) with those of thè atheist Haeckel

(Fig. 2): they were too busy establishing thè fact of

evolution and its mechanisms, to worry about its im¬

plications for systematics. More specially, though at

least Darwin himself was aware of it, they should

have given more attention to thè impossibility to re¬

concile thè endeavour to reconstruct a historical nar¬

rative of which thè individuai specimens known were

episodes (just as artifact or documents are in human

history), with a belief of thè reality of taxa, which was

rooted on entirely different principles; and that while

«Linnean» taxinomy, as it was practically thè best

possible in order to manage thè evidence, had to be

preserved and used.

As I have argued other aspects of thè debate on

systematics elsewhere, I shall not repeat here my ar-

guments in favour of regarding formai taxinomy as a

necessary, albeit, conventional tool for all biological

researches (Simonetta 1992, 1993), rather I have been

aiming here to show that, as we are human beings,

we are, Willy nilly, thè products of cultural evolution,

is it possible that in thè minds of each one of us thè

ghosts — thè old archetypes — are stili living and

moulding our approach to systematics?

For instance, I feel that there is a case for arguing

that thè practice of certain algorithms in cladistic,

and especially transformed cladistic systematics is

«phylogenetically» related with some Hermetic-

cabbalistic renaissance practices, through Oken (with

his dichotomus differentiation, advocated in his

« Lehrbuch der Naturphilosophie in 1809 and his

slightly previous, proclaimed «neopythagoric»

phase), Gothe, Franz Baader and others.

Consideration of thè medieval «terministic» de¬

bate recently led me to consider thè study of thè

messages relayed by thè scientific literature and

whether its semiotics should not be propedeutic to

consideration of thè philosophy of biology. Though I

have not gone far enough to have any definite ideas,

I have a strong feeling that consideration of what

really happens in thè sequence: «observation of evi-

Zonoplacenfalia —«Deciduala

(.'anuria

Dis coplacentalia

Simiae s. Pithrri

Fig. 2 - Two of thè many «trees» proposed by Haeckel, leaves and

fruits are substituted by names, but thè similarities with Lull’s

imageing is obvious.

SYSTEMATICS: IS AN HISTORICAL PERSPECTIVE USEFUL TO UNDERSTAND MODERN DEBATES

113

dence— organisation and interpretation of it-> trans¬

fer into verbal information-» interpretation of verbal

information», may really contribute to our debates.

Indeed, when we consider this sequence, it is clear

that we have here a process of progressive abstrac-

tion and that thè result is only related to thè phe-

nomenon, but that thè relation is an indirect one.

It appears that modern semiotics (cf. Eco, 1990) lar-

gely revive thè positions of medieval terminists

maintaining that concepts and more generally all

collective terms «stand for» something, are suppositi

for something reai, but that they imply a «pre-

sumption» about them, which implies a complex

attitude to knowledge: strictly objective knowledge

being absolutely denied, while a probabilistic, if

necessarily biased, knowledge being both possible

and valuable.

Subjective bias in presumed objective methods

may more or less always be proved. For instance it is

easy to show that all kinds of cladistic analysis are

based on strictly typological assumptions, which are

and work independently from thè proclaimed evolu-

tionary and systematic principles of thè same authors

who perform them.

It is a well known fact that, while any writer, in-

cluding thè scientist, puts himself into his work, his

work while being written, impinges on thè writer

subconscious and shapes it, just like any other writ-

ing he has happened to read since his childhood.

Therefore it is not surprising that, in biology, such a

long tradition of «realism» urges so many excellent

scholars to strive for a «System» good for all seasons,

for thè «good» species concepts, for «rules» which

will work out thè relationships of living beings with

regular reliability.

There is an almost generai consensus that thè

«System» must mirror, as far as possible thè best evo-

lutionary reconstructions. However thè reai scope

and thè essential autonomy of phylogenetic studies

with respect to systematics must be fully understood.

Hennig (1966), as usually wrongly, maintains that

phylogenetic connections are among species or

among taxa of supraspecific level; obviously it is per-

fectly legitimate to study thè relationships of abstract

concepts, such as classes, but this is essentially dif-

ferent from studying phylogeny (See Simonetta 1992,

1993). Indeed phylogenetic studies are concerned

with thè possible relationships of known specimens,

which are assumed to mirror thè relationships of thè

populations past and present to which these indivi¬

duate belong; formai systematics, instead, is a mes-

sage with a complex function.

If we fail to make here a clear distinction between

thè reconstruction of phylogenetic connections and

formai systematics, instead of having a «one way»

lane from evidence to interpretation, and from inter¬

pretation to filing and retrieving both thè informa¬

tion and thè interpretation and stop there, we shall

always be in danger of a feed-back: assumed syste¬

matics impinging on interpretation of data or, worse, a

systematic arrangement built on some presumed rules

prompting a stereotyped way of reading thè evidence.

Should not we instead be afraid of all kinds of or-

thodoxies and endeavour to fight them?

Having thus tried to give a bit of attention to what

may, perhaps, be deemed a marginai aspect of thè

debate, but one that I feel to be signifìcant in thè

study of such an elusive problem as that of thè signi-

ficance of taxa, a big query follows.

Have we got a really good theory of evolution, im-

proving consistently on Darwin’s? I am afraid that we

have not.

Granted thè basic Darwinian principle of variation

and selection, both stabilizing and directional, on

one side none of thè current generai accounts of thè

theoretical aspects of evolution, does take into full

account all known facts of genetics, nor do they ac-

count for all thè different ways selection has been

shown to operate both as individuai and as group se¬

lection. We have no really satisfactory generai expli-

cations for thè coordinate evolution of complex mor-

phological, physiological or ethological patterns, nor

for thè apparent fact that some kinds of mutations or

some types of selection are prevalent among certain

organisms, while alternative ones are commoner in

other, sometimes related, groups. Finally we have

several elegant and attractive models of evolutionary

events, especially in morphology, where they stem

from Schiaparelli’s and D’Arcy Thompson’s pioneer

work, but we do not really know how to correlate

them with known facts of genetics and of naturai

selection.

If we, as I expect, agree that systematics should

mirror, as far as this is practically possible, thè course

of evolution a «new synthesis» is needed against

which theories and practices of systematics must be

tested, and I expect, found wanting.

In thè meantime, I am afraid, we have to go on by

old principle that a good taxon is that which is main-

tained by a good systematist.

REFERENCES

Eco U., 1990 - I limiti dell’interpretazione. Bompiani, Milano,

369 pp.

Rossi P., 1988 - Clavis Universali. Arti della memoria e logica com¬

binatoria da Lullo a Leibniz. II ed. Il Mulino, Bologna: 340 pp.

Rossi P., 1957 - Francesco Bacone. Dalla magia alla scienza.

Laterza, Bari: 528 pp.

Simonetta A. M., 1983 - The myth of objective taxonomy and

cladism: mach ado about nothing. Atti Soc. tose. Sci. nat.,

Mem. Ser. B, 89: 175-186.

Simonetta A. M., 1988 - Logica, tassonomia e realtà. In: G. Ghiara

(ed.). Il problema biologico della specie. Collana U.Z.I. Proble¬

mi di Biologia e Storia della Natura. Mucchi, Modena, 1: 59-78.

Simonetta A. M., 1990 - On thè significance of ecotones in

evolution and on thè significance of morphologic differen-

ces in primitive taxa: reflexions and hypotheses. Boll. Zool.,

57: 325-330.

Simonetta A. M., 1992 - Problems of systematics: Part 1. A criti¬

cai evaluation of thè «species problem» and its significance

in evolutionary biology. Boll. Zool., 59: 447-464.

Simonetta A. M., 1993 - Problems of systematics: Part. 2. Theo¬

ries and practice in phylogenetic studies and in systematics.

Boll. Zool., 60: 323-334.

Yates F. A., 1982 - Lull and Bruno, collected essays. Routledge &

Kegan, London.

114

ALBERTO M. SIMONETTA

Alberto M. Simonetta: Dipartimento di Biologia Animale e Genetica «L. Pardi» - Università di Firenze,

Via Romana 17, 1-50125 Firenze ITALIA

Systematic Biology as an Historical Science

Memorie della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano

Volume XXVII - Fascicolo I - 1996

René Thom

Qualitative and quantitative in Evolutionary Theory

with some thoughts on Aristotelian Biology

Abstract — This paper aims to show thè relation between qualitative and quantitative considerations (in Biology and

elsewhere). It is argued that quality cannot be reduced to quantity, as is so often held with conviction. W e propose appli¬

cation of qualitative thinking for thè Darwinian problem of speciation and discuss Lyell’s «uniformitarianism» applied

to Darwinism. The discrete qualitative character of cellular morphogenesis necessarily entails qualitative discontinuities,

however small these may be quantitatively.

It is now commonly held that any qualitative diffe-

rence may be expressed quantitatively. The old say-

ing of thè British physicist Rutherford (around 1900),

«Qualitative is nothing but poor quantitative», is a

statement that most of today’s scientists are quite

willing to endorse. For obvious reasons, thè compu¬

ter Science industry of this last half-century has done

quite a lot to impose thè idea on thè public mind. But

it may now be time to react against this widespread

belief.

One may wonder why a former mathematician

should fmd it necessary to defend thè essential speci-

ficity of quality, a concept somewhat alien to thè

world of numbers. In thè same way, one may wonder

why biologists have been so eager to tread thè path

of quantization. Think, for instance, of thè impact

of thè statistical school of thè early 1900’s (Fischer,

S. Wright, after Galton...) which led to thè triumph-

ant revival of Darwinism under thè name of neo-

Darwinism. Classical biologists used, around 1800

when their Science was new, thè concept of animai

organization. The Latins knew thè locutions Situs

Partium, thè Greeks sustèma tón morión. Now people

believe that it’s all in thè DNA and that life is more

interesting at thè molecular level — inside thè celi —

than at thè gross level of «big animals». Yet I hope

that among my hearers a sufficient number will

agree that thè study of «large animals» is stili a rather

significant part of Biology.

Now, is animai organization a qualitative or a

quantitative concept? The answer is not so easy.

For quality frequently creeps into mathematics

under thè guise of number. Is thè quantitative ine-

quality a < b (a less than b) a quantitative or a quali¬

tative relation? Consider thè integers 1 and 2. Most

people would immediately say that thè relation 2 > 1

is a quantitative one, as 2 = 1 + 1. But thè couple of

integers in thè order (1, 2) is not thè same as thè dyad

in reverse order (2,1): here enters thè piane, thè con-

tinuous 2-dimensional Euclidean space (endowed

with horizontal and vertical gradients) needed to

write down thè formula. Because of this spatial em-

bedding, thè two dyads (1,2) and (2,1) have to be

considered as qualitatively different. Our grammars

justify this viewpoint by distinguishing thè Cardinal

number (of nounlike function) from thè ordinai

number (an adjective). There is little doubt that thè

consideration of an organ’s relative position with res-

pect to others’, fundamental in defming homology

between similar bones or organs in different species

(remember Owen’s definition as quoted in Professor

Minelli’s paper), refers to this concept; and this also

requires that a System of three «gradients» (or space

coordinates) be specified. Another apparent inter-

mingling of number and quality occurs in topology.

Consider thè topologica! classification of closed

oriented surfaces. Such a surface can always be con-

structed by adding k handles to thè standard two-di-

mensional sphere S2. This positive integer k is called

thè genus of thè surface (thè cases k = 0, 1, 2 are reali-

zed respectively by thè two-sphere S2, thè two-di-

mensional torus T2, and thè Bretzelflàche). Here thè

differences, although expressed by a varying integer

q, thè genus, are fundamentally of a topological, qua¬

litative nature. Hence thè answer: Many apparently

quantitative relations are in fact of a qualitative na¬

ture, inasmuch as they involve topological relations

more specific than those of thè quantitative ones.

After all, between situs partium and analysis situs,

thè name given by Leibniz to topology, there is an

obvious affinity. When discussing a numerical equa-

lity a = b with regard to two entities A and B, one has

to distinguish thè case where a and b relate to ob-

servable characteristics of distinct entities A and B

from thè case where A and B are shown to be identi-

cal through this equality of measurement. For exam-

ple, two quantities of thè same matter and of thè

same weight are interchangeable. It is clear that if we

consider two evaluations of identical quality in two

different entities A and B, that does not imply thè

identity of thè two «substances», in philosophical

terms. Since a = b is thè most typical form of rela¬

tion, it would be useful to analyse thè medieval dis-

tinction between substance and predicate. To do this

we place ourselves in thè framework of Aristotelian

metaphysics, which has brought to thè study of this

problem some intuition that is stili highly relevant.

The relation of Genus to Species

The couple Genus-Species, which has not yet di-

sappeared from our taxonomies, owes its definition

to Aristotle. Needless to say, this defmition is infini-

116

RENÉ THOM

tely broader than thè usuai biological use of thè

terms. In Aristotle thè notion has a logicai origin.

Two qualities (a) and (b) are said to belong to thè

same genus (Tevoo in Greek), if, whatever thè entity

X, thè two propositions: X is a and X is b cannot be

simultaneously true. In other words (a) and (b) are

contrary (a wider notion than contradictory, where

thè genus is in one dimension). This means that, in a

metaphorical sense, qualities (a) and (b) compete

with each other to occupy a space (G), which must be

considered as a piece of matter in thè sense of Aris-

totle’s hylè, that is to say a continuum ( sunechès ) si¬

mular in principle to thè Euclidean one. In particular,

one can by mental experiment continuously deform

concept (a) into concept (b) (and vice versa) without

ever, throughout this deformation, having thè im-

pression of any brutal discontinuity in thè nature of

thè affect.

On thè contrary an affect such as (a), endowed

with a certain psychic individuality, will be called a

species (eidos) of genus (G). In theory two species

within thè same genus can always be deformed one

into thè other in a continuous way (*). It can be ar-

gued that this notion, valid for man, is also to some

extent present in thè animai psyche. For man it is al¬

ways possible to shift from one colour to another wi¬

thout quitting thè space of colour measurement. But

(unless one is under thè influence of mescaline or

some similar drug) one cannot transform a colour

into a smeli or into a tactile sensation. There are two

basic genera: time, each instant of which is a species,

and one-dimensional Euclidean space (where each

point is a species).

If thè relative autonomy of thè nervous System

governing perception is sufficient to explain thè au¬

tonomy of thè fìve senses, thè same explanation is

not available for abstract concepts, thè adjectival

qualities of our languages. But at least w e may ima-

gine a topology of adjectival concepts allowing them

to be associated with a semantic distance, and by and

large, this semantic distance verifìes thè inequality of

thè triangle

d(BC) < d(BA) + d(AC)

provided qualities A, B, C belong to thè same genus.

Aristotle, in his Logics, laid down as a principle

that if w e have two genera, Gl and G2, either one of

them is a sub-genus of thè other (e.g. white man is a

sub-genus of man), or they are «incommunicable»:

Ouk estin eis allo genos metabasis (there is no way of

passing from one genus to thè other). This affirma-

tion led Aristotle to accept that all Science is reduced

to thè study of a genus, there is no universal Science.

But we may wonder whether thè articulation of sub¬

genera in a genus does not proceed from universal

mechanisms. I, for one, believe that thè model pro-

posed by catastrophe theory (thè cusp model) could

be a good candidate, particularly for thè transition

genus — species, object of zoological taxonomy.

This problematics surrounding thè incommunica-

bility of genera plays an essential part in thè question

of thè relation between quality and quantity, thè sub-

ject of this essay.

Even if we accept thè universality of thè cusp

model in thè division of a genus into its species,

there is nothing to show that thè different potentials

we have to consider between genera can be connect-

ed by a quantitative relation, of an algebraic nature

for example. Belief in thè possibility of expressing in

a quantitative way relations between different genera

has engendered semantic monsters in our everyday

vocabulary. Take thè paradigmatic example given by

thè quality-price ratio that serves in gastronomical

guide-books to rate different restaurants — thè direct,

positive side evaluating thè quality of thè setting and

cuisine, and thè opposite, negative side, concerned

with thè price. But thè idea of quantifying these ef-

fects by means of a quotient remains in thè realm of

mythology.

Now let’s come back to Biology. There is around

at thè moment a much-used but ill-defìned concept,

that of cellular type. It is agreed, or so I read recently

in a very serious journal, that there are about two

hundred types of celi in thè human body. But I have

seen no table of these types and have no idea of their

organizational modes. It was suggested to me that

thè mode of genome activation was an essential part

of this definition. But I suppose that thè old classical

designations of tissue (epithelium, mesenchyma,

free cells, etc.) continue to play a part in thè new ta¬

xonomy. However that may be, we have to believe

that this classification is of a «discrete», qualitative

and finite nature. It seems to me that this must have

some impact on an old evolutionary problem. Is

there gradualism, or, on thè contrary, catastrophism,

attending thè apparition of a given speciation? Dar¬

win contented himself with Lyell’s gradualism. Yet

we can hardly deny that there have appeared, at cer¬

tain times, very considerable innovations (a typical

example is thè apparition of thè amniotic egg in am-

phibians). If we look at thè graph constituted by cel¬

lular types in thè course of ontogenesis, we see that

new types must have come on thè scene from time to

time, even if, from a quantitative point of view, thè

clone so realized may have been very slight. Whence

a formally necessary response: There have indeed

been qualitative innovations, even if their immediate

quantitative effects remained unobtrusive. Quantita¬

tive gradualism stands to reason, after all — one can¬

not imagine a mother giving birth to offspring larger

than herself — but thè apparition of a new mode of

life made possible by qualitatively new types of cells

can turn this innovation into a subsequently notable

transformation in taxonomy.

In conclusion, I would like to draw attention to thè

unifying character of this definition of thè couple

Genus-Species. We shall cali «affect» all modifica-

tion of perceptive data in an individuai that is of a

clearly individuated nature. There exists then a rela¬

tion of equivalence between affects of subjective ori-

gin, which makes it possible to recognize whether

two affects are of thè same type (for example, pheno-

menological equivalence at two points in thè exter-

(*) Some genera, in Aristotle’s sense of thè word, obviously have a discontinuous matter. Take thè descendancy of

a single human ancestor, example given by Aristotle for thè entry Genos in his book Met A 28. In this case we have to

consider that thè matter of thè genus is engendered by thè generative dynamics represented by relations of filiation making

a connected space of thè human group.

QUALITATIVE AND QUANTITATIVE IN E V OLUTION ARY THEORY

117

nal medium observed). This last relation of equiva-

lence leads one, in thè case of thè observation of

living animals or dissected cadavers, to a classifica-

tion of equivalent parts by their aspect, Aristotle’s

homeomerous parts. W e are led to an objective defìni-

tion of biological organization: thè stratification of

thè organism into homeomerous parts. In a semi-al-

gebraic model, as suggested by Schiaparelli, this al-

lows us to recover thè homotopic diagrams of d’Arcy

Thompson and consequently to defìne Owen’s ho-

mology in a conceptually rigorous way. The decom-

position of a concept into genera and sub- genera be-

comes an operation (application to thè data of a locai

relation of phenomenological equivalence, or in al-

gebraic terms, a relation of equisingularity) similar in

nature to thè decomposition of an animai organism

into its «homeomerous» parts. In thè case of a con¬

cept, we have to classify its extension by identifying

its prototypical elements, centrally placed, and

throwing aberrant elements out toward thè periph-

ery. Categories are universal genera through which

such an analysis may be carried out.

Having defìned, in his study of living bodies, thè

notion of homeomerous parts characterized by thè

property of locai phenomenological equivalence bet-

ween two points of thè same stratum, Aristotle felt it

necessary to introduce also those parts which already

have specific names in our ordinary languages, thè

usuai body parts — in thè case of human beings:

head, neck, chest, belly, legs, arms and so on. Such

parts are usually formed by thè aggregation of sev-

eral (at least two) homeomerous parts, conveniently

limited. He called them anhomeomerous parts , thè

seats of active functions and operations (erga kai pra-

xeis). If homeomerous parts can be described by a

stratifìcation of semi-algebraic nature, these new

kinds of parts cannot be split up in thè same way.

Their breakdown fragments thè homeomerous stra-

ta. Take for instance thè inclusion thumb c hand.

The boundary between thumb n hand-minus-

thumb is realized in bony tissue by a well-defìned

smooth surface, thè phalanx-metacarpus joint. The

same is no longer true for any homeomerous part of

thè surrounding tissue (flesh, nerves, tendons, etc.).

And thè blood, contained in thè vascular System, is

not properly a homeomerous part because its ramify-

ing boundary shows signs of fractality ( Partibus Ani-

malium 565b 21-22). The observation that any func-

tionally active (anhomeomerous) part of thè human

body contains at least two kinds of tissues is one of

thè Philosopher’s most penetrating insights.

See for instance my astide:

R. Thom - Itinéraire pour une Science du détail. In

English: Itinerary for a Science of thè detail, Criti-

cism, voi. XXXII, n. 3, p. 311-390, 1990, Wayne State

University Press.

1

René Thom: Institut des Hautes Études Scientifìques 91440 Bures-sur-Yvette, FRANCE

Systematic Biology as an Historical Science

Memorie della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano

Volume XXVII - Fascicolo I - 1996

: *

*:

*

• •

: -

Adam Urbanek

The origin and maintenance of diversity:

a case study of Upper Silurian graptoloids

Abstract — Empirical studies on fossil material reveal certain features of thè fossil record which are of great importance

for thè generation and maintenance of biological diversity. This is particularly clear in respect of thè stem species

(lineages). Their persistence in time, combined with an ability for iterative speciation, accounts for many important events

responsive for recoveries and diversifications of thè fauna. Stem lineages provide a reliable test for thè conversation of

evolutionary potential in spite of thè numerous branching off of thè lineage. This may be called a historical experiment, as

it proves that deterministic factors, along with thè contingent ones, played an important role in evolution.

In thè reai course of evolution, as seen in thè fossil record, diversity is generateci due to so-called adaptive radiation.

As a rule, recovery and re-radiations start from indigeneous survivors from biotic crises. They are subject to a population

explosion combined with an increase of variation, both being related to an ecological release. This variation is later used as

raw material for speciation and transpecific evolution. The early phase of radiation is marked by thè paucity of lineages,

and thè presence, along with generalized or synthetic types (species or species groups), also of specialized lines of

evolution. The former produce long-lasting lineages and frequently are subject to secondary radiations, whilst thè latter

become extinct after some temporary success. In many groups of thè Graptoloidea, being thè dominating element of thè

macrozooplankton in thè Early Palaeozoic seas, evolutionary changes are concentrated on apertures of zooidal tubes. This

may reflect improvements of thè feeeding apparatus and feeding mechanisms. Trophic specialization is a golden thread of

thè evolution in this group. Production of as many character differences as possible, within a certain basic adaptive type,

enables thè subdivision of thè trophic niche and relaxation of competition between otherwise very similar species. Hence,

advanced representatives of particular lineages were usually K-strategists, while thè ancestral species bear more or less

distinct traces of an r-strategy. Seen from a historical perspective thè evolution of graptoloids looks as a process of diversity

and trophic specialization increase, punctuated by biotic crises. After each biotic crisis thè extermination of specialized

types was followed by a re-radiation from non-specialized survivors.

Inductive phylogeny

A study of thè history of fossil taxa and phyloge-

netic relations among them may be considered thè

core of any palaeontological programme. Studies in

other fìelds of palaeontology are, in one way or ano-

ther, related to this basic research programme — in

other words they are derivatives of thè historical and

phylogenetic approaches.

Dealing directly with remains of organisms of thè

past one can trace morphological changes in thè suc-

ceeding fossil populations from subsequent hori-

zons. A comparative anatomical analysis, combined

with morphometric (biometrie) methods, makes it

possible to measure certain parameters of evolution¬

ary change and to trace thè variation range, mean

value, and standard deviation, as well as to apply

more sophisticated methods (like multivariate analy¬

sis etc.). Essentially qualitative morphologies could

be transformed in this way into largely quantitative

data sets, which could later serve for discrimination

of species and other taxa. Such data, combined with

radiometrie age, may be instrumentai in thè evalua-

tion of certain parameters of thè evolutionary proc¬

ess which are not directly observable.

Studying fossil organisms enables thè application

of inductive methods to phylogeny, when phyloge¬

netic inferences are based largely on empirical data,

namely on thè observed direction of changes and

succession of chronodemes (fossil locai populations)

in time. This introduction of thè time factor and an

essential parallelism between morphological change

and time, limits considerably thè degree of subjec-

tive and speculative elements involved in phylo¬

genetic inferences. The application of an inductive

approach also increases thè probability of phyloge¬

netic inferences, and in thè case of densely-sampled,

numerically abundant and biometrically analysed

populations composed of well preserved remains —

they approach certaintly. Such highly reliable phylo-

genies constructed with thè use of thè inductive me-

thod were described among others also in graptoli-

tes. (e.g. Urbanek, 1963, 1966, 1970; see also Bulman

1971).

I apply thè term «inductive» to phylogeny merely

to stress thè importance of inferring generalized con-

clusions (on ancestry or relationship) from partial

faets concerning fossils, from thè changes observed

and their succession in time. I would rely on thè reai

course of events, established in thè above way, rather

than on considerations based on similarity and its

evaluation (homology). By using thè term «induc¬

tive» I would also like to emphasize thè significance

of bringing together and adducing disparate faets

making up thè reai history of fossils.

The research programme as advanced above

cannot be applied in every case — too frequently

thè incompletness of thè record makes thè use of

thè inductive approach impossible. However, thè in¬

ductive programme should be realized whenever

possible. It brings most interesting results, some of

which I am going to discuss below.

Considerations that will follow are based on thè

study of a single fossil group - thè graptolites. They

were colonial, marine hemichordates of thè Paleozo-

ic Era, related to Recent pterobranchs (represented

e.g. by Rhabdopleura ). Some were benthic and ses-

sile, but we will focus on «true graptolites», of thè

120

ADAM URBANEK

Fig. 1 - Early phase of monograptid radiation after thè lundgreni Event. Note thè population burst of thè only survivor,

Pristiograptus dubius (Suess) as indicated by a thick line, and its early schism into two main lineages. An important role was

played by Lobograptus? sherrardae as a generalized or synthetic species (from Koren’ & Urbanek).

order Graptoloidea. They were planktonic and in

most cases pelagic. The specialized Silurian mono¬

graptids had a simplifìed organization, and their co-

lonies were composed of a series of zooids budding

successively from each other and capable of secret-

ing individuai lodgings made of sclerotized collagen-

ous fibrils and called thecae (see Fig. 4, th2). The

overall morphology of thè skeleton of thè colony

(thè rhabdosome), as well as thè structural details of

thè thecae serve as thè basis for distinguishing a

number of genera and species. Displaying usually a

rapid evolution and frequently a world-wide distri-

bution, thè graptoloids («true graptolites») supply a

number of interesting instances of evolutionary

change.

The problem of stem species and thè nature

of historical experiments

One of thè most interesting taxa revealed by thè

study of phylogeny on fossil material are stem spe¬

cies. They may be operationally defìned as persistent

and conservative lineages producing, by means of

iterative speciation, some daughter species, but

otherwise showing a predominance of stasis or near-

stasis. A good example is Pristiograptus dubius

(Suess), a conservative monograptid species which

was thè only survivor from thè late Wenlock lundgre¬

ni Event. Soon afterward, it displayed a population

explosion, occurring probably in huge populations

(patches), which at thè same time displayed an in-

crease of both within-patch and between-patch varia-

tion. The role of numerical abundance and increased

variation was twofold: on one hand it served to ex-

pand thè niche, on thè other, it produced some fabric

that was used in later diversification into numerous

daughter species and resulted in adaptive radiation

(Fig. 1). The recovery of thè graptolite fauna in thè

late Wenlock (Homerian) and early Ludlow (Gors-

tian) was based on thè differentiation of this single

survivor. It became thè ancestor for thè bulk of later

graptolite faunas, all of which may be derived from

this single indigeneous relic species. The role of im-

migration was negligible (Koren’ and Urbanek, 1994,

in press).

Initially, there were only two daughter species,

which split from thè dubius stem line as a result of

thè so-called early schism (Fig. 1). One of them —

Pristiograptus praedeubeli gave rise to rather robust

monograptids such as Colonograptus and Saetograp-

tus (spinose monograptids of Gorstian stage). The

second, Pristiograptus idoneus produced, via a gene¬

ralized ancestral species Lobograptus? sherrardae,

such diverse forms as Neodiversograptus, Lobograp¬

tus and probably also Bohemograptus. They display

quite divergent trends of evolution but share a com¬

mon ancestry.

At thè same time thè dubius lineage continued to

exist without obvious morphological changes,

though much less numerous. In my opinion, it

should be treated as thè same species and even thè

same subspecies (Fig. 2). This practice opposes thè

cladistic approach to thè stem species — demanding

that thè ancestral species should be regarded as a

new one, after each speciation commenced from it.

THE ORIGIN AND MAINTENANCE OF DIVERSITY: A CASE STUDY OF UPPER SILURIAN GRAPTOLOIDS

121

Fig. 2 - Phylogenetic relations among Upper Silurian monograp-

tids, descendants of thè Pristiograptus dubius (Suess) stem spe-

cies. While thè conservative stem lineage continues without ob-

vious changes (thick line), its specialized derivatives (thin lines)

are subject to strong diversification and common extinction.

Note thè heterochronous appearance of similar morphological

types in Ludlow and Pridoli, namely Colonograptus and «neoco-

lonograptids». Asterisks denote additional speciation from thè

dubius stem lineage: * Pseudomonoclimacis dalejensis (Boucek) in

Gorstian time, ** Pseudimonoclimacis ìatilobus (Tseg.) and Pris¬

tiograptus fragmentalis (Boucek), both in Ludfordian. Wavy lines

indicate main extinction events. The early radiation phase is

shown at higher resolution on Fig. 1.

This is thè «nodal principle» or thè lineage concept

of species in cladistic systematics, according to which

thè temporal duration of a species is determined by

two processes of speciation, and species are «inter-

nodes» (segments of thè phylogenetic tree; Hennig,

1966: 20; Bonde, 1981: 23). Hence, a species should

be given different names before and after thè spe¬

ciation. Moreover, even strongly similar species

are given different binomials if they are situated

between different speciation events (nodes of thè

phylogenetic tree). This view is usually justified by

thè argument that because of thè speciation thè an-

cestral species completely changes its function in a

phylogenetic System. In relation to thè same dau-

ghter species, a given internode is considered to be

ancestral before speciation and a sister species, after

it. It seems obvious that one should not name thè

same entity now mother and now sister! In fact thè

latter argument is entirely unconvincing. It relies too

literally on thè analogy between genealogy and phy-

logeny — and this might be misleading. Giving such

species as Pristiograptus dubius a different name be¬

fore and after speciation because of purely formai

reasons, is of course possible, but undesireable, in

view of thè parsimony of nomenclature, and moreo¬

ver biologically unreasonable. Such a postulate also

pays no attention to thè fact that speciation does not

always break thè cohesion of thè ancestral lineage

(Simpson, 1951, Wiley 1978, 1979). In fact, stem spe¬

cies may survive one or more speciation events wi¬

thout a significant alteration. A good example is that

of sticklebacks ( Gasterosteus ), described by Bell

(1979), where morphologically divergent freshwater

species were established on Oceanie islands by thè

anadromous stock of Gasterosteus aculeatus, known

since thè Pliocene. Bell (1979: 87) is convinced that

repeated speciation has not caused sufficient (if any!)

alteration of thè parental species during approxima-

tely 10 Ma, «to warrant regarding thè latter as a suc-

cession of species».

A

Fig. 3 - Comparison of thè morphological evolution of bilateral

apertural lobes in thè proximal thecae of Ludlow colonograptids,

as illustrated by « Monograptus » praedeubeli Jaeger (Bt , praedeu-

beli zone) and Colonograptus colonus (Barrande) (B2, nilssoni

Zone), with Pridoli «neocolonograptidis» represented by Pseudo¬

monoclimacis parultimus (Jaeger) (C, , parultimus Zone), P. ulti-

mus (Perner) (C2, ultimus Zone) and P. lochkovensis (Pribyl)

(C3 , lochkovensis Zone). Final produets (B2 and C3) display a re-

markable resemblance, although they developed heterochro-

nously and independently from thè persistent stem lineage of

Pristiograptus dubius with straight apertural margins (A).

122

ADAM URBANEK

Fig. 4 - SEM micrographs showing proximal parts of A - Pristiograptus dubius (Suess), a conservative monograptid (Baltic

erratic boulder, parascanicus Zone, Gorstian) and its descendants: B - Colonograptus colonus (Barrande), (Baltic erratic

boulder, nilssoni Zone, Gorstian) as well as C - a «neocolonograptid» Pseudomonoclimacis lochkovensis (Pribyl) (deep

boring, East European Platform, lochkovensis Zone). D-E - structural details of apertural lobes in B and C respectively.

Taken with Philip XL 20 scanning electron microscope at 15 kV, from gold-platinum coated etched specimens. A-C x 50;

D-E x 150.

THE ORIGIN AND MAINTENANCE OF DIVERSITY: A CASE STUDY OF UPPER SILURIAN GRAPTOLOIDS

123

Another argument frequently quoted by cladists is

formulated in thè following way: so much variation

is lost in each speciation that this changes thè entire

evolutionary potential of thè ancestral species. Empi-

rical data do not confimi this assumption. P. dubius

can be quoted as a historical experiment of a kind.

After passing through a number of graptolite zones

of Gorstian and Ludfordian age, thè dubius stem li-

neage underwent a new (iterative) speciation in thè

early Pridoli time. The products were «neocolono-

graptids» — monograptids remarkably similar to thè

earlier Ludlow colonograptids (Fig. 3, 4), which had

become extinct in thè meantime (in thè leitwardinen-

sis Zone). Thus, provided that thè niche is empty,

thè dubius stem species was perfectly capable of spe-

ciating iteratively in very much thè same way as be-

fore. In other words, thè dubius stem lineage fea-

tured essentially thè same evolutionary potential

during thè Pridoli time (Fig. 3, C,-C3) as during thè

late Wenlock and Ludlow (Fig. 3, B,-B2), in spite of

thè numerous speciation events which occurred

from thè ancestral stock during this interval (Fig. 2).

The persistence of thè stem species and thè con-

servation of its evolutionary potential clearly contra-

dicts thè common conviction that speciation always

means a total reorganization of thè ancestral species.

What w e cali «an historical experiment» indicates

that at least in some cases such claims are contradict-

ed by thè data. Speciation events frequently do not

affect thè entire genetic pool of thè ancestral species,

but only a fraction of it. The entire genetic pool is af-

fected when daughter species appear according to

thè «dumbbell» model of speciation, as defined by

Mayr (1982), and when a parental species is suddivid-

ed into large derived portions. In fact, most of specia¬

tion events recorded among macrozooplankton be-

long to thè category of parapatric speciation (van der

Spoel, 1983; Boxshall, 1981). This mode of speciation

involved only peripheral populations of thè ancestral

species, which later became semiisolated. Hence, thè

genetic loss for thè entire System of thè parental spe¬

cies was negligible. When analysing thè Gasterosteus

case, Bell (1979: 85) has arrived at a conclusion that

«daughter speies neither carry away with them a sig-

nifìcant unique portion of thè species gene pool, nor

outcompete... or alter thè ecological niche of thè pa¬

rental species». The same was probably also true for

thè dubius lineage and expressed in thè preservation

of morphological spectrum and potential to change

(Fig. 4, B-E). It should also be noted that thè ecological

niche of thè dubius lineage, probably widened during

thè peak of numerical abundance, was later normalized

without any considerable alteration. In spite of numer¬

ous oscillations in thè prevailing morphotype of suc¬

cessive chronodemes, some samples of Pridoli age are

remarkably similar to those of lower Ludlow age.

The persistence of thè dubius stem lineage may

only be approximately estimated, because of thè re¬

lative scarcity of radiometrie dating for thè Upper Si-

lurian as well as a large margin of uncertainty of each

particular dating. Using thè dated stratigraphic scale

compiled by Odin and Odin (1990), one could esti¬

mate thè age of thè early schism as somewhat more

than 420 Ma, and thè appearance of first «neocolono-

graptids» as approximately 415 Ma (thè bottom of thè

Pridoli). Therefore thè dubius stem species preser-

ved its evolutionary potential intact for at least 5 Ma

and perhaps more!

An historical experiment - thè case

of spinose Monograptus

Another remarkable instance of a historical expe¬

riment is that of thè lobate-spinose monograptids of

late Wenlock and late Ludfordian age. The majority

of late Wenlock monograptids (M.flemingi, M. prio-

don) had hooked apertural lobes as well as paired lat-

eral spines (Fig. 5, B,-B2). Such monograptids beca¬

me extinct during thè lundgreni Event, and for some

five graptolite zones thè true monograptids - Mono¬

graptus (Monograptus) dissappeared from all known

sequences in thè epicontinental seas. They did not

reapper until thè nilssoni Zone, being represented by

Monograptus (M.) uncinatus Tullberg. In contrast to

thè late Wenlock forms it is provided with an apertu¬

ral lobe alone, without any spines (Fig. 5, ArA2) and

may be considered a derivative of thè ancient non-

specialized stock rather than a survivor of thè fauna

immediately preceding thè mass extinction which

occurred towards thè end of thè Wenlock. Mono¬

graptus (M.) uncinatus soon disappears but similar

forms reappear in thè late Ludfordian and thè early

Pridoli. Thus thè uncinatus lineage exhibits what is

known as a classical «Lazarus effect», a pehomenon

described by Jablonski (1986). After their final reap-

pearance, uncinatus- like monograptidis play a very

important role in Late Silurian and Early Devonian

faunas. The great comeback of thè true monograptids,

represented by thè uncinatus group, is one of thè most

remarkable features of late graptolite faunas. No

wonder that they re-occupied thè former Monograp¬

tus niche, which had been empty for some time, and

made some «attempts» to fili it completely by pro-

ducing again a lobate-spinose adaptive type, very si¬

milar to that encountered in thè Wenlock (Fig. 5,

CrC2). Their main representative Monograptus (M.)

spineus Tseg. may be derived from Monograptus (M.)

acer Tseg., through a transient link yet undescribed.

In this way we learn that thè Ludfordian lobate-spi¬

nose species appeared independently of thè earlier

ones. Yet, they mimic them in their overall appear¬

ance, except for certain details. While thè Wenlock

forms have lateral spines situated postero-laterally,

thè Ludfordian ones have them in thè antero-lateral

position (Fig. 5, B-C). Comparing them with thè an¬

cestral structure of Monograptus (M.) uncinatus one

may notice that thè Wenlock species have their spi¬

nes situated at point «x» and thè Ludfordian ones, at

point «y». This difference, however small, speaks for

a somewhat «defìcient» homology. Although in both

cases thè adaptive significance of thè apertural appa-

ratus thus attained is almost identical, minute details

provide evidence for their independent, iterative ori-

gin. These spines are not merely non-identical, but

they combine features of homolgy and homoplasy.

Using Remane’s (1956) widely accepted criteria of

homology, namely: (1) position in a structural Sys¬

tem, (2) specificity of structure, and (3) presence of

transitional stages, one could conclude that thè

structures in question are basically homologous.

This is because (1) in both cases spines are superim-

posed on thè apertural lobe and (2) made of thè same

skeletal tissue, however, (3) they are not related to

thè same ancestral species, and they diverged at a dif-

ferent time producing different morphoclines. Thus

we are dealing here with a border case between ho¬

mology and homoplasy, thè former being implied by

124

ADAM URBANEK

morphological criteria (1-2) of Remane (1956) and

thè latter by thè phylogenetic aspect (criterion 3). A

number of theoretical terms may be invoked here as

relevant to a great or smaller extent, but neither

seems fully adequate. As we are dealing here with

thè consequences of parallel evolution, structures in

question may be defìned as «homoiologous» (Piate,

1922; Remane, 1956). Usually their similarity is ex-

plained as a consequence of a certain potential deri-

ved from a common ancestor. This potential dispo-

ses them to change in a certain way, and they do so in

distinct lineages (canalized evolutionary potential;

Saether, 1983; Gosliner and Ghiselin, 1984). Struc¬

tures produced in parallel or iterative lineages may

reveal a deceptive combination of homology and ho-

meomorphy, frequently beyond thè resolving power

of comparative-anatomical methods.

The above situation implies a certain philosophy.

It is clear that thè uncinatus stock preserved its evolu¬

tionary potential to form not only thè apertural lobes

but also spines. I am talking about a «potential»

rather than about «tendencies» as proposed by

Simpson (1961) in his classical defmition of evolu¬

tionary species. A tendency is usually related to thè

internai factors of evolution, which produce change

independently of thè circumstances, whilst a poten¬

tial can manifest itself only under certain conditions.

I would also avoid such terms as «historical fate of

thè species» (as suggested by Wiley, 1978), which

may imply a predeterministic nature of evolutionary

change. G. G. Simpson usually viewed with caution

autogenetic interpretations of evolution. However,

when formulating his classical defmition of species

he seems to have forgotten about this danger.

The history and thè iterative origin of thè lobate-

spinose monograptidis have much in common with

thè frequently debated problem of contingency of

evolution, where «re-runs» of a certain sequence of

events inevitably produce a different result each

time. In our case, thè Wenlock sequence and thè

Ludfordian re-run produced fairly similar, although

not quite identical results. In recent debates thè em-

phasis is usually put on thè role of chance and on thè

unpredictability of results (Gould, 1989). The mono-

graptid case reveals thè role of deterministic factors

and thè essential repetition of results, although iden-

tity is not achieved. This increase in thè significance

of predictability is in an obvious way related to thè

amazing ability of thè stem lineages to sustain their

evolutionary potential through time in spite of nu-

merous iterative speciations from thè stem group.

The morphogenetic dispositions are contingent ra¬

ther than necessary but they persisi long enough to

produce thè iterations.

Fig. 5 - Comparison of apertural apparatus (Ai-A2) in Monograptus uncinatus Tullberg from thè nilssoni Zone (Ludlow,

Gorstian) representing a nonspecialized, ancestral type of structure, with late Wenlock (BrB2) and late Ludfordian (C,-C2)

lobate-spinose monograptids. All seen in ventral and lateral aspects; x, y, z, homological points on thè dorsal apertural

lobe. Note that lateral processes (lp) in late Wenlock forms were situated at x, while their analogues (alp, anterolateral proces-

ses) in Ludfordian forms were placed at y. Point z was transformed in thè latter group into a projecting edge (promontorium).

THE ORIGIN AND MAINTENANCE OF DIVERSITY: A CASE STUDY OF UPPER SILURIAN GRAPTOLOIDS

125

Adaptive radiations - generation and maintenance

of diversity

The history of thè Graptoloidea, planktonic grap-

tolites, abounded in biotic crises, which strongly re-

duced thè diversity of thè fauna and placed thè group

on thè brink of extinction. Since thè end of thè Ordo-

vician, at least six such major crises have been distin-

guished, after which a strongly impoverished fauna

displayed its ability to recover. As a rule, thè recovery

starts from indigeneous survivors which are subject to a

population burst and then to growing diversification.

The fossil record is complete enough to trace thè ex¬

tinction events and all thè successive stages of recov¬

ery. In extreme cases, only one or two relic species

undergo a population explosion producing huge pat-

ches of zooplankton. This is expressed taphonomi-

cally in thè mass abundance of their fossil remains in

thè sediments or bedding planes (thè so-called

«graptolite carpets»). Such a population burst may be

considered a direct response to thè ecological release

occurring due to thè elimination of competing spe¬

cies and relaxation of thè intra- as well as intergroup

selection pressure. On thè other hand, high numeri-

cal abundance creates suitable conditions for genera¬

tion of genetic variation. This conclusion, first ad-

vanced by E. B. Ford (1931), was later developed into

a common wisdom of evolutionary biology. No

doubt, such increased variation is later used as raw

material in both thè forthcoming speciation and

transpecific evolution.

Early phases of adaptive radiation are marked by a

paucity of lineages that split off thè ancestral species

(Fig. 1). Moreover, thè first representatives of thè

daughter lineages differ but little from thè parental

species. Nevertheless, they manifest different and

frequently quite divergent trends of evolution. There

appear numerous transients which frequently produ¬

ce a complete spectrum of variation, from thè stand¬

ard ancestral morphotype to thè morphotypes of

newly-formed species. Their presence is a remark-

able feature of this early phase of adaptive radiation.

Some of thè newly-appeared species, are forerunners

of further successful and long-lasting trends (Fig. 2),

some represent lines of precocious specialization

and become extinct after a short period of success.

The last named category produces blind alleys of

phylogeny, while thè former open avenues to much

longer prosperity. This is especially true of those spe¬

cies which deserve to be named synthetic or genera-

lized (terms frequently used in classical palaeontolo-

gy). They combine incipient traits of specializazion,

common to a number of descendant and completely

divergent trends (Fig. 1). Such ancestral species as

Lobograptus? sherrardae exhibit a great prospective

evolutionary potential, which, however, could be es-

timated only retrospectively, and cannot be predict-

ed from thè morphology and stratigraphic occurren-

ce of a given species. Some of thè descendant lines

are subject to secondary adaptive radiation. As far as

thè number of taxa produced is concerned, second¬

ary radiation may surpass thè primary one. However,

these radiations are usually variations on a theme, as

they represent modifìcations of a certain basic type

and exploit thè possibilities opened by thè given

adaptive type. Hence, their prospective potential is li-

mited as compared with primary adaptive radiation

(Fig. 2).

In many groups of graptoloids, and especially in

thè Monograptina, evolutionary changes were con-

centrated on certain key-features, namely on thè ap-

ertural region related to thè feeding apparatus of thè

zooid. The remaining structural features of thè colo-

ny were affected to a much lesser extent or remain

virtually unchanged. The evolution of such groups as

thè Cucullograptinae or Neocucullograptinae is a

graphic example of thè significance of trophic specia¬

lization for thè generation of diversity. The evolu¬

tion of particular lineages exhibits a remarkable ad-

vance in thè improvement of a particular adaptive

type (fig. 5). The replacement of sequential chronos-

pecies within such lineages accounts for a growing

degree of structural elaboration and possible sophis-

tication of thè feeding mechanism. This is an obvi-

ous instance of an anagenetic trend in thè phyletic

evolution of a single line of descent.

The co-existence of a number of species represent-

ing a basically similar adaptive type may be ensured

by thè generation of character differences between

related species. This seems to be particularly true of

plankton where, paradoxically, a number of con-ge-

neric species may co-exist sympatrically. Hutchinson

(1959, 1961) suggested an explanation of this «Para¬

dox of plankton», assuming that there exists a certain

safe limit of character differences in thè trophic

apparatus (a difference in size by a 1.3 ratio!). Such

a magnitude of differences allows a subdivision of

thè trophic niche and correspondingly a relaxation

of competition. At thè same time, such character

differences permit many species to co-exist and

avoid replacement, inevitable in view of thè action of

Gauze’s principle.

The family tree of many monograptids provides

convincing evidence that generation of differen¬

ces between closely related species with a largely

similar adaptive type played an important role in

evolution. This factor was also responsible for cla¬

dogenesi — diversification into numerous inde-

pendent evolutionary lines. One could hardly escape

thè conclusion that generation of character differen¬

ces was thè primary effect of evolutionary changes,

as differences per se had a positive effect on thè sur-

vival of thè species and thè stability of thè ecosystem

(Fig. 6).

The later and more advanced species of thè major¬

ity of thè lineages represent, in most graptoloid

groups, K-strategists (as defined by McArthur and

Wilson, 1967). They were adapted for exploitation of

a certain, rather narrowly defined fraction of food re-

sources and possess elaborated and sometimes bizar-

re apertural devices. However, in thè early stages of

recovery, thè ancestral species displayed a lack of

trophic specialization (frequently no apertural struc-

tures at all) as well as some other features of r-strate-

gies. Both thè transition from thè r- to thè K-strategy

and thè numerical increase of diversity and morpho-

logical complexity are side-effects of thè best known

adaptive radiations. This process was punctuated

from time to time by planetary disturbances of thè

environment resulting in mass extinctions. They, in

turn, were followed again by a recovery and re-radia-

tion (Fig. 2). From thè standpoint of evolutionary

ecology, thè Graptoloidea behaved as thè famous

Russian doli — «Van’ka-vstan’ka» (literally «Johnnie,

keep standing!»). It has a weight attached to its

rounded base causing it always to recover its stand-

126

ADAM URBANEK

Fig. 6 - Morphological effects od adaptive radiation in Upper Silurian monograptids of thè subfamily Cucullograptinae,

as exhibited by thè sicula and thè First theca of thè colony. 1 - Lobograptus progenitor Urbanek, thè stem species of

thè group; 2 - L. simplex Urbanek, thè centrai species within thè subfamily and a generalized ancestor for divergent lines;

3 - L. expectatus Urbanek, an advanced but stili symmetric lobograptid; 4 - L. scanicus parascanicus (Kuhne); 5 - L. scanicus

amphirostris Urbanek; 6 - L. scanicus scanicus (Tullberg); 7 - L. imitator Urbanek; 8 - L. invertus Urbanek; 9 - L. cirrifer Urba¬

nek; 10 - Cucullograptus hemiaversus Urbanek; 11 - C. aversus rostratus Urbanek; 12 - C. pazdroi Urbanek. Heavy arrows indi¬

cate a presumable direction of evolution in symmetric lobograptids, whilst thin arrows show thè same in other lineages.

Note that 4-9 display hypertrophy of thè right lobe and 10-12 display hypertrophy of thè left lobe, a - indicates thè obverse

(left) aspect of thè aperture in asymmetric species (after Urbanek 1966, modified).

THE ORIGIN AND MAINTENANCE OF DIVERSITY : A CASE STUDY OF UPPER SILURIAN GRAPTOLOIDS

127

ing position. However, after one of thè bends some-

thing got wrong with thè toy itself — it never rose up

again. These problems, however, are beyond thè

scope of thè present contribution.

Acknowledgements — Many thanks are due to thè

organizers of thè workshop (Francesco Scudo, Gio¬

vanni Pinna and Michael Ghiselin) for having invited

me to attend this important meeting. The initial ver-

sion of my paper, delivered during thè meeting, was

commented upon by Michael Ghiselin, David Wake,

Alessandro Minelli and Alberto Simonetta. Moreo-

ver, Ghiselin, Minelli and Cesare Baroni Urbani sent

their comments to thè second version of my paper.

I used their valuable comments to improve my con¬

tribution and I thank them all. I would also like to

thank my wife Irina Bagajewa-Urbanek for translat-

ing this paper into English.

REFERENCES

Bell M. A., 1971 - Persistence of ancestral-sister species. Syste-

matic Zoology, 28: 85-88.

Bonde N., 1981 - Problems of species concepts in palaeontology.

Proceedings of Int. Symp. Concepì. Meth. in Palaeontology,

Barcelona, 19-34.

Boxshall G. A., 1981 - Community structure and resource parti-

tioning-the plankton. In. P. L. Forey (Ed.) The Evolving Bio-

sphere, Cambridge, 143-156.

Bulman O. M. B., 1971 - Graptolithina. In: R. C. Moore (Ed.)

Treatise on Invertebrate Paleontology, V (2nd ed.). Boulder,

Col., 163 pp.

Ford E. B., 1931 - Mendelism and Evolution. London, 122 pp.

Gosliner T. M., Ghiselin M. T., 1984 - Parallel evolution in

opisthobranch gastropods. Systematic Zoology, 33: 255-274.

Gould S. J., 1989 - Wonderful Life. The Burgess Shale and thè Na¬

ture of History. New York, 347 pp.

Hennig W., 1966 - Phylogenetic Systematics. Urbana, III., 263 pp.

Jablonski D., 1986 - Causes and consequences of mass ex-

tinctions: a comparative approach. In: D. K. Elliot (Ed.).

Dynamics of Extinction, New York, 183-229.

Koren’ T. N., Urbanek A., 1994 - Adaptive radiation of mono-

graptids after thè late Wenlock crisis. Acta Palaeontologica

Polonica , 39: 137-167.

Mayr E., 1982 - Speciation and macroevolution. Evolution, 36:

119-132.

McArthur R. H., Wilson E. O., 1967 - The Theory of Island Bio-

geography. Princeton, 191 pp.

Odin G.-S., Odin C., 1990 - Echelle numerique des temps geolo-

giques. Geochronique, 35: 12-21.

Plate L., 1922 - Allgemeine Zoologie und Abstammungslehre,

I. G. Fischer. Jena.

Remane A., 1956 - Die Grundlagen des Naturlichen System, der

Vergleichenden Anatomie und der Phylogenetik. Akademis-

che Verlagsges., Leipzig, 364 pp.

Saether O., 1983 - The canalized evolutionary potential. Syste¬

matic Zoology, 32: 343-359.

Simpson G. G., 1951 - The species concept. Evolution, 5: 285-298.

Simpson G. G., 1961 - Principles of Animai Taxonomy. Columbia

Univ. Press., New York, 247 pp.

Spoel S. van der, 1983 - Patterns in plankton distribution and

thè relation to speciation: thè dawn of pelagic biogeo-

graphy. In: R. W. Sims, J. H. Price & P. E. S. Wholey

(eds.). Evolution, Time and Space: The Emergence of

thè Biosphere. System. Assoc., Special Volume, London, 23:

291-334.

Urbanek A., 1963 - On generation and regeneration of cladia in

some Upper Silurian monograptids. Acta Palaeontologica

Polonica, 8: 135-258.

Urbanek A., 1966 - On thè morphology and evolution of thè Cu-

cullograptinae. Acta Palaeontologica Polonica, 11: 291-544.

Urbanek A., 1970 - Neocucullograptinae n. subfam. (Grapto¬

lithina) - their evolutionary and stratigraphic hearing. Acta

Palaeontologica Polonica, 15: 163-388.

Wiley E. O., 1978 - The evolutionary species concept reconside-

red. Systematic Zoology, 27: 17-26.

Wiley E. O., 1979 - An annotated Linnaean hierarchy, with com¬

ments on naturai taxa and competing Systems. Systematic

Zoology, 28: 308-337.

*)

Adam Urbanek: Instytut Paleobiologii PAN, al. Zwirki i Wigury 93, PL-02-089 Warsawa, POLAND

Systematic Biology as an Historical Science

Memorie della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano

Volume XXVII - Fascicolo I - 1996

■

: •

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David B. Wake

Schmalhausen’s evolutionary morphology

and its value in formulating research strategies

Abstract — Schmalhausen (1884-1963) made important contributions to several biological fields, notably embryology

evolutionary morphology, and evolution. Had his important work on stabilizing selection been available to western

biologists at thè time of thè «evolutionary synthesis» it is likely that he would be seen as one of its important architects His

early work as an expenmental embryologist contributed to his development of thè concepts of norm of reaction and

phenotypic plasticity as important components of evolutionary studies. Brief examples from recent studies of limb and

brain evolution in amphibians show how his work retains relevance for formulating research programs.

It is my contention that thè great Russian biologist

1. 1. Schmalhausen (1884-1963), was far ahead of his

time in his approach to problems in evolutionary

morphology. Contemporaries such as Dobzhansky

(1949) knew and appreciated him, but he was mainly

ignored by other western biologists, even includ-

ing Waddington, whose work paralleled that of

Schmalhausen in some important respects. Here I

review some of Schmalhausen’s main contributions

and show how his approach has relevance for deve-

loping modern research strategies in evolutionary

morphology.

Elsewhere (Wake, 1986) I have presented an Over¬

View and perspective on one of thè two books by

Schmalhausen (Factors of Evolution, The Theory of

Stabilizing Selection, 1949) that have been translated

into English. It is regrettable that more of his work is

not readily accessible to western readers, for even

thè most famous of his books in Russian (Schmal¬

hausen, 1969) remains untranslated. Increased atten-

tion has been accorded to Schmalhausen recently,

including a biography by his daughter (Schmalhau¬

sen, 1988) and interpretations of his scientific ap¬

proach to evolutionary studies (Alien, 1991; Voro-

byeva, 1992). I present only some highlights, derived

from Schmalhausen’s own work and from thè sour-

ces cited above (and papers cited in turn by them)

that are of special relevance to points I will make in

this paper.

Schmalhausen and his Contributions

Ivan Ivanovitch Schmalhausen was a student of

thè famous comparative anatomist A. N. Severtsov,

one of thè flrst true evolutionary morphologists

(Adam, 1980). Severtsov was interested in generai

rules of morphological development and evolution¬

ary transitions in morphology; that is, in regularities,

repeated patterns and parallels between ontogeny

and phylogeny. These issues were united in a field

that he termed «phyloembryogenesis». Schmalhau-

sens’s earliest work dealt with comparative studies of

limb and fin development in anurans, urodeles,

mammals and fìshes (Schmalhausen, 1907, 1908a,

1908b, 1910, 1912), and his contributions have been

of lasting value.

Schmalhausen was educated as a comparative em¬

bryologist and anatomist, and he remained associat-

ed with these areas of inquiry throughout thè first

part of thè century. The early part of Schmalhausen’s

professional career was an intellectually stimulating

time for Russian evolutionary biology. He was a con-

temporary of Chetverikov, whose early studies of

geographic genetic variation led to a long-continued

tradition and strong point in Russian biology. This

was thè intellectual environment that also produced

Dobzhansky. A prevalent theme was that there was a

great store of genetic variation in populations and

that populations simply absorbed mutations that

carne along steadily. Also important was Vavilov, a

great botanist whose work is more appreciated now

than in thè past, and who studied thè evolutionary

origins of domesticated plants. Vavilov was espe-

cially interested in regularities in patterns of plant

evolution, and is responsible for thè so-called

«laws» of homologous series (e.g., Vavilov, 1922).

I consider Vavilov to be thè father of modern studies

of homoplasy.

It was perhaps inevitable that a morphologist

interested in evolution would also become inter¬

ested in thè genetic foundation of morphological

variation, and Schmalhausen became increasingly

recognized, within Russia, as a generai evolutionary

biologist. He succeeded his old professor as director

of an institute in Moscow in 1936, and eventually

became Professor of Darwinism in thè University of

Moscow.

It was Schmalhausen’s great misfortune to work

during a period of great politicai uncertainty and tu-

mult. Both Chetverikov and Vavilov suffered politi¬

cai ostracism, and Vavilov disappeared. Schmalhau¬

sen himself was denounced during thè period of thè

ascendency of Lysenko and attacks on mendelian ge-

netics in thè late 1940’s, and he was removed from

his professorship (Zirkle, 1949). He was partially re-

habilitated later, on condition that he restrict himself

to studies of comparative embryology and morpho¬

logy and avoid genetics. The laboratory he then de-

veloped in Moscow made important contributions to

our understanding of comparative morphogenesis of

vertebrates.

The work that introduced Schmalhausen to thè

English-speaking community of evolutionary bioio-

130

DAVID B. WAKE

gists is «Factors of Evolution», translated from thè

earlier Russian version and published in 1949. This

hook was written during thè Second World War,

when Russia was out of touch with developments in

thè West, and even its publication in Russian was de-

layed until 1947 (thè Russian version is dated 1946,

but Dobzhansky [in Schmalhausen, 1949] States that

it did not appear until 1947). So, when it reached

American and British scientists it appeared to be

dated, with few modern references. Despite a lauda-

tory introduction by Dobzhansky, thè book really

had no immediate impact. It did not even cite Simp-

son or Mayr, so one can imagine how it was received

by these scientists, who considered themselves to be

thè architects of «The New Synthesis» (Mayr and

Provine, 1980); it was largely ignored.

Many of thè topics addressed by Schmalhausen

are of great interest today: norms of reaction, pheno-

typic plasticity, morphological stasis, and morpholo-

gical transitions are just a few of thè major items

(e.g., Sultan, 1992). I think of his book as thè most

comprehensive and even thè most lasting of thè

great works of thè period of thè modern synthesis

(that is, of thè books published from thè late 1930’s

through thè 1950’s). Alien (1991) has characterized

Schmalhausen’s work as that of a true, practicing dia-

lectical materialist (as contrasted with a mechanistic

materialist such as R. A. Fisher and perhaps most

western evolutionary biologists). The fusion of men-

delian genetics with darwinian naturai selection led

to a focus on genes and to thè reduction of issues

once thought to be organismal in nature into com-

ponent parts. The generai assumption of thè mecha¬

nistic materialists was that thè whole is equal to thè

sum of its parts, with no emergent qualities. Thus, in

neodarwinism there is emphasis on environmental

change, and on atomistic phenomena that frequently

are seen as parts of a mosaic of separate and interact-

ing, but ultimately independent, parts. In contrast,

thè dialectical materialist position of Schmalhausen

(enjoying a current resurgence, although most prac-

titioners are unconscious of thè philosophical under-

pinning) sees thè parts so interconnected that they

cannot be studied separately (Sewell Wright certain-

ly would have been comfortable with this). Change is

seen as a fundamental part of any System; it is not

necessarily imposed by outside phenomena but ra-

ther is built into thè interaction of parts, that is, it is

an expected outcome of thè organization of thè Sys¬

tem. The internai forces of change can be under-

stood as interactions of factors that are fundamental-

ly in opposition, but are nonetheless components of

thè System. Thus, on thè one hand, heredity is con¬

servative, while on thè other, variation is inevitable

and radicai in its possibilities. Evolution is thè out¬

come of what might be viewed as thè opposing forces

of heredity and variation. Furthermore, quantitative

changes always lead eventually to qualitative change,

so that novelty is an expectation. This can be seen

most clearly in thè processes associated with allopa¬

tìe speciation, where quantitative changes eventual¬

ly result in thè qualitative change of reproductive in-

compatibility. In all of this, historical contigency

plays a centrai role.

Alien (1991) has argued that Schmalhausen was a

committed dialectician, not a cosmetic one who was

conforming to a prevailing politicai System. In sup-

port of this view, Alien cites Schmalhausen’s con-

tinuous emphasis on thè contradictory forces invol-

ved in evolution, and his attempt at a true synthesis

between genetics and evolution theory, on thè one

hand, and embryology (and I would add morpholo-

gy) on thè other. Schmalhausen’s dialectical ap-

proach is especially clear in his focus on stabilizing

and dynamic selection as opposing forces; in fact,

one can logically argue that Schmalhausen more

than anyone else fìrst presented a full theory of stabi¬

lizing selection. In his world view, stabilizing selec¬

tion simply had to be emphasized.

I assert that thè development and utilization of thè

concept of thè norm of reaction has been one of

Schamalhausen’s most lasting contributions. A

norm of reaction is thè range of phenotypic expres-

sion of a given genotype. Schmalhausen recognized

stable (genetically fixed, in essence, and highly pre-

dictable) and labile («morphoses» and modifìca-

tions) traits. Morphoses (or phenocopies, features

which are indicative of thè potential of thè develop-

mental System, and hence also predictable) and mo-

difìcations, which he thought of as at least potential-

ly adaptive, both usually fall outside thè norm of

reaction of a genotype, except that some categories

of modifications could be within thè norm. Stabi¬

lizing selection converts labile into stable traits.

Selection on morphogenetic processes leads to thè

internalization of external cues, which stabilizes

development and makes outeomes highly predict¬

able. Clearly there is a hierarchical component in

this. In a variable environment, norms of reaction

change constantly, as stabilizing selection does its

work. Viewed in a modern perspective, what is need-

ed is a phylogenetic interpretation of thè evolution

of norms of reaction, for then w e will be able to

reach a true synthesis of homoplasy and directional

evolution.

Schmalhausen used many examples to show that

he was thoroughly familiar with then-current genet¬

ics, evolutionary theory, development, comparative

anatomy, and paleontology. He attempted a synth¬

esis that was both prescient and extraordinarily per-

ceptive. Regrettably, a truly modern synthesis stili

eludes us, and it is unclear to me whether this is be-

cause w e lack sufficient empiricism (thè almost daily

discoveries in developmental genetics continue to be

stunning in their possible implications), or because

we cannot see thè forest for thè trees.

My own research has been influenced by that of

Schmalhausen in a number of ways, and I will cite

two examples that show how his perspectives shaped

my work. The fìrst of these focuses on trait evolu¬

tion, and indirectly relates to morphoses, modifìca-

tions, and norms of reaction. The second relates to

hierarchical issues in organismal and taxic evolution,

and thè relation between parts and wholes.

Limb Evolution in Urodeles

Some of Schmalhausen’s earliest work dealt with

limb development in salamanders. His interest was

mainly in morphogenesis, but he was strongly in¬

fluenced by thè classic comparative anatomy practi-

ced in Europe in thè early part of this century and

therefore framed his study phylogenetically. He was

especially interested in thè relation of parts to wholes

with respect to limbs, in particular, thè organization

SCHMALHAUSEN’S EVOLUTIONARY MORPHOLOGY AND ITS VALUE

131

of thè mesopodial region, thè carpus and tarsus. The

mesopodia of salamanders contain a number of ele-

ments that arise as mesenchymal condensations

which chondrify and, in some taxa, ossify. Develop-

ment of thè region involves segmentation and bifur-

cation of axes of condensation (for a modern review

see Shubin and Alberch, 1986). Two of these axes

arise as segmentations (preaxial) and bifurcations

(postaxial) from thè rudimentary distai long bones

(radius and ulna in thè forelimb; tibia and fibula in

thè hindlimb). These axes grow from a proximal ori-

gin distally during development. A third arises as an

independent distai condensation (preaxial), which

spreads postaxially, segmenting and bifurcating to

form thè digitai arch (ultimately giving rise to thè

distai mesopodials, thè metapodials and thè digits).

The three axes converge in thè centrai postaxial re¬

gion, where Schmalhausen noted a recurrent variant

pattern, thè appearance of an additional centrai ele-

ment (called by him mediale 3, and hence known to

workers in thè fìeld as «Schmalhausen’s m»). He ar-

gued that this element is in thè background, so to

speak, of thè generative dynamics of thè limb, and

that it can variously be present as a separate element,

as an amalgamation with a centrai tarsal, or as an

amalgamation with a distai tarsal. Thus, he was ex-

ploring generative rules of development and both

thè bounds on phenotypic expression and thè oppor-

tunities presented for thè evolution of novelty. This

research clearly influenced his later important work

on phenotypic plasticity, stabilizing selection, and

hierarchical issues in evolutionary biology.

Recently Neil Shubin and I have been exploring

patterns of variation in salamander limb develop¬

ment from a phylogenetic perspective. In one recent¬

ly completed study (coauthored with Andrew Craw-

ford) we examined a large series of specimens of thè

newt Taricha granulosa, collected from a single pond

in California that had unexpectedly frozen solid and

killed thè newts. We examined 452 skeletons, and

found that about 95% of thè forelimbs and 89% of thè

hindlimbs has thè expected, «standard» organiza-

tional pattern of thè mesopodials. An enormous

number of combinations fusion or separation of thè

seven carpai and nine tarsal elements can be concei-

ved, but we encountered only 21 carpai and eleven

tarsal patterns. We found that five patterns were bila¬

terali symmetrical, which implies an organismal

basis (as opposed to a locai developmental irregular-

ity). By far thè most common of these patterns, both

absolutely and in a symmetrical state, was Schmal-

hausens’s m (in 5.4% of hindlimbs, and as a symme¬

trical pattern in both hindlimbs in 2.0% of indivi¬

duai). A phylogenetic analysis disclosed that thè

presence of m as a discrete element restores an an-

cestral character, found both in fossil temnospondyls

and in basai outgroups among salamander taxa.

Thus, m is a phylogenetic atavism, thè reappearance

of a trait characteristic of ancestral taxa. One other

symmetrical state also is an atavism. The three re-

maining symmetrical States duplicate patterns found

J elsewhere among urodeles either as rare variants or

' as fixed, novel, apomorphic States. Interestingly, m

plays a role in three of thè five most common pat¬

terns, either as a free-standing atavism or as a part of

an amalgamation that has biomechanical and hence

possibly adaptive significance. The apomorphies are

morphological novelties that have been related to

both developmental and adaptive processes (e.g.,

Wake, 1991). The criticai point is that all of thè va¬

riants are familiar; evolution tends to run in grooves,

with generative processes channeling phenotypic ex¬

pression. The bounded patterns of variation are thè

manifestation of a combination of phylogenetic his-

tory and developmental constraints. What ultimately

becomes fixed in a clade may well represent thè

working of naturai selection on thè underlying va¬

riation. The variant patterns appear as complete and

integrated alternative States, and thè selection pres-

sures leading to their fìxation could be very weak.

Once fixed, thè new patterns might be very import¬

ant, and in hindsight viewed as key innovations

which open new possibilities for evolutionary diver-

sifìcation (Larson et al., 1981; Wake and Larson,

1987; Wake, 1991).

Brain Evolution in Urodeles

Brains of salamanders historically have been

viewed as very generalized, and many neuroanato-

mists have referred to them as primitive. Others have

observed that they appear to be developmentally

relatively undifferentiated. However, there clearly

is something wrong with this observation, for in

many respects thè brains of chondrichthyans and

even those of petromyzontids are anatomically more

complex than those of salamanders. Furthermore,

several parts of thè teleost brain are vastly more

complex (e. g., thè cerebellum) than those of sa¬

lamanders. So, on phylogenetic grounds it is clear

that thè salamander brain is secondarily simplifìed

(Roth et al., 1993). In collaboration with G. Roth,

K. Nishikawa and others in their laboratories and

mine, we have been exploring thè reasons for this

simplification. It now seems clear that salamanders

are, in essence, caught in a phylogenetic and evolu¬

tionary trap. On thè one hand, they have extraordi-

narily large genomes, and having large genomes

means having large cells (Session and Larson, 1987.

On thè other hand, they are relatively small vertebra-

tes, and some of them are very small, perhaps thè

smallest tetrapods; this means that they have to pro¬

duce a complicated brain in a small space with very

large cells, and so something has to give. Neuron

packing is nearly as tight as it can be, and there is

little glial matter in thè smallest species (Roth et al.,

1990). The extreme cases of brain simplification

are found in salamanders of very small size (sev¬

eral species mature at body sizes less than 20 mm)

with thè largest genomes and cells. I have argued

(Hanken and Wake, 1993) that these small salaman¬

ders are biologically very much smaller than their

metric size implies, and when comparing taxa that

vary greatly in celi size, metric size inappropriately

and inadequately expresses biological size. Recently

we found that large genomes also mean morpholo¬

gical simplification of brain organization in two

other vertebrate clades, frogs and dipnoans (Roth

et al., 1994).

Brain organization in amphibians illustrates well

thè signifìcance of hierarchical factors (relation of

molecules, cells, organs and organisms) in evolution.

In addition, it shows how misleading it can be to con-

sider isolated parts outside of thè context of thè

whole. It is far more parsimonious to interpret thè

132

DAVID B. WAKE

overall organization of thè brain as being directly

related to celi size than it is to generate a series of

separate explanations for thè simplifìed organization

of one part after thè other.

Summary

Schmalhausen developed a perspective toward

evolutionary biology that is resoundingly modern.

He was a through-going darwinian, who understood

naturai selection theory and applied externalist per-

spectives throughout his career, but at thè same time

he was a well trained embryologist who understood

thè nature of generative rules and interpreted them

in an evolutionary framework. Evolutionary deve-

lopmental biology is only one field that owes

Schmalhausen a debt. His contributions were gen¬

erai, in that they dealt with all of organismal evolu¬

tionary biology, and I believe that they will be some

of thè most long-lasting contributions from thè per-

iod of thè late 1930’s and early 1940’s. During thè last

decade, and continuing to thè present, there has

been a rebirth of interest in many of thè issues

Schmalhausen first raised.

Acknowledgments — I thank thè organizers of

this conference for thè invitation to participate,

and my colleagues N. Shubin, G. Roth and

K. Nishikawa for permission to cite unpublished

work. I appreciate constructive comments on

thè manuscript by S. Deban, M. Ghiselin, E. Jo-

ckusch, M. Mahoney, A. Minelli, C. Schneider

and M. Wake. My research is supported by thè

National Science Foundation and thè Gompertz

Professorship.

REFERENCES

Adams M., 1980 - Severtsov and Schmalhausen: Russian mor-

phology and thè evolutionary synthesis. In: E. Mayr and

W. B. Provine, eds., The Evolutionary Synthesis. Harvard

Univ. Press, Cambridge, Mass: 193-225.

Allen G. E., 1991 - Mechanistic and dialectical materialism in

20th century evolutionary theory: thè work of Ivan I.

Schmalhausen. In: L. Warren and H. Koprowski, eds., New

Perspectives on Evolution. Wiley-Liss, New York: 15-36.

Dobzhansky T., 1949 - Foreword to Factors of Evolution, by

I. I. Schmalhausen. Blakiston, Philadelphia: 327 pp.

Larson A., Wake D. B., Maxson L. R. and Highton R., 1981 - A

molecular phylogenetic perspective on thè origins of mor-

phological novelties in thè salamanders of thè tribe Pletho-

dontini (Amphibia, Plethodontidae). Evolution, 35:405-422.

Mayr E. and Provine W. B., 1980 - The Evolutionary Synthesis.

Harvard Univ. Press, Cambridge, Mass.: 487 pp.

Roth G., Rottluff B., Grunwald W., Hanken J. and Linke R.,

1990 - Miniaturization in plethodontid salamanders (Cauda¬

ta: Plethodontidae) and its consequences for thè brain and

visual System. Biol. J. Linn. Soc., 40:165-190.

Roth G., Nishikawa K. C., Naujoks-Manteuffel C., Schmidt

A. and Wake D. B., 1993 - Paedomorphosis and simplifica-

tion in thè nervous System of salamanders. Brain, Behavior

and Evolution, 42:137-170.

Roth G., Blanke J. and Wake D. B., 1994 - Celi size predicts

morphological complexity in thè brains of frogs and sala¬

manders. Proc. Nati. Acad. Sci., USA, 91: 4796-4800.

Schmalhausen I. I., 1907 - Die Enwicklung des Skelettes der

vordern Extremitàt der anuren Amphibien. Anat. Anz., 31:

177-187.

Schmalhausen I. I., 1908 a - Die Enwicklung des Skelettes der

hinteren Extremitàt der anuran Amphibien. Anat. Anz.,

33:337-344.

Schmalhausen 1. 1., 1908 b - Zur Morphologie des Saugertierfus-

ses. Anat. Anz., 33:373-378.

Schmalhausen 1. 1., 1910 - Die Entwicklung des Extremitàtens-

kelettes von Salamandrella kayserlingii. Anat. Anz., 37:

431-446.

Schmalhausen I. I., 1912 - Zur Morphologie der unpaaren Flos-

sen. I. Die Entwicklung des Skelettes und der Muskulatur der

unpaaren Flossen der Fische. Z. wiss. Zool., 100: 509-587.

Schmalhausen 1. 1., 1917 - On thè extremities of Ranidens sibiri-

cus Ressi. Rev. Zool. Russe, 2:129-135.

Schmalhausen 1. 1., 1949 - Factors of Evolution, The Theory of

Stabilizing Selection. Blakiston, Philadelphia: 327 pp.

Schmalhausen I. I., 1968 - The Origin of Terrestrial Vertebra-

tes. Academic Press, New York: 314 pp.

Schmalhausen I. I., 1969 - Problems of Darwinism. Nauka, Li-

ningrad: 493 pp. (in Russian).

Schmalhausen O. I., 1988 - Ivan Ivanovich Schmalhausen.

Nauka, Moscow: 256 pp. (in Russian).

Sessions S. K. and Larson A., 1987 - Developmental correlates

of genome size in plethodontid salamanders and their impli-

cations for genome evolution. Evolution, 41: 1239-1251.

Shubin N. and Alberch P., 1986 - A morphogenetic approach to

thè origin and basic organization of thè tetrapod limb. Evol.

Biol, 20:319-387.

Shubin N., Wake D. B. and Crawford A. J., 1995 - Predictable

morphological variation in thè limbs of Taricha granulosa

(Caudata: Salamandridae): evolutionary and phylogenetic

implications. Evolution.

Sultan S. E., 1992 - Phenotypic plasticity and thè Neo- Darwi¬

nian legacy. Evol. Trends in Plants, 6: 61-71.

Vavilov N., 1922 - The law of homologous series in variation.

Genetics, 12: 47-89.

Vorobyeva E., 1992 - In thè search for thè new strategy of evolu¬

tionary synthesis. Rivista di Biologia, 85: 213-224.

Wake D. B., 1986 - Foreword, 1986. Reprinted edition of Schmal¬

hausen 1. 1. Factors of Evolution. University of Chicago Press,

Chicago: 327 pp.

Wake D. B., 1991 - Homoplasy: thè result of naturai selection or

evidence of design limitations? Am Nat., 138: 543- 567.

Wake D. B. and Larson A., 1987 - Multidimensional analysis of

an evolving lineage. Science, 238: 42-48.

Zirkle C. (ed.), 1949 - Death of a Science in Russia. Univ. Penn¬

sylvania Pres, Philadelphia: 319 pp.

David B. Wake: Department of Integrative Biology and Museum of Vertebrate Zoology,

University of California, Berkeley, CA 94720 - 3160 U.S.A.

Systematic Biology as an Historical Science

Memorie della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano

Volume XXVII - Fascicolo I - 1996

133

INDEX

Introduction .

Systematic biology as an historical Scien¬

ce: discussion and retrospect by Michael

Ghiselin .

E. Nicholas Arnold - The role of biologi-

cal process in phylogenetics with exam-

ples from thè study of lizards ....

Yves Bouligand - Morphological singula-

rities and macroevolution .

Mikhail A. Fedonkin - The Precambrian

fossil record: new insight of life . . .

Michael T. Ghiselin - Charles Darwin,

Fritz Miiller, Anton Dohrn and thè origin

of evolutionary physiological anatomy .

James R. Griesemer - Some concepts of

historical Science .

Alessandro Minelli - Some thought on ho-

mology 150 years after Owen’s defmition

Robert J. O’Hara - Trees of history in sys-

tematics and philology .

--

»

Volume XIV

Volume XX

- Venzo S., 1965 - Rilevamento geologico dell’anfiteatro

morenico frontale del Garda dal Chiese all’Adige, pp. 1-82,

11 figg., 4 tavv., 1 carta.

1 - Pinna G., 1966 - Ammoniti del Lias superiore (Toarciano)

dell’Alpe Turati (Erba, Como). Famiglia Dactyliocerati-

dae. pp. 83-136, 4 tavv.

''] - Dieni I., Massari F. e Montanari L., 1966 - Il Paleogene

dei dintorni di Orosei (Sardegna), pp. 137-184, 5 figg.,

8 tavv.

I - Cornaggia Castiglioni O., 1971 - La cultura di Reme-

delio. Problematica ed ergologia di una facies dell’Eneoli¬

tico Padano, pp. 5-80, 2 figg., 20 tavv.

II - Petrucci F., 1972 - Il bacino del Torrente Cinghio (Prov.

Parma). Studio sulla stabilità dei versanti e conservazione

del suolo, pp. 81-127, 37 figg., 6 carte tematiche.

Ili - Ceretti E. & Poluzzi A., 1973 - Briozoi della biocalcare-

nite del Fosso di S. Spirito (Chieti, Abruzzi), pp. 129-169,

18 figg., 2 tavv.

Volume XV

- Caretto P. G., 1966 - Nuova classificazione di alcuni

Briozoi pliocenici, precedentemente determinati quali

Idrozoi del genere Hydractinia Van Beneden. pp. 1-88,

27 figg., 9 tavv.

- Dieni I. e Massari F., 1966 - Il Neogene e il Quaternario

dei dintorni di Orosei (Sardegna), pp. 89-142, 8 figg., 7 tavv.

1 - Barbieri F., Iaccarino S., Barbieri F. & Petrucci F.,

1967 - Il Pliocene del Subappennino Piacentino-Parmen¬

se- Reggiano, pp. 143-188, 20 figg., 3 tavv.

Volume XVI

- Caretto P. G., 1967 - Studio morfologico con l’ausilio del

metodo statistico e nuova classificazione dei Gasteropodi

pliocenici attribuibili al Murex brandaris Linneo, pp. 1-60,

1 fig., 7 tabb., 10 tavv.

I - Sacchi Vialli G. e Cantaluppi G., 1967 - 1 nuovi fossi¬

li di Gozzano (Prealpi piemontesi), pp. 61-128, 30 figg.,

8 tavv.

ili - Pigorini B., 1967 - Aspetti sedimentologici, del Mare

Adriatico, pp. 129-200, 13 figg., 4 tabb., 7 tavv.

Volume XVII

| - Pinna G., 1968 - Ammoniti del Lias superiore (Toarciano)

dell’Alpe Turati (Erba, Como). Famiglie Lytoceratidae,

Nannolytoceratidae, Hammatoceratidae (excl. Phymatoce-

ratinae ), Hildoceratidae (excl. Hildoceratinae e Bouleicera-

tinae). pp. 1-70, 2 tavv. n.t., 6 figg., 6 tavv.

H - Venzo S. & Pelosio G., 1968 - Nuova fauna a Ammonoidi

dell’Anisico superiore di Lenna in Val Brembana (Berga¬

mo). pp. 71-142, 5 figg., 11 tavv.

il Pelosio G., 1968 - Ammoniti del Lias superiore (Toarcia¬

no) dell’Alpe Turati (Erba, Como). Generi Hildoceras,

Phymatoceras, Paroniceras e Frechieìla. Conclusioni gene¬

rali. pp. 143- 204, 2 figg., 6 tavv.

Volume XVIII

[

il

- Pinna G., 1969 - Revisione delle ammoniti figurate da

Giuseppe Meneghini nelle Tavv. 1-22 della « Monographie

des fossiles du calcaire rouge ammonitique » (1867-1881).

pp. 5-22, 2 figg., 6 tavv.

- Montanari L., 1969 - Aspetti geologici del Lias di Gozza¬

no (Lago d’Orta). pp. 23-92, 42 figg., 4 tavv. n.t.

- Petrucci F., Bortolami G. C. & Dal Piaz G. V., 1970 -

Ricerche sull’anfiteatro morenico di Rivoli-Avigliana

(Prov. Torino) e sul suo substrato cristallino, pp. 93-169,

con carta a colori al 1:40.000, 14 figg., 4 tavv. a colori e 2 b.n.

Volume XIX

GL-

Cantaluppi G., 1970 - Le Hildoceratidae del Lias medio

delle regioni mediterranee - Loro successione e modifi¬

cazioni nel tempo. Riflessi biostratigrafici e sistematici.

pp. 5-46, con 2 tabelle nel testo.

Pinna G. & Levi-Setti F., 1971 - I Dactylioceratidae del¬

la Provincia Mediterranea ( Cephalopoda Ammonoidea).

pp. 47- 136, 21 figg., 12 tavv.

Pelosio G., 1973 - Le ammoniti del Trias medio di Askle-

pieion (Argolide, Grecia) - 1. Fauna del «calcare a Ptychi-

tes» (Anisico sup.). pp. 137-168, 3 figg., 9 tavv.

Volume XXI

I - Pinna G., 1974 - 1 crostacei della fauna triassica di Cene in

Val Seriana (Bergamo), pp. 5-34, 16 figg., 16 tavv.

II - Poluzzi A., 1975 - 1 Briozoi Cheilostomi del Pliocene del¬

la Val d’Arda (Piacenza, Italia), pp. 35-78, 6 figg., 5 tavv.

Ili - Brambilla G., 1976 - I Molluschi pliocenici di Villal-

vernia (Alessandria). I. Lamellibranchi. pp. 79-128, 4 figg.,

10 tavv.

Volume XXII

I - Cornaggia Castiglioni O. & Calegari G., 1978 - Cor¬

pus delle pintaderas preistoriche italiane. Problematica,

schede, iconografia, pp. 5-30, 6 figg., 13 tavv.

II - Pinna G., 1979 - Osteologia dello scheletro di Kritosaurus

notabilis (Lambe, 1914) del Museo Civico di Storia Na¬

turale di Milano ( Ornithischia Hadrosauridae). pp. 31-56,

3 figg-, 9 tavv.

Ili - Biancotti A., 1981 - Geomorfologia dell’Alta Langa (Pie¬

monte meridionale), pp. 57-104, 28 figg., 12 tabb., 1 carta ft.

Volume XXIII

I - Giacobini G., Calegari G. & Pinna G., 1982 - I resti

umani fossili della zona di Arena Po (Pavia). Descrizione

e problematica di una serie di reperti di probabile età

paleolitica, pp. 5-44, 4 figg., 16 tavv.

II - Poluzzi A., 1982 - 1 Radiolari quaternari di un ambiente

idrotermale del Mar Tirreno, pp. 45-72, 3 figg., 1 tab., 13 tavv.

Ili - Rossi F., 1984 - Ammoniti del Kimmeridgiano superiore

Berriasiano inferiore del Passo del Furio (Appennino

Umbro-Marchigiano), pp. 73-138, 9 figg., 2 tabb., 8 tavv.

Volume XXIV

I - Pinna G., 1984 - Osteologia di Drepanosaurus unguicau-

datus, lepidosauro triassico del sottordine Lacertilia.

pp. 7-28, 12 figg., 2 tavv.

II - NosottiS., Pinna G., 1989 -Storia delle ricerche e degli stu¬

di sui rettili Placodonti. Parte prima 1830-1902. pp. 29-84,

24 figg., 12 tavv.

Volume XXV

I - Calegari G., 1989 - Le incisioni rupestri di Taouardei

(Gao, Mali) - Problematica generale e repertorio iconogra¬

fico. pp. 1-14, 9 figg., 24 tavv.

II - Pinna G. & Nosotti S., 1989 - Anatomia, morfologia

funzionale e paleoecologia del rettile placodonte Psepho-

derma alpinum Meyer, 1858. pp. 15-50, 18 figg., 9 tavv.

Ili - Caldara R., 1990 - Revisione tassonomica delle specie

paleartiche del genere Tychius Germar (Coleoptera

Curculionidae). pp. 51-218, 575 figg.

Volume XXVI

I - Pinna G., 1992 - Cyamodus hildegardis Peyer, 1931 (Repti-

lia, Placodontia). pp. 1-21, 23 figg.

II - Calegari G. a cura di, 1993 - L’arte e l’ambiente del Saha¬

ra preistorico: dati e interpretazioni, pp. 25-556, 647 figg.

Ili - Andri E. e Rossi F., 1993 - Genesi ed evoluzione di frangen¬

ti, cinture, barriere ed atolli. Dalle stromatoliti alle comunità

di scogliera moderne, pp. 559-610, 49 figg., 1 tav.

Le Memorie sono disponibili presso la Segreteria della Società Italiana di Scienze Natu

Museo Civico di Storia Naturale, Corso Venezia 55 - 20121 Milano

MEMORIE

MCZ

Volume XXVII -

libra ?y

JU'l 0 8 J998

Fascicolo II

Harvard

- VWVERSlTy

della Società Italiana

di Scienze Naturali

e del Museo Civico

di Storia Naturale di Milano

STUDI GEOBOTANICI ED ENTOMOFAUNISTICI

NEL PARCO REGIONALE DEL MONTE BARRO

A cura di

CARLO LEONARDI E DAVIDE SASSI

MILANO 17 DICEMBRE 1997

Elenco delle Memorie della Società Italiana di Scienze Naturali

e del Museo Civico di Storia Naturale di Milano

Volume I

I - Cornalia E., 1865 - Descrizione di una nuova specie dei

genere Felis: Felis jacobita (Corn .).9 pp., 1 tav.

II - Magni-Griffi E, 1865 - Di una specie d 'Hippolais nuova

per l’Italia. 6 pp., 1 tav.

Ili - Gastaldi B., 1865 - Sulla riescavazione dei bacini lacustri

per opera degli antichi ghiacciai. 30 pp., 2 figg., 2 tavv.

IV - Seguenza G., 1865 - Paleontologia malacologica dei terre¬

ni terziarii del distretto di Messina. 88 pp., 8 tavv.

V - Gibelli G., 1865 - Sugli organi riproduttori del genere Ver¬

rucaria. 16 pp., 1 tav.

VI - Beggiato F. S., 1865 - Antracoterio di Zovencedo e di

Monteviale nel Vicentino. 10 pp., 1 tav.

VII - Cocchi I.,1865 - Di alcuni resti umani e degli oggetti di

umana industria dei tempi preistorici raccolti in Toscana.

32 pp., 4 tavv.

Vili - Targioni-Tozzetti A. 1866 - Come sia fatto l’organo che

fa lume nella lucciola volante dell’Italia centrale (Luciola

italica) e come le fibre muscolari in questo ed altri Insetti

ed Artropodi. 28 pp., 2 tavv.

IX - Maggi L., 1865 - Intorno al genere Aeolosoma. 18 pp., 2

tavv.

X - Cornalia E., 1865 - Sopra i caratteri microscopici offerti

dalle Cantaridi e da altri Coleotteri facili a confondersi con

esse. 40 pp., 4 tavv.

Ili - Marinoni G, 1868 - Le abitazioni lacustri e gli avanzi di

umana industria in Lombardia. 66 pp., 5 figg., 7 tavv.

IV - (Non pubblicato).

V - Marinoni C, 1871 - Nuovi avanzi preistorici in Lombar¬

dia. 28 pp., 3 figg., 2 tavv.

NUOVA SERIE

Volume V

I - Martorelli G., 1895 - Monografia illustrata degli uccelli

di rapina in Italia. 216 pp., 46 figg., 4 tavv.

Volume VI

I - De Alessandri G., 1897 - La pietra da cantoni di Rosi-

gnano e di Vignale. Studi stratigrafici e paleontologici. 104

pp., 2 tavv., 1 carta.

II - Martorelli G. 1898 - Le forme e le simmetrie delle mac¬

chie nel piumaggio. Memoria ornitologica. 112 pp., 63 figg.,

1 tavv.

Ili - Pavesi P, 1901- L’abbate Spallanzani a Pavia. 68 pp., 14

figg., 1 tav.

Volume VII

I - De Alessandri G., 1910 - Studi sui pesci triasici della Lom¬

bardia. 164 pp., 9 tavv.

Volume II

I - Issel A., 1866 - Dei Molluschi raccolti nella provincia di Pi¬

sa. 38 pp.

II - Gentilli A., 1866 - Quelques considérations sur l’origine

des bassins lacustres, àpropos des sondages du Lac de Co¬

me. 12 pp., 8 tavv.

Ili - Molon F., 1867 - Sulla flora terziaria delle Prealpi venete.

140 pp.

IV - D’Achiardi A., 1866 - Corollarj fossili del terreno num-

mulitico delle Alpi venete. 54 pp., 5 tavv.

V - Cocchi I., 1866 - Sulla geologia dell’alta Valle di Magra. 18

pp., 1 tav.

VI - Seguenza G., 1866 - Sulle importanti relazioni paleontolo¬

giche di talune rocce cretacee della Calabria con alcuni ter¬

reni di Sicilia e dell’ Africa settentrionale. 18 pp., 1 tav.

VII - Cocchi I., 1866 - L’uomo fossile nell’Italia centrale. 82 pp.,

21 figg., 4 tavv.

Vili - G aro vaglio S., 1866 - Manzonia cantiana, novum Liche-

num Angiocarporum genus propositum atque descriptum. 8

pp. 1 tav.

IX - Seguenza G., 1867 - Paleontologia malacologica dei terre¬

ni terziarii del distretto di Messina (Pteropodi ed Eteropo-

di). 22 pp., 1 tav.

X - Durer B., 1867 - Osservazioni meteorologiche fatte alla

Villa Carlotta sul lago di Como. ecc. 48 pp. 11 tavv.

Volume III

I - Emery C, 1873 - Studii anatomici sulla Vipera Redii. 16

pp., 1 tav.

II - Garovaglio S., 1867 - Thelopsis, Belonia, Weitenwebera et

Limboria, quatuor Lichenum Angiocarporum genera reco-

gnita iconibusque illustrata. 12 pp., 2 tavv.

Ili - Targioni-Tozzetti A., 1867 - Studii sulle Cocciniglie. 88

pp., 7 tavv.

IV - Claparède E. R. e Panceri R, 1867 - Nota sopra un Al-

ciopide parassito della Cydippe densa Forsk. 8 pp. 1 tavv.

V - Garovaglio S., 1871 - De Pertusariis Europae mediae

commentano. 40 pp., 4 tavv.

Volume IV

I - D’Achiardi A., 1868 - Corollarj fossili del terreno num-

mulitico dell’Alpi venete. Parte 11. 32 pp. 8 tavv.

II - Garovaglio S., 1868 - (Detona Lichenum genera vel adhuc

controversa, vel sedis prorsus incertae in systemate, novis

descriptionibus iconibusque accuratissimis illustrata. 18 pp.,

2 tavv.

I

II -

III -

I

II -

III -

I

II -

III -

I

ii-m-

i

ni -

Volume Vili

Repossi E., 1915 - La bassa Valle della Mera. Studi petro¬

grafia e geologici. Parte I .pp. 1-46, 5 figg., 3 tavv.

Repossi E., 1916 (1917) - La bassa Valle della Mera. Studi

petrografici e geologici. Parte IL pp. 47-186, 5 figg. 9 tavv.

Airaghi C, 1917 - Sui molari d’elefante delle alluvioni

lombarde, con osservazioni sulla filogenia e scomparsa di

alcuni Proboscidati.pp. 187-242, 4 figg., 3 tavv.

Volume IX

Bezzi M. 1918 - Studi sulla ditterofauna nivale delle Alpi

italiane, pp. 1-164, 7 figg. 2 tavv.

Sera G. L., 1920 - Sui rapporti della conformazione della

base del cranio colle forme craniensi e colle strutture della

faccia nelle razze umane. (Saggio di una nuova dottrina

craniologica con particolare riguardo dei principali cranii

fossili), pp. 165-262, 7 figg., 2 tavv.

De Beaux O. e Festa E., 1927 - La ricomparsa del Cin¬

ghiale nell’Italia settentrionale-occidentale, pp. 263-320, 13

figg., 7 tavv.

Volume X

Desio A., 1929 - Studi geologici sulla regione dell’Albenza

(Prealpi Bergamasche), pp. 1-156, 27 figg., 1 tav., 1 carta.

Scortecci G., 1937 - Gli organi di senso della pelle degli

Agamidi. pp. 157-208, 39 figg. 2 tavv.

Scortecci G., 1941- 1 recettori degli Agamidi. pp. 209-326,

Volume XI

Guigilia D., 1944 - Gli Sfecidi italiani del Museo di Mila¬

no (Hymen.). pp. 1-44, 4 figg., 5 tavv.

Giacomini V. e Pignatti S., 1955 - Flora e Vegetazione del¬

l’Alta Valle del Braulio. Con speciale riferimento ai pasco¬

li di altitudine, pp. 45-238, 31 figg., 1 carta.

Volume XII

Vialli V., 1956 - Sul rinoceronte e l’elefante dei livelli su¬

periori della serie lacustre di Leffe (Bergamo), pp. 1-70, 4

figg. 6 tavv.

Venzo S., 1957 - Rilevamento geologico dell’anfiteatro

morenico del Garda. Parte I: Tratto occidentale Gardone-

Desenzano. pp. 71-140, 14 figg., 6 tavv., 1 carta.

Vialli V., 1959 - Ammoniti sinemuriane del Monte Alben-

za (Bergamo), pp. 141-188, 2 figg., 5 tavv.

Studi geobotanici ed entomofaunistici

nel Parco Regionale del Monte Barro

a cura di

Carlo Leonardi

Sezione di Entomologia del Museo Civico di Storia Naturale di Milano

Davide Sassi

Collaboratore della Sezione di Entomologia del Museo Civico di Storia Naturale di Milano

Volume XXVII - Fascicolo II

17 Dicembre 1997

Memorie della Società Italiana di Scienze Naturali

e del Museo Civico di Storia Naturale di Milano

Museo Civico di Storia Naturale di Milano

corso Venezia, 55 - 20121 Milano

In copertina: Hypera vidua (Gené), disegno di Carlo Pesarmi.

Registrato al Tribunale di Milano al n. 6694

Direttore responsabile: Luigi Cagnolaro

Grafica editoriale: Michela Mura

Stampa Litografia Solari, Peschiera Borromeo - Dicembre 1997

137

INTRODUZIONE

Pur essendo di limitata estensione, il Parco del

Monte Barro, istituito dalla Regione Lombardia con

legge n. 78 del 16 settembre 1983, presenta un eleva¬

to interesse paesaggistico, geologico e naturalistico, in

particolare per quanto riguarda la flora (che com¬

prende numerosi endemismi) e la vegetazione.

In considerazione del fatto che, malgrado le pecu¬

liarità di questo Parco, la sua entomofauna risultava

praticamente sconosciuta, il Museo di Storia Natura¬

le di Milano si è posto l’obbiettivo di colmare, sia pur

in modo molto parziale, tale lacuna, effettuando in

quest’area, con un Contributo economico che il Par¬

co ha concesso alla Società Italiana di Scienze Natu¬

rali, una serie di raccolte negli anni 1989-1992. Il cen¬

simento faunistico, inizialmente finalizzato allo stu¬

dio dei Coleotteri Crisomelidi, è stato successiva¬

mente esteso ad altri gruppi di insetti, prevalente¬

mente o esclusivamente fitofagi, e ai ragni; sul cospi¬

cuo materiale raccolto si basano i lavori riuniti in

questo volume.

La nostra più viva riconoscenza va al Presidente e

al Direttore del Consorzio Parco Monte Barro, Prof.

Giuseppe Panzeri e Dr. Mauro Villa, che fin dall’ini¬

zio hanno appoggiato questo progetto.

Carlo Leonardi & Davide Sassi

Enrico Banfi, Gabriele Galasso & Davide Sassi

Aspetti floristico - vegetazionali del Monte Barro (Prealpi di

Lecco) in relazione all’area delle raccolte entomologiche

Riassunto - È stata studiata la flora di 9 stazioni di ambiente aperto nell’area del Parco del Monte Barro, con partico¬

lare riguardo per gli aspetti sistematico-tassonomici e corologici, dai quali è emersa la necessità di una revisione critica glo¬

bale della flora dell’intero territorio del Barro. Tale ricerca, servita di supporto a una più vasta indagine entomologica, ha

messo in evidenza aspetti della vegetazione, ufficialmente già noti, la cui interpretazione tuttavia potrà essere modificata o

migliorata da una più esatta conoscenza della flora; ciò anche nella prospettiva di acquisire le basi per una valutazione at¬

tendibile della biodiversità dell’intero territorio.

Abstract - Floristic and vegetational aspects of Mt. Barro (Italy, Lombardy, Prealps of Lecco) referring to thè area of

thè entomological sampling.

The flora of Mt Barro has been already investigated in thè past. A detailed floristic analysis of 9 meadow samples, re-

cently accomplished to support an entomological research which has been carried out by thè Naturai History Museum of

Milano, has evidenced interesting systematic-taxonomic and phytogeographic data. These observations lead thè authors to

consider thè necessity of examining again thè flora of thè whole territory on thè basis of modera knowledge and concepts,

especially in order to throw light on thè biodiversity and to determine its consistence. Furthermore thè vegetation is taken

into account to identify plant communities of sampling sites 1-8. Phytodiversity has been evaluated by using k-dominance

and diversity Shannon parameters.

Key words: Mt. Barro, Flora, Vegetation.

Il Monte Barro è un piccolo massiccio calcareo co¬

stituito prevalentemente da bancate di Dolomia nori-

ca, prospicente il versante sudorientale (Monte Mo-

regallo, Monte Rai, Corni di Canzo) dei rilievi del co¬

siddetto Triangolo Ladano e da questo separato me¬

diante l’ampia depressione alluvionale della Val Ma-

drera. Direttamente affacciato a oriente sul Lario lec-

chese, determina, con le sue pendici settentrionali, la

separazione di questo dal piccolo bacino di Garlate,

segnando l’inizio della valle dell’Adda postiariana.

È strutturalmente e morfologicamente connesso

con la piccola catena dei Colli Briantei che, allungata

in direzione nord-sud, costituisce per una quindicina

di chilometri lo spartiacque tra la valle del Lambro, a

occidente, e il corso dell’Adda, a oriente.

Pur non segnando, con la sua cima, una quota par¬

ticolarmente elevata, 922 m, il Monte Barro possiede

notevoli motivi di interesse geomorfologico e floristi¬

co. Durante le fasi di maggiore espansione dei ghiac¬

ci pleistocenici, l’intera superficie, a eccezione della

vetta e di alcune anticime poste a meridione di essa,

fu ricoperta dai ghiacci che, oltre a lasciare profonde

tracce sulla morfologia del territorio, cancellarono

ogni forma di vegetazione. L’attuale flora è dunque di

ì formazione recente, essendosi ricostituita a partire

dall’ultimo interglaciale.

La particolare posizione strategica del Monte

Barro, isolato dai rilievi circostanti e affacciato a sud

sulla vasta pianura briantea, fu sfruttata in epoca sto¬

rica dai Romani e, successivamente, dai Goti, che vi

costituirono vari nuclei di insediamento, databili al V-

VI sec. d. C., a tutt’oggi soltanto in parte esplorati.

Una serie di campagne di scavi, condotte regolar¬

mente in questi ultimi anni, ha portato al ritrovamen¬

to di reperti di notevole interesse.

Vista dunque la grande importanza, sia naturali¬

stica che storica, del Monte Barro, fu istituito con la

legge regionale 16 settembre 1983, n. 78 il Parco na¬

turale del Monte Barro, esteso su una superficie di

665 ettari.

Il Monte Barro è costituito da formazioni carbo-

natiche, la cui età si estende dal Norico al Cretaceo

medio-superiore, formanti una serie di quattro grosse

scaglie, disposte in successione nord-sud, subverticali

o immerse grosso modo verso nord (Nangeroni,

1972). Si tratta di una prima fascia di Dolomia Princi¬

pale (Norico), affiorante lungo le pendici settentrio¬

nali fino ad un piccolo sperone roccioso posto a quo¬

ta 858 m; segue una fascia di calcari marnosi del Re-

tico medio-inferiore, comprendente l’intera Val Faè e

la regione della vetta, a esclusione delle roccette del¬

la sommità, costituite di Dolomia Conchodon (Reti-

co superiore); una terza scaglia, ancora in Dolomia

norica, e infine una quarta fascia, costituente tutto il

basso versante meridionale, formata da calcari mar-

noso-selciferi liassici (Calcare di Moltrasio), calcari

del Giurassico sommitale e del Cretaceo inferiore

(Maiolica), e marne e arenarie del Cretaceo medio¬

superiore.

140

ENRICO BANFI. GABRIELE GALASSO & DAVIDE SASSI

Da un punto di vista strutturale, il rilievo è inte¬

ressato da due anticlinali parallele, ad asse disposto in

direzione NO-SE.Tra di esse trovasi la sinclinale del¬

la Val Faè, la quale, determinando l’affioramento dei

teneri calcari marnosi del Retico medio-inferiore, in¬

cassati tra la prima e la seconda scaglia di Dolomia

norica e separati da esse da due notevoli faglie, si tro¬

va in evidente concordanza morfologica con la topo¬

grafia.

La morfologia, oltre che delle condizioni struttu¬

rali e meteorologiche, risente in misura evidente, nei

depositi, nel modellamento e nell’erosione, dell’azio¬

ne sviluppata dai ghiacci. Depositi morenici, rocce le¬

vigate e striate, erratici anche di notevoli dimensioni,

generalmente in ghiandone della Val Masino, sono

rinvenibili fino a quota 874 m, segnando il limite del¬

la copertura dei ghiacci quaternari.

Potenti bancate di depositi fluvioglaciali, general¬

mente sottoposti a morenico, in gran parte trasfor¬

mati in cave di sabbia, sono visibili lungo i bassi ver¬

santi settentrionali. Piuttosto marcato appare in alcu¬

ne zone il modellamento carsico superficiale: per

esempio l’ampia balconata rappresentata dal Pian

Sciresa è probabilmente un vasto polje, costellato

nella zona meridionale da piccoli rilievi residuali a

sommità tondeggiante tipo hum.

Il clima

La massa idrica del lago di Lecco, unitamente a

quella degli altri corpi d’acqua più piccoli che cir¬

condano a est e a ovest il Monte Barro, determina il

carattere spiccatamente oceanico del clima di que¬

sto territorio. D’estate l’aria satura di umidità sale

nelle ore più calde e si espande raffreddandosi per

poi scaricarsi ostacolata dai contrafforti montuosi. I

dati termopluviometrici sono stati forniti dal Con¬

sorzio dell’ Adda, provengono dalla stazione di Olgi-

nate e si riferiscono al periodo 1981-1991 e alla quo¬

ta di 206 m s.l.m.; per quote superiori è necessaria

una piccola correzione lineare in abbassamento dei

valori termometrici secondo il gradiente termico al-

titudinale (Belloni & Pelfini, 1987). Le precipitazio¬

ni annuali sono tra le più elevate del settore preal¬

pino, 1.300 mm, con punte ben superiori in certe an¬

nate (1.678 mm nel 1984; il minimo si è avuto nel

1983 con 993 mm); anche l’umidità relativa è sempre

molto alta e nelle giornate più asciutte raramente

scende sotto il 70%. In compenso la media termica

annuale è di 13°C e la temperatura del mese più

freddo rimane leggermente sopra 3°C, sempre gra¬

zie all’effetto tamponante del sistema lacustre. Il

gradiente termico verticale negativo per il dislivello

206-922 m s.l.m. comporta un aumento con la quota

delle probabilità di gelate, nevicate e permanenza

del manto nevoso; il climogramma secondo Ba-

gnouls-Gaussen (Fig. 1) consente di inquadrare la ti¬

pologia climatica del nostro territorio nella regione

mesaxerica, sottoregione ipomesaxerica, tipo C(10)

insubrico (Tomaselli et al., 1973), caratterizzato fra

l’altro da assenza di deficit idrico estivo. Conside¬

rando che il Monte Barro è circondato da montagne

più alte (Corni di Ganzo, 1373 m; Moregallo, 1276 m;

Resegone, 1875 m; Albenza, 1250 m) costituenti la

barriera effettiva alle masse d’aria umida, si può ri¬

tenere che la variazione delle precipitazioni con la

quota non sia significativa. Pertanto è lecito riferire

1 3° C

1300 m m

GFMAMGLASOND

Fig. 1 - Climogramma secondo Bagnouls-Gaussen basato sui dati

termopluviometrici della stazione di Olginate (1981-1991).

tutti i valori di continentalità igrica (indice di Gams)

al totale annuo di 1.300 mm; ne deriva che dalla sta¬

zione di Olginate alla vetta del Barro l’indice varia

tra 9° e 35°, in evidente accordo con le caratteristi¬

che oceaniche del clima.

Un punto degno di nota è l’inversione termica che

contrassegna i versanti del Monte Barro caratterizza¬

ti da una componente in esposizione meridionale: in¬

fatti, in media, sotto i 500 m di quota prevalgono for¬

mazioni a tendenza più microterma ( Carpinion , Tilio-

Acerion) di quelle sovrastanti ( Quercion pubescenti-

petraeae ); a sud la roverella giunge quasi in vetta (850

m) dimostrando gli effetti microclimatici determinan¬

ti della buona esposizione.

Aspetti generali della vegetazione

Nel corso di una pluriennale serie di ricerche, svol¬

te dal personale scientifico del Museo di Storia Natu¬

rale di Milano, e orientate prevalentemente allo stu¬

dio dell’entomofauna del Monte Barro, sono state

condotte osservazioni sulla vegetazione e sulla flora,

in particolare su quest’ultima, a seguito dell’incom-

pletezza degli studi precedenti. Il campionamento en¬

tomologico è stato effettuato inizialmente su 20 sta¬

zioni, nove delle quali (Fig. 2) sono state successiva¬

mente studiate in modo più approfondito. Su otto di

queste ultime (versanti del Monte Barro, tra le quote

di 275 e 630 s.l.m.) è stato effettuato il rilevamento

floristico, di proposito limitato all’analisi dei prati di

versante.

Da un punto di vista fitoaltitudinale e vegetazio-

nale il Monte Barro si sviluppa tra le fasce medioeu¬

ropea e subatlantica della regione medioeuropea (Pi¬

gnatta 1979), afferenti ai seguenti climax forestali po¬

tenziali: Carpinion betuli Issi. 31 em. Oberd. 57, Tilio

platyphylli-Acerion pseudoplatani Klika 55 e Quer¬

cion pubescenti-petraeae Br.-Bl. 32 em. Rivas-Marti-

nez 72. La realtà attuale presenta una situazione di

notevole dinamismo vegetazionale, con esclusione

delle aree rocciose, dove non esiste potenzialità fore¬

stale e il climax di base corrisponde alle formazioni

casmofitiche dell’ordine Potentilletalia caulescenti

Br.-Bl. in Br.-Bl. & Jenny 26. La parte sommitale del

ASPETTI FLORISTICO - VEGETAZIONALI DEL MONTE BARRO (PREALPI DI LECCO)

141

Fig. 2 - L’area campionata del Parco del Monte Barro. Sono indi¬

cati i numeri corrispondenti alle stazioni 1-9.

monte Barro, in corrispondenza del principale affio¬

ramento roccioso, concentra l’endemismo sudalpico,

sudestalpico e insubrico. Ne sono esempi Physoplexis

comosa, Telekia speciosissima, Campanula raineri ,

Viola dubyana, Primula auricula ecc. In numerose sta¬

zioni, per esempio a Pian Sciresa, la glacializzazione è

stata totale e qui come altrove oggi si osserva un for¬

te scollamento tra rizosfera e substrato pedogenetico,

nel senso che la base calcarea smette precocemente di

influenzare l’evoluzione del suolo a causa dell’inten¬

so dilavamento, favorito anche dalle pendenze, un fe¬

nomeno comune e diffuso in tutta l’area insubrica.

Qui la potenzialità vegetazionale è rappresentata da

una brughiera riconducibile a formazioni dell’allean¬

za Genistion Bòchh. 43, che vedono la partecipazione

di Calluna vulgaris , Genista germanica , Molinia cae-

rulea subsp. arundinacea , Potentilla erecta, Stachys of¬

ficinali e Serratula tinctoria. L’elemento arboreo in

questo caso è rappresentato dal tremolo ( Populus tre¬

mula) e dalla betulla ( Betula penduta), molto fre¬

quenti in tutto il settore nordorientale del parco, la

cui diffusione però sembra legata significativamente

alla distribuzione degli incendi; questa pratica d’altra

parte favorisce selettivamente la stessa brughiera.

La vegetazione attuale nell’ambito delle potenzia¬

lità forestali è il risultato di una fase generalizzata di

abbandono e sospensione dell’attività umana sul suo¬

lo, al termine di una lunga storia di alterne vicende di

contrazione ed espansione del bosco, determinate di

volta in volta dai diversi momenti storico-economici.

I versanti esposti a sud e a ovest, potenzialmente ri¬

coperti di querceto termofilo a roverella, si caratte¬

rizzano oggi per una diffusione più o meno larga del¬

le praterie a Bromopsis erecta (incl. B. condensata) e

Brachypodium rupestre subsp. caespitosum. Queste

possono essere riferite all’ordine Brometalia erecti

Br.-Bl. 36 e a un'alleanza con carattere intermedio

tra Mesobromion erecti Br.-Bl. & Moor 38 e Diplach-

nion (Kengion) Br.-Bl. 61, secondo il punto di vista di

Royer (1991) che considera quest'ultimo syntaxon di

posizione incerta tra i Brometalia e i Festucetalia va-

lesiacae Br.-Bl. & Tx. 43. Gli aspetti più xerotermofi-

li di dette praterie, particolarmente diffusi in corri¬

spondenza degli affioramenti calcarei in buona espo¬

sizione, appartengono all’alleanza Xerobromion (Br.-

Bl. & Moor 38) Moravec in Holub et al. 67; questo ti¬

po di vegetazione non è stato preso in considerazio¬

ne nel presente lavoro. Le praterie in generale deno¬

tano diversi gradi di inarbustamento in relazione alla

tendenza autorigenerativa del bosco ora in atto. Spe¬

cialmente i versanti orientali e settentrionali com¬

prendono superfici a prato che ancora vengono in

qualche modo gestite e che dal punto di vista fitoso-

ciologico corrispondono in media all’associazione

Centaureo dubiae (nigrescentis)-Arrhenatheretum

elabori Oberd. 64. (Galasso 1994, ined.) Sia ai limiti

del prato sia nel contesto delle praterie termofile, co¬

me pure nelle aperture del bosco, sono diffusissimi gli

elementi di mantello, cioè associazioni del Geranion

sanguinei Tx. 61 caratterizzate da elevate frequenze e

coperture di Geranium sanguineum, Origanum vul-

gare, Vincetoxicum hirundinaria, Knautia drymeia

subsp. centrifrons , Teucrium chamaedrys e Thymus

pulegioides. La presenza di Viola hirta, Potentilla alba

e Trifolium medium è facilitata dai processi locali di

acidificazione del suolo e contrassegna una tipologia

associazionale ascrivibile all’alleanza Trifolion medii

Th. Muller 61. Infine merita un cenno la stazione di

Ca’ di Sala (Stazione 9 delle raccolte entomologiche),

sulla riva settentrionale del bacino di Oggiono (lago

di Annone), presa in considerazione nella ricerca en¬

tomologica come appendice del territorio del Monte

Barro con caratteristiche ecologiche particolari. Qui

la vegetazione non presenta regolare successione di

cinture lungo un gradiente idrico a causa delle modi¬

ficazioni geomorfologiche indotte dall’uomo; sono ri-

conoscibili tre aspetti essenziali: 1) il canneto ( Phrag -

mitetum australi Schmale 39) con accenni di aggrup¬

pamento a Iris pseudacorus , elementi di magnocari-

ceto ( Caricetum elatae W. Koch 26) e residui di bo¬

scaglia ripariale ( Salicion cinereae Muli. & Gòrs 58,

Alno-Ulmion Br.-Bl. & Tx. 43); 2) il prato umido oli¬

gotrofico ( Molinion caeruleae W. Koch 26); 3) vegeta¬

zione erbacea perenne e disorganizzata, al margine

superiore della stazione, riconducibile alle classi Ar¬

temisietea vulgaris Lohm., Prsg. & Tx. in Tx. 50 (sot¬

toclasse Artemisienea vulgaris Th. Muli. 81 in Oberd.

83) e Plantaginetea majoris Tx. 50 em. Oberd. et al. 67.

Benché necessaria, non è scopo della presente ri¬

cerca una verifica critica, in termini di moderne con¬

cezioni sistematiche e tassonomiche, della flora e del¬

la vegetazione del Monte Barro; per quanto sinora

pubblicato si rinvia a Fornaciari (1994) e Cerabolini

& Villa in Fornaciari (1994). Tuttavia lo studio bota¬

nico delle stazioni di rilevamento entomologico ha

messo in evidenza aspetti, specialmente della flora,

che inducono a prendere seriamente in considerazio¬

ne il problema di una revisione globale, date le pre¬

messe numeriche (oltre un migliaio di specie secondo

Fornaciari (1994)) e la particolare ricchezza di am¬

bienti, per un’analisi delle biodiversità alfa e beta,

davvero notevoli e ancora tutte da quantificare.

142

ENRICO BANFI, GABRIELE GALASSO & DAVIDE SASSI

La flora delle stazioni rilevate: novità e precisazioni

Viene riportato qui di seguito, accompagnato da

brevi note, l’elenco sistematico della flora delle otto

stazioni oggetto del presente studio, precisando che il

modello di ordinamento seguito, riguardo ai taxa di

rango superiore al genere, è quello di Cronquist

(1988) per quanto attiene le dicotiledoni e di Dahl-

gren (1989) per le monocotiledoni. Per semplicità i

generi e le specie sono ordinati alfabeticamente al¬

l’interno delle famiglie. La nomenclatura binomia se¬

gue in linea di massima Pignatti (1982), tranne nei ca¬

si di aggiornamenti successivi derivati da specifici la¬

vori di revisione sistematico-tassonomica e nomen-

claturale, parte dei quali è riportata in Greuter et al.

(1984-1991) e parte sarà citata all’occorrenza; in caso

di discordanza nomenclaturale, il binomio usato in

Flora d’Italia è riportato come sinonimo.

Pinaceae

Pinus sylvestris L. subsp. sylvestris

Introdotta a scopo forestale, questa specie non

sembra far parte del contesto vegetazionale attuale,

almeno in termini climatici (isoepira alla vetta: 35°).

Aristolochiaceae

Aristolochia pallida Willd.

Ranunculaceae

Clematis recta L.

Helleborus niger L. subsp. niger

Ranunculus acris L.

Ranunculus bulbosus L.

Thalictrum minus L.

Fagaceae

Quercus pubescens Willd.

Betulaceae

Corylus avellana L.

Ostrya carpinifolia Scop.

Caryophyllaceae

Cerastium fontanum Baumg. subsp. vulgare

(Hartm.) Greuter & Burdet

(= C. holosteoides Fr. subsp. triviale (Spenn.) Mò¬

schi, non (Link) Mòschi).

Petrorhagia saxifraga (L.) Link subsp. saxifraga

Silene pratensis (Rafn) Godr.

(= S. alba (Mill.) Krause subsp. alba).

Per la nomenclatura si veda Aeschimann & Bur¬

det (1994).

Silene vulgaris (Moench) Garcke subsp. vulgaris

Polygonaceae

Rumex acetosa L.

Rumex acetosella L.

Clusiaceae

Hypericum perforatum L. subsp. perforatum

Malvaceae

Malva alcea L.

La var. fastigiata (Cav.) Fiori, indicata da Forna-

ciari (1994) per questi popolamenti, non ha alcuna

base sistematica rappresentando una delle tante com¬

binazioni di stati di carattere (pelosità e incisioni del¬

la lamina) di natura tipicamente popolazionale, sog¬

getta cioè a flusso genico continuo.

Cistaceae

Helianthemum nummularium (L.) Mill.

Fornaciari (1994) ritiene che i popolamenti in og¬

getto vadano attribuiti al tipo nominale della specie

(subsp. nummularium ), tuttavia, se il carattere riguar¬

dante la pagina inferiore della foglia (verde pallido,

non bianco-grigiastro) è effettivamente in armonia

con la descrizione originale del taxon, e ammesso che

quest’ultimo sia consistente sul piano sistematico,

l’entità in oggetto andrebbe riferita piuttosto alla

subsp. obscurum (Celak.) Holub, che fra l’altro, se¬

condo Pignatti (1982), sarebbe particolarmente fre¬

quente al piede delle Alpi. In ogni caso, sulla variabi¬

lità infraspecifica di H. nummularium vige ancora

gran confusione, come si deduce dalla diversità delle

trattazioni (cfr., per esempio, Flora d’Italia, Flora Eu-

ropaea e Flora Iberica); sarà quindi opportuno, in at¬

tesa di una soddisfacente revisione, attenersi indicati¬

vamente al rango di specie.

Salicaceae

Populus tremula L.

Brassicaceae

Arabis collina Ten.

Biscutella laevigata L. subsp. laevigata

Fornaciari (1994) identifica il popolamento bar-

rense con la var. glabra Gaudin, della quale riconosce

tre forme per altro assolutamente prive di valore, al¬

meno finché non si disponga di un’adeguata interpre¬

tazione del modello di variabilità di questa specie.

Turritis glabra L.

(= Arabis glabra (L.) Bernh.).

Ericaceae

Calluna vulgaris (L.) Hull

Rosaceae

Amelanchier ovalis Medik. subsp. ovalis

Cotoneaster nebrodensis (Guss.) Koch

Potentilla alba L.

Assieme a Trifolium medium e Viola hirta caratte¬

rizza la versione acidoclina della vegetazione di man¬

tello, attribuibile all’alleanza Trifolion medii Th. Mul-

ler 61.

Potentilla recta L.

Fornaciari (1994) ne identifica la var. obscura (Ne-

stl.) Koch nei «prati aridi a Coera», ma gli esemplari

da noi rilevati nel prato sopra al Monumento dell’Al¬

pino (rii. 3) presentano costantemente petali giallo

sbiadito e corrispondono dunque al tipo nominale

(var. recta). La convivenza territoriale delle due for¬

me cromatiche fa ritenere che esse non abbiano alcu¬

na consistenza sistematico-tassonomica, tanto più che

sembrerebbero fondate sull’incapacità di un solo al¬

ide di codificare per uno dei pigmenti vacuolari dei

petali.

Prunus avium L.

Sanguisorba minor Scop. subsp. minor

Sorbus aria (L.) Crantz

Fabaceae

Anthyllis vulneraria L. subsp. weldeniana (Rchb.)

Cullen provv.

(= A. v. subsp. polyphylla sensu Fornaciari et sub-

ASPETTI FLORISTICO - VEGETAZIONALI DEL MONTE BARRO (PREALPI DI LECCO)

143

sp. praepropera sensu Fornaciari, A. x adriatica Beck

sensu Pignatti).

La tassonomia di questo difficile pool di variazio¬

ne infraspecifica (gruppo rimarci di Pignatti (1982)) è

completamente in alto mare per la mancanza di un

convincente riferimento sistematico. In altra occasio¬

ne (Banfi, 1983) si ritenne di attribuire l’entità in og¬

getto al presunto notomorfo A. x adriatica Beck sen¬

su Pignatti, epiteto comunque inadeguato perché ol¬

tre tutto di rango specifico, al quale sembrava meglio

corrispondere la combinazione dei caratteri in uso

osservati. Tuttavia sia il numero di segmenti delle fo¬

glie inferiori, sia la pelosità del calice, sia il pattern

della pigmentazione (giallo e rosso variamente distri¬

buiti su corolla e calice), si mostrano incostanti e im¬

prevedibili fra segmenti contigui di popolazione. For¬

naciari (1994) in questi popolamenti identifica senza

ombra di dubbio le sottospecie polyphylla (DC.) Ny-

man e praepropera (A. Kern.) Bornm. (per non par¬

lare delle «indispensabili» precisazioni sulle forme),

assunto inaccettabile perché scientificamente privo

di verifica. L’adozione da parte nostra del trinomio

A. vulneraria subsp. weldeniana , in sintonia con Greu-

ter et al. (1991), intende unicamente e provvisoria¬

mente riportare sotto questa combinazione, comun¬

que formalmente prioritaria rispetto ad A. x adriati¬

ca , tutta la variazione di tipo maura osservata nel ter¬

ritorio. Ciò in attesa di futuri chiarimenti sistematici e

nomenclaturali.

Chamaecytisus hirsutus (L.) Link subsp. hirsutus

La revisione di Cristofolini (1991) relativa a Cyti-

sus sect. Tubocytisus ha indubbiamente portato nuo¬

va luce sulle affinità all’interno del gruppo. Tuttavia

non ci sentiamo di condividere un’inclusione tout-

court di Chamaecytisus Link in Cytisus, poiché nel

complesso riteniamo continuino a sussistere chiari

elementi morfosistematici di base, di notevole valore

operativo, che rendono comunque Chamaecytisus

una realtà congruente a livello di genere. Anche la re¬

cente monografia di Pajero et al. (1994) continua a

mantenere separati i generi in questione.

Cytisophyllum sessilifolium (L.) O. Lang

(= Cytisus sessilifolius L.).

Nomenclatura secondo Greuter et al. (1991).

Cytisus emeriflorus Rchb.

Interessante endemita sudestalpico (non «insubri-

co» come altrove indicato, ma a corocentro insubri-

co) con una disgiunzione nelle Prealpi Friulane.

Cytisus scoparius (L.) Link

Genista germanica L.

Genista tinctoria L. subsp. tinctoria

L'indicazione di Fornaciari (1994) della subsp.

ovata (Waldst. & Kit.) Arcang. per i boschi tra l’Ere¬

mo e Pian Sciresa lascia notevoli perplessità in base a

quanto sinora noto sulla corologia (Pignatti, 1982),

ma soprattutto per la mancanza di studi moderni sul¬

la variabilità infraspecifica. Certo, come esemplari di

ambiente boschivo, è lecito sospettare trattarsi di

semplice ecomorfosi.

Hippocrepis coni osa L.

Lathyrus pratensis L.

Lotus comiculatus L.

Medicago lupulina L.

Ononis spinosa L. subsp. spinosa

Trifolium campestre Schreb.

Trifolium medium L.

Per l’ecologia si veda quanto detto a proposito di

Potentilla alba.

Trifolium montanum subsp. montanina

Trifolium pratense L. subsp. pratense

Trifolium repens L. subsp. repens

Vici a dumetorum L.

Entità nuova per la flora del Monte Barro. È sta¬

ta da noi raccolta lungo il margine boschivo del pra¬

to a nord del Monumento dell'Alpino (rii. 3). Galas¬

so (1989/90, ined.) ne ha confermato di recente la

presenza anche nel Triangolo Lariano (MSNM).

Vicia sativa L. subsp. nigra (L.) Ehrh.

(= V. s. subsp. angustifolia (Grufberg) Gaudin , V

s. subsp. segetalis (Thuill.) Gaudin).

Nomenclatura secondo Greuter et al. (1991).

Vicia sepium L.

Vicia villosa Roth subsp. villosa

Santalaceae

Thesium bavarum Schrank

Euphorbiaceae

Euphorbia cyparissias L.

Frequenti clorosi, deformazioni e sterilità indotte

da Uromyces pisi (Pers.) de Bary.

Euphorbia flavicoma DC. subsp. verrucosa (Fiori)

Pignatti

Rhamnaceae

Rhamnus saxatilis Jacq.

Polygalaceae

Polygala vulgaris L.

Geraniaceae

Geranium nodosum L.

Geranium sanguineum L.

Apiaceae

Astrantia major L. subsp. major

Cervaria rivinii Gaertn.

(= Peucedanum cervaria (L.) Lapeyr.).

Sistematica e nomenclatura secondo Pimenov &

Leonov (1993).

Daucus carota L. subsp. carota

Heracleum sphondylium L. subsp. sphondylium

Oreoselinum nigrum Delarbre

(= Peucedanum oreoselinum Moench).

Sistematica e nomenclatura secondo Pimenov &

Leonov (1993).

Pimpinella major (L.) Huds.

Trinia glauca (L.) Dumort.

Asclepiadaceae

Vincetoxicum hirundinaria Medik.

Convolvulaceae

Convolvulus arvensis L.

Boraginaceae

Echium vulgare L.

Lamiaceae

Clinopodium vulgare L.

Origanum vulgare L.

Prunella grandiflora (L.) Schòller

Salvia pratensis L.

Stachys alopecuros (L.) Benth. subsp. alopecuros

Stachys officinalis (L.) Trevis. subsp. officinalis

Stachys recta L. subsp. recta

144

ENRICO BANFI, GABRIELE GALASSO & DAVIDE SASSI

Teucrium chamaedrys L.

Teucrium montanum L.

Thymus pulegioides L.

Plantaginaceae

Plantago lanceolata L.

Plantago major L. subsp. major

Oleaceae

Fraxinus ornus L.

Scrophulariaceae

Melampyrum cristatum L.

Rhinanihus alectorolophus (Scop.) Pollich

Verbascum thapsus L. subsp. thapsus

Stranamente questa specie è passata inosservata

nel territorio del Monte Barro. Convive con la con¬

genere V. lychnitis L. non riportata nel presente elen¬

co in quanto estranea ai rilievi, nel prato a nord del

Monumento dell’Alpino (rii. 3), dove si presume sia

comparsa sinantropicamente.

Veronica arvensis L.

Veronica chamaedrys L.

Globulariaceae

Globularia cordifolia L.

Globularia nudicaulis L.

Campanulaceae

Phyteuma scheuchzeri All. subsp. columnae (Gau-

din) Bech.

Phyteuma spicatum L. subsp. spicatum

Rubiaceae

Cruciata glabra (L.) Ehrend.

Galium album Mill.

Galium lucidum All.

Galium mollugo L.

Galium rubrum L.

Galium veruni L. subsp. verum

Adoxaceae

Viburnum lantana L.

Riguardo all’attribuzione di Sambucus e Vibur¬

num alle Adoxaceae, qui adottata dagli scriventi, si

veda Zomlefer (1994). I due generi, diversamente,

possono essere considerati tipi di famiglie distinte

(Sambucaceae, Viburnaceae), in ogni caso senza rela¬

zioni con le Caprifoliaceae (Bolli, 1994).

Valerianaceae

Valeriana collina Wallr.

Dipsacaceae

Knautia arvensis (L.) Coult.

Knautia drymeia Heuff. subsp. centrifrons (Borbàs)

Ehrend.

Knautia transalpina (H. Christ) Briq.

Knautia velutina Briq.

Asteraceae

Achillea collina Becker

La specie non compare nell’elenco floristico del

Barro (Fornaciari, 1994). È entità subsinantropica,

che predilige i siti marginali asciutti e ben esposti.

Achillea roseoalba Ehrend.

Anche questa entità non è riportata da Fornaciari

(1994); probabilmente l’autore la identifica colletti¬

vamente con la precedente come A. millefolium L. Si

tratta di specie propria dei prati mesofili, caratteriz¬

zante il centaureo-arrenatereto.

Bellis perennis L.

Buphthalmum salicifolium L. subsp. salicifolium

La vai. grandi florum (L.) Fiori riportata da Forna¬

ciari (1994) senza citazione del revisore è un’entità da

interpretarsi, secondo Bechi & Garbari (1994), come

parte di un «commiscuum» (Danser, 1929), cioè un

insieme di individui interfecondi costituito da biotipi

geografici eteromorfi (facies regionali) formatisi per

selezione differenziale. Uno di questi biotipi è ap¬

punto la varietà in oggetto, che caratterizza la parte

occidentale dell’areale della specie (dalle Alpi Marit¬

time alle Retiche).

Centaurea grinensis Reut. subsp. grinensis

Secondo Dostàl (1976) questa entità è meritevole

di rango specifico, tanto più comportando essa una

vicariante geografica (subsp. fritschii (Hayek) Do¬

stàl), propria dei rilievi dell’Est europeo, che raggiun¬

ge le Alpi di striscio (Triestino, Friuli, Carnia (Pignat-

ti, 1982)). Rispetto a C. scabiosa L., con cui convive

nel territorio in studio, la nostra specie si distingue

per le appendici delle squame non o poco decorrenti,

con fimbrie brevi o assenti. Può considerarsi endemi¬

ca sudestalpica.

Centaurea nigrescens Willd.

Questa specie, comunissima nei prati falciati, stra¬

namente non compare nell’elenco di Fornaciari

(1994).

Centaurea rhaetica Moritzi

Fornaciari (1994) alla vetta, in esposizione orien¬

tale, riconferma la presenza della var. ensifolia (Rota)

Fiori (basionimo: C. austriaca Willd. var. ensifolia Ro¬

ta) già indicata dallo stesso Fiori (1927) per il Monte

Barro. Dal pool di variazione di C. rhaetica è stata re¬

centemente separata C. bugellensis Soldano (Solda-

no, 1996), endemica del Biellese e della Val Sesia e in

tale occasione lo stesso autore ha riesaminato anche

il taxon di Rota confermando l’opportunità di man¬

tenerne almeno per ora il rango varietale.

Centaurea triumfettii All. subsp. triumfettii

Le due forme riportate da Fornaciari (1994), cita¬

te tra l’altro senza revisore, sono del tutto inconsi¬

stenti.

Erigeron annuus (L.) Pers.

Hieracium umbellatum L.

Inula hirta L.

Che cosa intende Fornaciari (1994) con «f. poli-

cephala» (sic!)?

Leontodon hispidus L. subsp. hispidus

Leucanthemum vulgare Lam.

Scorzonera austriaca Willd.

Serratula tinctoria L. subsp. tìnctoria

Pignatti (1982) riporta due varietà, secondo For¬

naciari (1994) entrambe presenti nel territorio del

Barro. Tuttavia essendo grandissima e ancora quasi

del tutto inesplorata la variabilità infraspecifica, co¬

me già facevano notare Cannon & Marshall (1976),

preferiamo astenerci dal prendere posizione oltre la

sottospecie.

Tanacetum corymbosum (L.) Sch. Bip. subsp. corym-

bosum

Taraxacum sp. aggr. officinale

Non siamo in grado di fornire precisazioni sull’i¬

dentità di questo taxon, problema che richiederebbe

un esame approfondito sulla variabilità di «T. offici¬

nale Weber» nell’intero territorio prealpino.

Tragopogon pratensis L. subsp. pratensis

I

li

■

a

!

i

ASPETTI FLORISTICO - VEGETAZIONALI DEL MONTE BARRO (PREALPI DI LECCO)

145

Convallariaceae

Polygonatum odoratum (Mill.) Druce

La «f. angustifolia» (sic!) proposta da Fornaciari

(1994) per una «forma nemorosa a foglie strette» è

priva di valore tanto sul piano formale (nomen nu-

dum) come su quello della sostanza (variazione indi¬

viduale occasionale).

Hyacinthaceae

Omithogalum pyrenaicum L.

Liliaceae

Lilium bulbiferum L. subsp. croceum (Chaix) Baker

Orchidaceae

Gymnadenia conopsea (L.) R. Br.

Ophrys sphegodes Mill. subsp. sphegodes

(non «sphecodes» come in Fornaciari (1994)).

Cyperaceae

Carex austroalpina Bech.

Poaceae

Anthoxanthum odoratum L.

Arrhenatherum elatius (L.) P. Beauv.

Brachypodium rupestre (Host) Roem. & Schult. sub¬

sp. caespitosum (Host) H. Scholz

Nonostante la revisione di Lucchese (1987) per le

specie italiane e quella più recente di Schippmann

(1991) per il genere Brachypodium in Europa, alle

quali si rimanda per i dettagli, nei prospetti floristici

si continua a leggere «B. pinnatum (L.) P. Beauv.» (tra

questi Fornaciari, 1994), quando le uniche stazioni

italiane di tale specie, finora note con certezza, sono

localizzate nei settori più continentali delle Alpi. Il

medesimo errore viene purtroppo ripreso in modo

acritico anche nei lavori vegetazionali (nella fattispe¬

cie si veda Cerabolini & Villa in Fornaciari, 1994).

Briza media L.

Bromopsis erecta (Huds.) Fourr.

(= Bromus erectus Huds.).

L’elevazione a genere di Bromus L. sect. Pnigma

Dumort. è in linea con il punto di vista -da noi condi¬

viso- di diversi autori, a partire da Tzvelev (1976) per

arrivare a Stace (1991). Il popolamento qui esamina¬

to presenta occasionalmente individui con i caratteri

di B. condensata (Hack.) Holub (guaine fogliari lano¬

se e pannocchia contratta), il cui significato sistemati¬

co, nel caso di un’esatta corrispondenza tipologica, è

tutto da discutere, come del resto è da discutere la

congruenza delle altre variazioni del gruppo (B. ste-

nophylla, B. transsilvanica ecc.), visto che oltre tutto

non si differenziano per nulla sul piano ecologico.

Dactylis glomerata L. subsp. glomerata

Festuca valesiaca Schleich.

La specie, abbastanza diffusa nei brometi della zo¬

na archeologica affacciati a sud, non è riportata da

Fornaciari (1994). Come del resto non sono riportate

altre entità dello stesso genere, piuttosto frequenti,

che non possiamo includere nel presente elenco in

quanto estranee ai rilievi, ma che riteniamo doveroso

segnalare per la flora del Monte Barro. F. strida Ho-

< st subsp. trachyphylla (Hack.) Patzke (= F. tra-

chyphylla (Hack.) Krajina, F. brevipila Tracey), già in¬

dicata da Àrdissone (1903) sub «F. duriuscula», si in¬

contra sui pendìi soleggiati a sudovest del Monumen¬

to dell’Alpino; F. rubra L. subsp. fallax (Thuill.) Ny-

man (= F. diffusa Dumort., F. heteromalla Pourr., F.

rubra L. subsp. megastachys Gaudin) è frequente in

diversi punti a monte della strada per S. Michele, in

direzione di Pian Sciresa.

Helictotrichon pubescens (Huds.) Pilger

(= Avenula pubescens (Huds.) Dumort.).

Entità nuova per la flora del Barro, in ogni caso

piuttosto comune negli arrenatereti e stranamente

passata inosservata.

Koeleria pyramidata (Lam.) Domin

Lolium perenne L.

Molinia caerulea L. subsp. arundinacea (Schrank)

K. Richter

(= M. arundinacea Schrank, M. c. subsp. a. (Sch¬

rank) «Paul»).

Fornaciari (1994) di questa entità riferisce «Zone

paludose...», indicazione che lascia molte perplessità

poiché non corrisponde all’ecologia del taxon. D’al¬

tra parte l’autore sembra ignorare la grande diffusio¬

ne di questa sottospecie sui versanti, specialmente

settentrionale e orientale (compresa la brughiera di

Pian Sciresa), in condizioni di umidità superficiale e

lisciviazione evidenti. È nostra opinione che tutte le

indicazioni relative a «M. coerulea» vadano invece ri¬

ferite a questo taxon.

Poa pratensis L.

Schedonorus pratensis (Huds.) P. Beauv. subsp. pra¬

tensis

(= Festuca pratensis Huds.).

L’adozione di un genere distinto in questo caso è

in accordo con quanto espresso da Kerguélen &

Plonka (1989) riguardo a Festuca s.l. e rappresenta la

soluzione opposta a quella che propone Darbyshire

(1993) - secondo noi assurdamente riduttiva - di tra¬

sferire al genere Lolium tutte le entità di Festuca sub-

gen. Schedonorus.

S. arundinaceus (Schreb.) Dumort. subsp. arundi-

naceus (= Festuca arundinacea Schreb.) viene qui se¬

gnalata, anche se non compresa nei rilievi, in quanto

comune e diffusa specialmente nel piano basale e, an¬

cora una volta, inspiegabilmente non riportata nella

Flora di Fornaciari (1994).

Sesleria caerulea (L.) Ardoino

(= S. albicans Kit., S. varia (Jacq.) Wettst., nom. su-

perfl.).

Trisetaria flavescens (L.) Baumg. subsp. flavescens

(= Trisetum flavescens (L.) P. Beauv.).

La specie non è molto comune e si concentra più

che altro nei prati eutrofici. Per la tassonomia e la no¬

menclatura si veda Banfi & Soldano (1996).

Brevi considerazioni sulla vegetazione

dell’area rilevata

I rilievi fitosociologici effettuati in corrispondenza

delle stazioni di raccolta entomologica corrispondo¬

no a fasi aperte della vegetazione e, salvo il quinto

(Pian Sciresa), appartengono tutti a potenzialità fore¬

stale. Agli effetti delle interrelazioni floro-faunistiche

sembra utile un breve riepilogo degli elementi salien¬

ti. Nella tabella 1 per ogni rilievo vengono riportate

1) le specie con presenza >1, cioè non esclusive, che

ricoprano più del 5% della superficie, 2) le specie con

una sola presenza che caratterizzano in modo esclusi¬

vo la stazione. La tabella 1 non è ordinata fitosocio-

logicamente, ma alfabeticamente per taxa, e i valori

sono quelli di abbondanza-dominanza della scala di

Braun-Blanquet trasformati secondo van der Maarel

!

146

ENRICO BANFI, GABRIELE GALASSO & DAVIDE SASSI

(tabella di calcolo). Sebbene non evidenziati in appo¬

sito quadro d’associazione, si può arguire che i syn-

taxa meglio rappresentati sono: Arrhenatheretalia e

Arrhenatherion , Brometalia e Mesobromion/Diplach-

nion, Origanetalia , Quercetalia pubescenti-petraeae,

Fagetalia e Carpinion , e inoltre un manipoletto di

specie pertinenti al Genistion che isolano il rilievo 5

(Pian Sciresa) dal contesto generale.

Tab. 1 - Elenco alfabetico delle specie con i valori di

copertura secondo van der Maarel.

ASPETTI FLORISTICO - VEGETAZIONALI DEL MONTE BARRO (PREALPI DI LECCO)

147

Agli effetti delle relazioni tra entomofauna e ve¬

getazione ci è sembrato interessante fornire qualche

dato di carattere preliminare sulla fitodiversità ceno-

tica in termini di a-diversità. In base a precedenti

esperienze (Ferrari & Galanti 1972, Ferrari & Gran¬

di 1974. Banfi 1979, Anzaldi & al. 1988, Pignatti & al.

1991), abbiamo preferito l’indice di Shannon-Weaver

(log base 2) per un confronto delle stazioni rilevate.

Tuttavia, come osservano Lambshead et al. (1983), il

corretto impiego del parametro richiede una verifica

delle curve di k-dominanza (Fig. 3): se queste si inter¬

secano attorno alla metà del loro tragitto il confron¬

to degli indici di diversità non può considerarsi atten¬

dibile. Nella tabella 2 vengono riassunti i confronti

possibili, indicati con simbolo +.

Per ogni riga e per ogni colonna i quattro numeri

riportati corrispondono rispettivamenrte al numero

della stazione di campionamento, al numero delle

specie presenti, all'indice di Shannon e alla evenness.

Come si può osservare, la stazione del rilievo 6

(pendio a monte del sentiero che dall’ex-sanatorio

conduce alla vetta), benché più aperta delle altre (co¬

pertura dell’85%), floristicamente è la più diversifi¬

cata, presentando i massimi di specie e di evenness,

mentre il rilievo 4 (S. Michele, presso il sentiero per

Pian Sciresa), al quartultimo posto come numero di

specie, risulta il meno «disordinato» a causa delle

preponderanti coperture di Arabis collina, Arrhe-

natherum elatius, Helictotrichon pubescens e Triseta-

ria flavescens. L’analisi delle componenti principali

(PCA) mostra che le prime due componenti della va¬

riazione (Fig. 4) si identificano con il grado di ter-

moxerofilia (asse 1) manifestato dai Brometalia, e il

grado di ripresa vegetazionale o stato di abbandono

(asse 2) evidenziato da Origanetalia e Prunetalia. I

rapporti gerarchici di somiglianza fra le stazioni sono

visibili nel dendrogramma di Fig. 5, che è stato calco¬

lato (UPGMA) sulla matrice dei coefficienti di simi¬

litudine percentuale. Le stazioni 1 e 3 corrispondono

al prato mesofilo insubrico classico ( Centaureo nigre-

scentis-Arrhenather etum), come pure le stazioni 2 e 4,

che tuttavia risentono di abbandono per la maggiore

Fig. 3 - Curve di k-dominanza relative alle stazioni 1-8.

148

ENRICO BANFI. GABRIELE GALASSO & DAVIDE SASSI

Tab. 2 - Confronto dei rilievi sulla base delle curve di

k-dominanza. I quattro numeri delle caselle marginali

indicano, dall’alto in basso: il numero di rilievo, il tota¬

le della specie, l’indice di diversità di Shannon e le

evenness. Il simbolo + indica i confronti possibili.

residua, testimoniata anche dalla non significatività

del mantello.

Dominanze: Lolium perenne, Dactylis glomerata,

Centaurea nigrescens, Trisetaria flavescens, Knautia

velutina, Trifolium repens. Specificità: Lolium peren¬

ne, Cerastium fontanum vulgare.

Stazione 2: Località Piani di Barra, 600 m, esp. W,

dal 1990 interessata da scavi archeologici in rapporto

al cosiddetto Edificio II. Leggera prevalenza di pra¬

teria e mantello su prato falciabile, cioè netta risposta

all’abbandono di una gestione a foraggio già indebo¬

lita.

Dominanze: Galium verum, Geranium sangui-

neum, Arrhenatherum elatius, Festuca valesiaca, Leon-

todon hispidus, Helictotrichon pubescens. Specificità:

Valeriana collina, Vicia sepium.

Stazione 3: Conca prativa a monte del Monumen¬

to all’Alpino, 630 m, esp. W. Convivenza di elementi

di prateria, elementi di prato falciabile ed elementi di

disturbo marginale.

Dominanze: Bromopsis erecta, Arrhenatherum

elatius, Centaurea nigrescens, Salvia pratensis, Triseta¬

ria flavescens. Specificità: Erigeron annuus, Potentilla

recta, Convolvulus arversis, Turritis glabra, Verbascum

thapsus, Schedonorus pratensis, Vicia dumetorum.

Stazione 4: Località S. Michele, pendio in prossi¬

mità del sentiero per Pian Sciresa, 325 m, esp. E. Su

una base di Mesobromion erecti ( Thalictrum minus,

Arabis collina ) è in pieno sviluppo il prato falciabile,

che qui presenta il carattere oligo-mesotrofico.

Staz 5 ♦ o.6

♦ Staz 8

0.2

♦ Staz. 6

ON

o

« 1 - ►—

(0 ■°'3 -0,2

-0.2

• Sfaz 7

0,3

♦ Staz. 2

• Staz 4

0.4 05 0.6

♦ Staz. 3

-0,4

-0.6

♦ Staz 1

asse 1

Fig. 4 - Confronto delle stazioni 1-8 mediante analisi delle com¬

ponenti principali.

diffusione di elementi del Geranion sanguinei/Trifo-

lion medii. In posizione intermedia, sotto quest’ulti¬

mo aspetto, si collocano le stazioni 7 e 8, che presen¬

tano in più una tendenza termoxerofila ( Mesobro -

mion/Diplachniorì)\ infine le stazioni 5 e 6, pure in ab¬

bandono, identificano l’aspetto più termoxerofilo

dell’area campionata con una preponderante presen¬

za di elementi di Brometalia, Mesobromion e Dipla-

chnion.

Caratteri specifici delle stazioni rilevate

Stazione 1: Località Piani di Barra, 610 m, esp. W,

dal 1990 interessata da scavi archeologici in rapporto

al cosiddetto Grande Edificio. Consistente presenza

di prato falciabile che indica una attività di foraggio

0,3

6 5 8 7 4 2 3 1

Fig. 5 - Dendrogramma delle stazioni 1-8 (WPGMA su Percent

Similarity).

I

ASPETTI FLORISTICO - VEGETAZIONALI DEL MONTE BARRO (PREALPI DI LECCO)

149

Dominanze: Arrhencitherum elatius, Thalictrum

minus, Silene vulgaris, Trisetaria flavescens, Rhi-

nanthus alectorolophus, Arabis collina, Helictotrichon

pubescens. Specificità: Petrorhagia saxifraga.

Stazione 5: Località Pian Sciresa, 435 m, esp. NE.

Prato arido con montarozzi residuali a brughiera. Si

caratterizza meglio di tutte le altre stazioni per la pre¬

senza delPelemento di brughiera, accompagnato da

Cytisus emeriflorus , endemismo calcicolo SE-alpico.

Per il resto il livello di base è costituito da prateria a

Brachypodium rupestre caespitosum.

Dominanze: Brachypodium rupestre caespitosum,

Calluna vulgaris, Molinia caerulea arundinacea, Po-

pulus tremula. Specificità: Calluna vulgaris, Cha-

maecytisus hirsutus, Cytisus emeriflorus, Cytisus sco-

parius, Genista germanica, Molinia caerulea arundi¬

nacea, Pinus sylvestris.

Stazione 6: Superfici prative lungo il sentiero del¬

la «Cresta occidentale», che dall’edificio dell’ex sana-

; torio sale alla vetta, 750 m, esp. S. Prateria con par¬

ziale affioramento roccioso, fortemente cespugliata e

in via di chiusura. Forte influsso dell’elemento prene-

morale, con tendenza a un Quescetum pubescenti s. 1.

L’elemento di mantello ha scarso peso.

Dominanze: nessuna. Specificità: Serratula tinctoria,

Sorbus aria, Cytisophyllum sessilifolium, Helleborus ni-

ger, Cotoneaster nebrodensis, Globularia nudicaulis,

Phyteuma scheuchzeri columnae, Centaurea rhaetica,

Euphorbia flavicoma verrucosa, Carex austroalpina,

Origanum vulgare, Gymnadenia conopsea, Amelan-

chier ovalis, Galium lucidum, Melampyrum cristatum.

Stazione 7: Località Fornaci Villa, in prossimità

dell'impluvio della Val Faè. Superficie prativa terraz¬

zata all’interno del bosco mesofilo, 275 m, esp. NW.

Molto simile a quella della stazione 8, ma più aperta

e con qualche elemento in più di Mesobromion.

Dominanze: Nessuna. Specificità: Ophrys sphego-

des, Vicia sativa nigra.

Stazione 8: Località Fornaci Villa, in prossimità

dell’impluvio della Val Faè. Superficie prativa terraz¬

zata all’interno del bosco mesofilo, 305 m, esp. NW.

Prato irregolarmente gestito e contornato da un bo¬

sco con notevoli contrassegni mesofili. Ciò è conse¬

guenza dell’esposizione fresca e di un maggiore svi¬

luppo di suolo. Sono comunque sempre presenti gli

elementi di prateria.

Dominanze: Brachypodium rupestre caespitosum,

Tanacetum corymbosum, Astrantia major. Specificità;

Astrantia major, Prunus avium, Geranium nodosum.

Stazione 9: Località Ca’ di Sala, 226 m, sulla riva

settentrionale del bacino di Oggiono del Lago di An¬

none. Questa stazione non è stata rilevata fitosocio-

logicamente, ma solo floristicamente. Vi si evidenzia¬

no tre aspetti essenziali: 1) il canneto ( Phragmitetum

australi ) con accenni di aggruppamento a Iris pseu-

doacorus , elementi di magnocariceto ( Caricetum ela-

taej e residui di boscaglia ripariate ( Salicion cine-

reae)\ 2) il prato umido oligotrofico ( Molinion caeru-

leae ); 3) vegetazione erbacea perenne e disorganizza¬

ta, al margine superiore della stazione, riconducibile

alte classi Artemisietea vulgaris e Plantaginetea majo-

ris.

150

ENRICO BANFI, GABRIELE GALASSO & DAVIDE SASSI

Fig. 6 - Facies marginale di prato mesofilo ( Centaureo nigrescentis-

Arrhenatheretum) con dominanza locale di Helictotrichon pube-

scens e Rhinanthus alectorolophus.

Fig. 7 - La brughiera di Pian Sciresa fisionomizzata da Collima vul-

garis e Molinia caerulea subsp. arundinacea.

Fig. 8 - Bromopsis erecta (incl. B. condensata ), elemento caratte¬

rizzante il prato meso-xerofilo ( Mesobromion ).

Fig. 9 - Anthyllis vulneraria subsp. weldeniana provv., componente

del Mesobromion , non è ancora risolta sul piano sistematico-tas-

sonomico e presenta variabilità intrapopolazionale anche nella

colorazione del calice e della corolla.

Fig. 10 - C otinus coggygria , differenziale calcicola e termofila del- Fig. 11 - Potentina recta var. recto nel prato sopra il monumento

l’ordine Quercetalia pubescenti-petraeae. dell’Alpino (staz. 3).

ASPETTI FLORISTICO - VEGETAZIONALI DEL MONTE BARRO (PREALPI DI LECCO)

151

Fig. 12 - Festuca valesiaca appartiene al contingente più continen¬

tale e caratterizza localmente il Mesobromion e lo Xerobromion.

Fig. 13 - Stipa eriocaulis subsp. eriocaulis caratterizza gli aspetti più

xerotermofili, riscontrabili in affioramento calcareo ( Xerobromion ).

Fig. 14 - Trinia glauca , componente di Xerobromion e differenzia¬

le edafica (calcare).

Fig. 15 - Thesium bavarum è entità legata essenzialmente ai quer¬

ceti di roverella su base calcarea.

Fig. 16 - Clinopodium volgare fa parte del manipolo di specie gui¬

da della vegetazione di mantello ( Origanetalia ).

Fig. 17 - Potentilla alba differenzia in senso acidofilo e oligotrofi¬

co la vegetazione di mantello ( Trifolion medii).

152

ENRICO BANFI, GABRIELE GALASSO & DAVIDE SASSI

BIBLIOGRAFIA

Aeschimann D. & Burdet H., 1994 - Flore de la Suisse. Le nou-

veau Binz. Editions du Griffon , Neuchàtel.

Anzaldi G, Mirri L„ Pignatti S. & Ubrizsy Savoia A., 1988 -

Synthetical data of chorotypes distribution of thè Italian flora.

Annali di Botanica , Roma, 46: 59-66.

Ardissone F., 1903 - Catalogo delle piante vascolari del Monte

Baro. Meni. Regio Ist. Lonib. Sci. Lett. Arti , ser. Ili cl. Sci. mat.

e nat.. Milano, 20/21:1-102.

Banfi E., 1979 - Alcuni rilievi di vegetazione del litorale massese

(Toscana settentrionale). Natura, Milano, 70 (IV): 229-241.

Banfi E., 1983 - Additamenta floristica longobarda. 2. Note su

Malvaceae, Fabaceae, Apiaceae, Campanulaceae, Poaceae. At¬

ti Soc. it. Sci. nat. Museo civ. Stor. nat. Milano, Milano, 124 (3-

4): 262-268.

Banfi E. & Soldano A., 1996 - Dati tassonomici e nomenclatura-

li su Poaceae dell'Europa e del Mediterraneo. Atti Soc. it. Sci.

nat. Museo civ. Stor. nat. Milano, Milano, 135 (2): 379-387.

Bechi N. & Garbari E, 1994 - Intraspecific variation and taxo-

nomic aspects of some plants from Apuan Alps (Tuscany,

Italy). Flora Mediterranea, Palermo, 4: 213-225.

Belloni S. & Pelfini M., 1987- Il gradiente termico in Lombardia

- Acqua Aria, mensile di scienze e tecniche ambientali. Milano,

1987 (4): 441-447.

Bolli R., 1994 - Revision of thè genus Sambucus. Dissert. bot.,

Berlin-Stuttgart, 223: 1-227, 29 tav.

Cannon J.F.M. & Marshall J.B., 1976 - Serranda L. inTutinT.G. et

al.: Flora Europaea, 4. Cambridge University Press, Cambridge.

Cerabolini B. & Villa M„ 1994 - La vegetazione del Monte Bar¬

ro. In: Fornaciari G.: Flora e vegetazione del Monte Barro.

Paolo Cattaneo Grafiche, Oggiono.

Cristofolini, 1991 - Taxonomic revision of Cytisus Desf. sect. Tu-

bocytisus DC. (Fabaceae). Webbia, Firenze, 45 (2): 187-219.

Cronquist A., 1988 - The evolution and classification of flowering

plants. The New York Botanical Garden, Bronx, New York.

Dahlgren G., 1989 - An updated angiosperm classification. Bot.

Journ. Finn. Soc., London, 100: 197-203.

Danser B.H., 1929 - Ùber die Begriffe Komparium, Kommi-

skuum und Konvivium und tìber die Entstehungsweise der

Konvivien. Genetica, Dordrecht, 11: 399-450.

Darbyshire S.J., 1993 - Realignment of Festuca subgenus Sche-

donorus with thè genus Lolium (Poaceae). Novon, Ottawa, 3:

239-243.

Dostàl J., 1976 - Centaurea L. In: Tutin T.G. et al.: Flora Euro¬

paea, 4. Cambridge University Press, Cambridge.

Ferrari C. & Galanti G., 1972 - Specie indicatrici e struttura

della vegetazione nei calanchi della valle del Santerno (Bolo¬

gna). Arch. bot. biog. it., Forlì, 48, serie 4, voi. 17(3-4): 131-145.

Ferrari C. & Grandi G., 1974 - La vegetazione dei calanchi nel¬

le argille plioceniche della valle del Santerno. Arch. bot. biog.

it., Forlì, 50, serie 4, voi. 20 (3-4): 3-16.

Fiori A., 1927 - Nuova flora analitica d’Italia. Tipografia del Se¬

minario, Padova, 2 (5).

Fornaciari G., 1994 - Flora e vegetazione del Monte Barro. Pao¬

lo Cattaneo Grafiche, Oggiono.

Galasso G., 1989/90 (ined.) - Aspetti geobotanici della Valle del¬

la Roncaglia e del Piano del Tivano (Triangolo Lariano). Tesi

di laurea, Fac. Scienze Mat. Fis. Nat., Università degli Studi di

Milano.

Galasso G., 1994 (ined.) - Inquadramento fitosociologico della

Cava di Vallescura e zone limitrofe (Galbiate (LC), Parco Re¬

gionale del Monte Barro) e determinazione delle linee dina¬

miche di evoluzione della vegetazione al fine di orientarne lo

sviluppo. Consulenza inedita, Milano.

Greuter W., Burdet H.M. & Long G., 1984-1991 - Med Check-

list (voi. 1, 3, 4). Conserv. et Jard. bot. Ville de Genève, Genève.

Kerguélen M. & Plonka E, 1989 - Les Festuca de la flore de

France. Soc. bot. Centre-Ouest, Dignac.

Lambshead P.J.D., Platt H.M. & Shaw K.M., 1983 - The detec¬

tion of differences among assemblages of marine benthic spe-

cies based on an assessment of dominance and diversity.

Journ. nat. History, London, 17: 859-874.

Lucchese E, 1987 - Ruolo di alcune specie del genere Brachypo-

dium nelle associazioni prative e forestali. Not. Fitosoc., Albe-

se, 23: 173-188.

Nangeroni G., 1972 - Il Monte Barro (Prealpi lombarde). Note di

geomorfologia. Natura, Milano, 63 (2): 159-196.

Pajero P., Martini F. & Colpi C., 1993 - Leguminose arboree e

arbustive in Italia. Ed. Lint, Trieste.

Pignatti S., 1979 - I piani di vegetazione in Italia. Giorn. bot. it.,

Firenze, 113:411-428.

Pignatti S., 1982 - Flora d’Italia. Edagricole, Bologna.

Pignatti E., Pignatti S„ Huang C.-C., Ding G.-Q. & Huang Z.-

L., 1991 - B-Diversity and phytogeographical patterns in thè

Ding Hu Shan Reserve (Guangdong - South China) forest ve-

getation. Rend. Fis. Acc. Lincei, Roma, serie 9, 2 (1): 79-85.

Pimenov M.G. & Leonov M.V., 1993 - The genera of thè Umbel-

liferae. A nomenclator. Royal bot. Gard., Kew.

Royer J.M., 1991 - Synthèse eurosibérienne, phytosociologique et

phytogéographique de la classe Festuco-Brometea. Diss. Bot.,

Berlin Stuttgart, 178: i-vi, 1-296.

Schippmann U., 1991 - Revision der europàischen Arten der Gat-

tung Brachypodium Palisot de Beauvois. Boissiera, Genève,

45: 1-249.

Soldano A., (1996) - Un rango specifico per la Centaurea ende¬

mica del Biellese-Val Sesia. Natura Bresciana, Brescia, 30.

Stace C.A., 1991 - New Flora of thè British Isles. Cambridge Uni¬

versity Press, Cambridge.

Tomaselli R„ Balduzzi A. & Filipello S., 1973 - Carta biocli¬

matica d’Italia. Collana Verde, Min. AA. FF., Roma, 33: 1-24.

Tzvelev N.N., 1976 - Zlaki SSSR (Grasses of thè Soviet Union).

Oxonian Press Pvt. Ltd., New Delhi-Calcutta.

Zomlefer W.B., 1994 - Guide to Flowering Plant Families. The

University of North Carolina Press, Chapel Hill.

Enrico Banfi: Museo Civico di Storia Naturale, Sezione Botanica, Corso Venezia 55, 20121 Milano

Gabriele Galasso: Via Palmi 18,20152 Milano

Davide Sassi: Via S. Rocco 17, 22030 Castelmarte CO

Studi geobotanici ed entomofaunistici nel Parco Regionale del Monte Barro

Memorie della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano

Volume XXVII - Fascicolo II - 1997

Carlo Leonardi

Ricerca entomofaunistica nel parco regionale

del Monte Barro (Italia, Lombardia, Lecco)

Riassunto - Si descrivono in modo sintetico i risultati di raccolte entomofaunistiche condotte nell’area del Monte Bar¬

ro (Lecco) negli anni 1989-1992 dal Museo Civico di Storia Naturale di Milano. La ricerca è stata prevalentemente orien¬

tata al censimento dell’entomofauna fitofaga di stazioni prative. Sono state identificate 714 entità sistematiche appartenen¬

ti a Eterotteri, Coleotteri, Imenotteri, Sinfiti e Ragni; 65 taxa sono risultati nuovi per la Lombardia e 5 nuovi per l'Italia.

Abstract - Entomofaunistic researches in thè regional park of Monte Barro (Italy, Lombardy, Lecco).

The results of a study carried out by thè Naturai History Museum of Milano in thè area of Monte Barro (Lecco) during

thè years 1989-1992 are synthetically reported. Phytophagous species of meadows have been mainly collected: 714 taxa be-

longing to Heteroptera, Coleoptera, Hymenoptera of suborder Symphyta and spiders were identified; out of them, 65 pro-

ved new to Lombardy, 5 new to Italy.

Key words: entomology, faunistics, Monte Barro.

L’indagine che il Museo di Storia Naturale di Mi¬

lano, col contributo del Consorzio Parco Monte Bar¬

ro, ha condotto nell’area del Monte Barro durante gli

anni 1989-1992 è stata prevalentemente orientata al

censimento di insetti fitofagi o comunque catturabili

coi sistemi in uso per la raccolta dell’entomofauna fi¬

tofaga. Sono stati studiati gli Eterotteri, alcune fami¬

glie di Coleotteri (Elateridi, Coccinellidi, Crisomeli¬

di, Cerambicidi, Curculionidi), gli Imenotteri Sinfiti e

i Ragni, con un numero complessivo di 718 entità si¬

stematiche, che risulta assai rilevante se si considera

che il Monte Barro è un rilievo molto modesto, privo

di specie strettamente orofile. Notevole è anche la se¬

gnalazione di ben 65 specie nuove per la Lombardia

e, nel caso dei Ragni, di 5 specie nuove per la fauna

italiana (v. Tabella 1).

Tabella 1 - Prospetto numerico delle specie raccolte

(n= n° di specie; L= specie nuove per la Lombardia;

1= specie nuove per l’Italia; %- percentuale di specie

raccolte rispetto a quelle note per ITtalia).

Le raccolte sono state effettuate prevalentemente

in 8 stazioni prative (staz. 1-8) all’interno del parco e

in una stazione (staz. 9) esterna, situata sulla riva set¬

tentrionale del bacino di Oggiono del Lago di Anno¬

ne, in località Ca’ si Sala.

Durante tutto il periodo delle raccolte è stata uti¬

lizzata per le stazioni 1-9 una numerazione differen¬

te, che riteniamo opportuno indicare in quanto non è

stata modificata sulle etichette che accompagnano gli

esemplari: 1 (4b), 2 (4), 3 (3), 4 (9), 5 (1 e Ibis), 6 (8),

7 (18), 8 (16), 9 (6).

Per una descrizione delle singole stazioni si ri¬

manda ai lavori di Banfi, Galasso & Sassi e Leonardi

& Sassi in questo stesso volume. Tali descrizioni si ri¬

feriscono agli anni in cui sono state effettuate le rac¬

colte.

Occorre infatti far presente che, essendo diventa¬

te più irregolari le tradizionali attività dell’economia

agro-silvo-pastorale che consentivano il manteni¬

mento delle cenosi erbacee, l’ambiente indagato ri¬

sulta oggi ampiamente caratterizzato da un dinami¬

smo verso la ricostruzione della foresta, quindi le va¬

riazioni che si osservano nei prati, quantomeno sotto

il profilo fisionomico, possono essere rapidissime, con

conseguenze sulla composizione dell’entomofauna. Il

recupero totale della foresta, con conseguente scom¬

parsa dei prati, causerebbe sicuramente un impoveri¬

mento faunistico.

Complessivamente sono state effettuate, da perso¬

nale o da collaboratori del museo, 86 uscite giornalie¬

re con un totale di 202 sopralluoghi di circa un’ora e

mezza ciascuno nelle stazioni 1-9, ripartiti come in ta¬

bella 2.

154

CARLO LEONARDI

Tabella 2 - Numero di sopralluoghi effettuati nei dif¬

ferenti mesi dell’anno nelle stazioni 1-9.

A queste uscite ne vanno aggiunte poche altre ef¬

fettuate da due studentesse nell’ambito delle loro te¬

si di laurea sui Ragni e sui Curculionidi del Monte

Barro.

Il numero di specie raccolto nelle singole stazioni

per ognuno dei gruppi studiati è riportato nella ta¬

bella 3.

Tabella 3 - Prospetto numerico delle specie raccolte

nelle stazioni 1-9.

L’area più ricca di specie, per quanto riguarda il

complesso dei gruppi studiati, sembra essere quella

che comprende la stazione 2, in località Piani di Bar¬

ra, interessata da scavi archeologici. Altre stazioni di

rilievo per l’elevato numero di specie che vi è stato

censito sono la staz. 3 (conca prativa a monte del mo¬

numento dell’Alpino, assai vicina in linea d’aria alle

stazioni 1 e 2), la staz. 4 (prato falciabile in località

San Michele) e la staz. 5 (in località Pian Sciresa),

mentre sembrano relativamente poveri i prati della

vai Faè (stazz. 7 e 8). È ovvio tuttavia che il numero

di specie censite nelle singole stazioni fornisce di per

sè un’informazione modesta se non lo si collega al

numero di uscite effettuate e soprattutto, ove possibi¬

le, all’andamento dei diagrammi di saturazione; que¬

sti ultimi sono stati costruiti solo per i Crisomelidi (v.

Leonardi & Sassi: p. 191, Fig 2), in considerazione del

fatto che a questo gruppo è stata rivolta una maggio¬

re attenzione durante le raccolte.

La descrizione di una comunità semplicemente in

termini di numero di specie presenti fa trascurare

completamente un aspetto importante della sua

struttura numerica, cioè la diversità. Alcune misure di

diversità (indice di Shannon, evenness, curve di k-do-

minanza) sono state ricavate per i Crisomelidi (v.

Leonardi & Sassi: pp. XX, Figg. 4, 5).

È infine interessante confrontare le stazioni 1-8 in

base alle specie fitofaghe che vi sono presenti. Par¬

tendo da una matrice binaria (Tab. 4) in cui sono rias¬

sunti i dati relativi ai tre gruppi (Heteroptera, Curcu-

lionidae, Chrysomelidae) più importanti e meglio

raccolti, si ricava, utilizzando l’indice di Dice/Soren-

sen e applicando la cluster analysis secondo il meto¬

do WPGMA, il dendrogramma di somiglianza ripor¬

tato in Fig. 1. In questo dendrogramma si nota l’isola¬

mento delle stazioni 7-8 che corrispondono a due

prati falciabili della Val Faè e, fra le rimanenti, la se¬

parazione della stazione 6, fisionomicamente ben ca¬

ratterizzata dall’evidente discontinuità della copertu¬

ra erbacea, che indica una forte ripresa del bosco.

Dal punto di vista zoogeografico l’entomofauna

del Monte Barro, che presenta una tipologia climati¬

ca di tipo insubrico, sembra essere caratterizzata da

una netta dominanza di taxa ad ampia distribuzione,

da una presenza importante di elementi europei e da

una scarsissima componente mediterranea, come si

vede nella Fig. 2 dove sono posti a confronto i gruppi

studiati raggruppando i corotipi per categorie sinteti¬

che (Vigna Taglianti et al., 1991).

i - 1 - - - 1 - 1 - 1

0.42 0.57 0.71 0.86 1.00

Fig. 1 - Dendrogramma di somiglianza delle stazioni 1-8 (indice di

Dice/Sorensen + WPGMA).

RICERCA ENTOMOFAUNISTICA NEL PARCO REGIONALE DEL MONTE BARRO

155

Ragni Eterotteri Cerambicidi Coccinellidi Crisomelidi Curculionidi Elateridi Sinfiti

E3 AMPIA DISTR. ■ DISTR. EUROPEA □ DISTR. MEDIT.

Fig. 2 - Spettro corologico nei gruppi studiati, con evidenziazione

di tre categorie sintetiche: elementi ad ampia distribuzione pa¬

leartica, elementi a distribuzione europea, elementi a distribuzio¬

ne mediterranea.

Complessivamente gli elementi ad ampia distribu¬

zione (per lo più asiatico-europei, sibirico-europei o

turanico-europei) sono circa il 66% e quelli a distri¬

buzione europea (comprendendovi anche i pochi en-

demiti della fauna italiana) poco più del 30%, mentre

la componente mediterranea corrisponde a meno del

2% delle specie raccolte (Fig. 3).

Medit.

1,82%

Fig.3 - Corotipi dei taxa raccolti sul Monte Barro raggruppati per

categorie sintetiche.

Tabella 4 - Matrice binaria formata da 395 specie di

Heteroptera (sono state escluse le specie predatrici),

Chrysomelidae e Curculionidae raccolti nelle stazio¬

ni 1-8.

156

CARLO LEONARDI

RICERCA ENTOMOFAUNISTICA NEL PARCO REGIONALE DEL MONTE BARRO

157

158

CARLO LEONARDI

BIBLIOGRAFIA

Leonardi C. & Sassi D., 1997 - 1 Crisomelidi (Coleoptera Chryso-

melidae) del Monte Barro (Italia, Lombardia, Lecco). Memo¬

rie Soc. it. Sci. nat. e Museo civ. Stor. nat. Milano, XXVII (II):

189-227.

Vigna Taglianti A., Audisio P.A., Belfiore G, Biondi M„ Bo¬

logna M.A., Carpaneto G.M., De Biase A., De Felici S.,

Piattella E., Racheli T„ Zapparoli M. & Zoia S. - 1992.

Riflessioni di gruppo sui corotipi fondamentali della fauna

W-paleartica ed in particolare italiana. Biogeographia , 16:

159-179.

Carlo Leonardi: Museo Civico di Storia Naturale, Sezione Botanica, Corso Venezia 55, 20121 Milano

Studi geobotanici ed entomofaunistici nel Parco Regionale del Monte Barro

Memorie della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano

Volume XXVII - Fascicolo II - 1997

Paride Dioli

Gli Eterotteri (Heteroptera) del Monte Barro

(Italia, Lombardia, Lecco)

Riassunto - Nel corso di una ricerca sugli Eterotteri del Monte Barro sono state censite 169 specie, di cui 13 vengono

segnalate per la prima volta in Lombardia. Esse sono: Bothynotus pilosus, Dicyphus annulatus, Phytocoris dimidiatus Pina-

htusatomanus Heterocordylus tumidicornis, Globiceps horvathi, Driophylocoris flavoquadrimaculatus, Harpocera thoraci-

ca, Heterocapdlus tigripes, Berytinus minor, Berytinus clavipes, Heterogaster cathariae e Megalonotus dilatatus. Sono state

inoltre confrontate mediante una cluster analysis le nove principali stazioni di campionamento delle specie. Dal punto di vi¬

sta zoogeografico è emerso che la maggior parte delle specie presenta ampia distribuzione in Asia ed Europa mentre l’e¬

lemento mediterraneo è scarsamente rappresentato, anche in relazione all’assenza di piante ospiti stenomediterranee.

Abstract - Bugs (Heteroptera) from Monte Barro (Italy, Lombardy, Lecco).

As a result of a research on thè heteropteran fauna (Inserta, Heteroptera) of thè Monte Barro (Lombardia, Italy) 169

species have been recorded: thirteen of them ( Bothynotus pilosus, Dicyphus annulatus, Phytocoris dimidiatus, Pinalitus ato-

marius, Heterocordylus tumidicornis, Globiceps horvathi, Driophylocoris flavo quadrimaculatus, Harpocera thoracica, Hete-

rocapillus tigripes, Berytinus minor, Berytinus clavipes, Heterogaster cathariae and Megalonotus dilatatus ) are new for Lom¬

bardia. The main sampling sites (sites 1-9) have been compared through a cluster analysis. The biogeographical analysis of

thè whole heteropteran fauna has been accomplished: most species are large distributed in Asia and Europe. The number

of Mediterranean elements is unimportant, owing to thè absence of thè typical Mediterranean host plants.

Key words: Monte Barro, Heteroptera, geographical distribution.

Negli anni 1989-1992 il Museo di Milano, con l’ap¬

poggio del Consorzio del Parco, ha effettuato una se¬

rie di raccolte sul Monte Barro, tese soprattutto allo

studio degli insetti legati alla vegetazione dei prati e

delle boscaglie circostanti. I campionamenti sono sta¬

ti effettuati inizialmente in numerose stazioni, e, suc¬

cessivamente, concentrati in nove stazioni prative

scelte fra quelle maggiormente rappresentative. Fra

queste ultime, otto sono ubicate entro i confini del

Parco e una immediatamente all’esterno (in località

Ca’ di Sala).

Tra il copioso materiale raccolto, conservato pres¬

so il Museo di Storia Naturale di Milano, vi è anche

un lotto di Eterotteri che sono stati preparati a secco

oppure conservati in acetone.

L’esame di questo materiale ha portato alla iden¬

tificazione di 169 specie, tra le quali 13 entità che non

erano state ancora segnalate in Lombardia oppure la

cui presenza era dubbia anche alla luce di alcune re¬

centi revisioni dei rispettivi gruppi sistematici. Esse

sono: Bothynotus pilosus, Dicyphus annulatus, Phyto-

coris dimidiatus, Pinalitus atomarius, Heterocordylus

tumidicornis, Globiceps horvathi, Driophylocoris fla¬

vo quadrimaculatus, Harpocera thoracica, Heteroca-

pillus tigripes, Berytinus minor, Berytinus clavipes,

Heterogaster cathariae e Megalonotus dilatatus.

Ma, ciò che più conta, è che la fauna eterotterolo-

gica del Monte Barro può considerarsi a tutt’oggi suf¬

ficientemente indagata; il cospicuo numero di specie

1 censite, in rapporto all’esigua estensione del Parco,

! rende merito alla Direzione del medesimo per aver

creduto in questa ricerca.

Descrizione sommaria delle Stazioni di raccolta 1-9

Staz. 1 - Sito archeologico in località Piani di Bar¬

ra, con calpestìo al centro e bosco ai margini; consi¬

stente l’elemento prativo con attività di foraggio resi¬

dua. Specie vegetali interessanti per gli Eterotteri:

Dactylis glomerata, Centaurea nigrescens, Trifolium

repens, Achillea spp., Lolium perenne, Vicia spp., The-

sium bavaricum.

Staz. 2 - Sito archeologico in località Piani di Bar¬

ra, un po’ a valle rispetto alla staz. 1; leggera preva¬

lenza di prateria e mantello su prato falciabile, come

risposta all’abbandono di una gestione a foraggio già

indebolita. Specie vegetali interessanti per gli Eterot¬

teri: Galium verum, Geranium sanguineum, Festuca

rubra, Valeriana collina, Vicia sepium, Teucrium cha-

maedrys, T.montanum, Vincetoxicum hirsutum.

Staz. 3 - Conca prativa a monte del Monumento

dell’alpino, convivenza di prateria con elementi di

prato falciabile ed elementi di disturbo marginale.

Specie vegetali interessanti per gli Eterotteri: Achil¬

lea sp., Centaurea spp., Euphorbia cyparissias, Galium

album, Gtverum, Lathyrus pratensis, Verbascum tha-

psus, Vicia spp.

Staz. 4 - Pendio in località S. Michele, in prossimità

del sentiero per Pian Sciresa. Prato falciabile in pieno

sviluppo con carattere oligo-mesotrofico. Specie ve¬

getali interessanti per gli Eterotteri: Echium vulgare,

Arabis collina, Daucus carota, Peucedanum spp., Vin¬

cetoxicum hirsutum.

Staz. 5 - Pian Sciresa, prato arido con collinetta a

brughiera. Inoltre si nota la presenza di prateria a

160

PARIDE DIOLI

Brachypodium rupestre. Specie vegetali interessanti

per gli Eterotteri: Collima vulgaris, Genista germani¬

ca, Hieracium sabaudum, Populus tremula, Cytisus

emeriflorus, C. scoparius.

Staz. 6 - Sentiero per la vetta del M. Barro, sopra

l’eremo. Si tratta di una prateria con parziale affiora¬

mento roccioso, fortemente cespugliata e in via di

chiusura, con una notevole presenza dell’elemento

pre-nemorale e tendenza a Quercetum pubescentis

s.l.. Specie vegetali interessanti per gli Eterotteri:

Centaurea spp., Corylus avellana, Euphorbia spp.,

Fraxinus ornus, Origanum volgare, Ostrya carpinifo-

lia, Teucrium montanum, T. chamaedrys, Thesium

spp., Vincetoxicum spp.

Staz. 7 - Località Fornaci Villa, terrazzo inferiore.

Prato contornato da bosco con caratteristiche simili a

quelle della stazione 8, ma con specie vegetali più

eliofile. Specie vegetali interessanti per gli Eterotteri:

Achillea spp., Trifolium spp., Galium mollugo, Hera-

cleum spp., Medicago spp., Peucedanum spp., Pimpi¬

nella spp., Trifolium spp., Vicia spp.

Staz. 8 - Località Fornaci Villa, terrazzo superiore.

Prato irregolarmente gestito e contornato da un bo¬

sco con notevoli contrassegni mesofili ( Astrantia

major, Prunus avium, Geranium nodosurn ), in conse¬

guenza dell’esposizione a Nord - Ovest e dell’ele¬

mento sciafilo. Specie vegetali interessanti per gli

Eterotteri: Arrenatherum elatior, Astrantia major,

Brachypodium rupestre cespitosum, Ononis spinosa.

Staz. 9 - Superficie prativa al bordo settentrionale

del Lago di Annone. Si rilevano aspetti di canneto,

prato umido oligotrofico e vegetazione disorganizza¬

ta al marginme esterno.

Tabella 1 - Prospetto delle specie raccolte (in neretto le specie esclusivamente o prevalentemente

predatrici). Sotto il numero 10 sono raggruppate diverse stazioni nelle quali le raccolte hanno avuto

carattere di sporadicità. A = abbondante.

GLI ETEROTTERI (HETEROPTERA) DEL MONTE BARRO (ITALIA. LOMBARDIA, LECCO)

161

162

PARIDE DIOLI

L’analisi del popolamento emitterologico viene

fatta attraverso l’individuazione dei rapporti gerar¬

chici di somiglianza fra le prime nove stazioni di rac¬

colta degli eterotteri. Tali rapporti sono evidenziati

nel dendrogramma di Fig. 5 che è stato ottenuto uti¬

lizzando l’indice di Sorensen e la cluster analysis se¬

condo il metodo WPGMA. La matrice per l’analisi,

che qui non si riporta, è facilmente ricavabile dalla ta¬

bella soprastante.

Come si può osservare, le Staz. 1, 2, 3, 4 fanno

gruppo assieme e rappresentano un «cluster» ben

identificato dalle situazioni a prato degradato che ri¬

chiamano eterotteri antropofili.

La Staz. 5 si stacca nettamente per la presenza del¬

la tipica fauna degli eterotteri di brughiera.

La Staz. 6 (sotto la vetta del Barro) è quella più

povera di specie (forse a causa di una certa ventosità)

ed è perciò molto distante dalla precedente.

Le Staz. 7 e 8 hanno invece una somiglianza che

viene molto ben enfatizzata dal dendrogramma.

Guardando la situazione in loco, scopriamo infatti

che esse sono entrambe caratterizzate dalla vicinanza

della faggeta, un fattore che risulta determinante an¬

che in altri studi entomologici di questa serie sul Par¬

co del Barro.

La Staz. 9, infine, pur avendo delle affinità con il

primo gruppo (1, 2, 3, 4) se ne discosta in forza della

presenza di alcuni elementi igrofili legati alle specie

vegetali tipiche di ambienti umidi.

Discussione delle specie

Saldidae

1. Saldula sai tatoria (Linné, 1758)

Corotipo: Olartico (OLA).

Presenza in Italia: tutte le regioni settentrionali,

meno frequente al Sud dove è presente solo in mon¬

tagna.

Biologia: predatore di microinvertebrati. Specie

opportunista che può adattarsi bene sia in riva a pic¬

coli ruscelli che sulle spiagge marine.

Tingidae

2. Kalama tricomis (Schrank, 1801)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutte le regioni.

Biologia: solitamente su Artemisia campestris.

3. Dictyonota strichnocera Fieber, 1844

Corotipo: Europeo (EUR).

Presenza in Italia: regioni settentrionali, qua e là

in quelle centro meridionali e in Sicilia, assente in

Sardegna.

Biologia: su Cytisus spp., Ulex europaeus, Genista

spp..

4. Lasiacantha capucina (Germar, 1836)

Corotipo: Centroasiatico-Europeo (CAE).

Presenza in Italia: regioni settentrionali e centrali,

sino all’Abruzzo.

Biologia: su Thymus spp., Salvia spp., Teucrium spp..

5. Tingis crispata (Herrich - Schaffer, 1838)

Corotipo: Centroasiatico-Europeo (CAE).

Presenza in Italia: regioni settentrionali.

Biologia: Arthemisia spp..

6. Tingis reticulata (Herrich - Schaffer, 1835)

Corotipo: Centroeuropeo (CEU).

Presenza in Italia: regioni settentrionali e centrali.

Biologia: Ajuga spp..

Note di raccolta: l’insetto è stato raccolto in un

prato vicino alla staz. 4 (loc. S. Michele).

7. Catoplatus fabricii (Stai, 1868)

Corotipo: Centroeuropeo (CEU).

Presenza in Italia: regioni settentrionali. In quelle

centro-meridionali, solo in Abruzzo, Puglie e Basili¬

cata.

Biologia: su Leucanthemum vulgare, Chrysanthe-

mum spp.

8. Onchochila simplex (Herrich - Schaffer, 1830)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: nelle regioni settentrionali.

Biologia: su Euphorbia spp.

9. Dictyla echii (Schrank, 1782)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutte le regioni.

Biologia: Echium spp.

10. Copium clavicome (Linné, 1758)

Corotipo: S-Europeo (SEU).

Presenza in Italia: regioni settentrionali e, scen¬

dendo al Sud, sull’Appennino.

Biologia: Teucrium chamaedrys.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto ai margini di un sentiero che dall’eremo

va alla Sella della Pila.

11. Agramma laetum (Fallén, 1807)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: regioni settentrionali, meno co¬

mune al centro-sud.

Biologia: in ambienti umidi su Juncus spp., Carex spp.

Miridae

12. Bothynotus pilosus (Boheman, 1852), Fig. 1

Corotipo: Europeo (EUR).

Presenza in Italia: segnalato di alcune regioni set¬

tentrionali (Piemonte, Liguria, Trentino, Friuli Vene¬

zia Giulia) e Sicilia. Prima citazione per la Lombardia.

Biologia: nelle radure e brughiere, più raramente

nei boschi di Pinus, generalmente legato a Calluna

vulgaris.

Note di raccolta: l’insetto è stato raccolto ai mar¬

gini di un sentiero che dall’eremo va alla Sella della

Pila.

Note geonemiche: se si eccettua il dato più recen¬

te, relativo al Friuli, citato da Servadei (1967), le se¬

gnalazioni italiane per questa specie risalgono tutte al

secolo scorso. Considerando che il Bothynotus pilo¬

sus (Boheman, 1852) presenta la femmina brachitte-

ra, ne consegue una naturale propensione all’isola¬

mento e alla localizzazione in aree con calluneti relit¬

ti. In questo contesto, assume notevole importanza il

reperto proveniente dal Monte Barro, che potrebbe

configurarsi come stazione relitta per questa specie.

13. Briocoris pteridis Fallén, 1807

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: regioni alpine.

Biologia: su felci, particolarmente Pteridium aqui-

linum.

GLI ETEROTTERI (HETEROPTERA) DEL MONTE BARRO (ITALIA, LOMBARDIA, LECCO)

163

Corotipo: Turanico-Europeo-Mediterraneo (TEM).

Presenza in Italia: tutte le regioni.

Biologia: su svariate latifoglie ma anche aghifo¬

glie, infestate da afidi o psillidi.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto ai margini di un sentiero che che dall’ere¬

mo va alla Sella della Pila.

16. Deraeocoris serenus Douglas & Scott, 1868

Corotipo: Mediterraneo (MED).

Presenza in Italia: tutte le regioni.

Biologia: predatore di microinsetti su svariate

piante erbacee.

17. Dicyphus flavoviridis Tamanini, 1949

Corotipo: Endemico italiano (END).

Presenza in Italia: tutte le regioni.

Biologia: Rubus spp., Geranium spp., Galeopsis

spp..

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto nel sottobosco della Val Faè.

18. Dicyphus globulifer (Fallén, 1829)

Corotipo: Europeo (EUR).

Presenza in Italia: tutte le regioni.

Biologia: su Chrysanthemum spp., Lycnis spp., Me-

landryum spp., Ononis spp.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto in un prato presso Camporeso.

19. Dicyphus annulatus (Wolff 1804)

Corotipo: Europeo (EUR).

Presenza in Italia: nelle regioni settentrionali è spo¬

radica e si hanno dati certi solo di Piemonte e Liguria.

Più comune al Sud, ma la sua distribuzione necessita di

conferma dopo la separazione da D. ononidis E. Wa¬

gner, 1951. Prima citazione per la Lombardia.

Biologia: su Ononis spinosa.

Note sistematiche: D. annulatus si distingue da D.

ononidis E.Wagn, 1951, per le dimensioni del secon¬

do articolo antennale decisamente più corto. Esso è

infatti di poco più lungo del terzo e la metà della lar¬

ghezza del pronoto. D. ononidis ha invece il secondo

articolo antennale che è 0,7-0,8 volte la larghezza del

pronoto.

20. Stenodema sericans (Fieber, 1861)

Corotipo: Centroeuropeo (CEU).

Presenza in Italia: regioni settentrionali e, alle

quote più elevate, in quelle appenniniche e in Sicilia.

Biologia: poacee.

Note di raccolta: l’insetto è stato raccolto ai margi¬

ni di un sentiero che dall’eremo va alla Sella della Pila.

21 .Stenodema calcaratum (Fallén, 1807)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutte le regioni.

Biologia: su diverse Poacee.

22. Stenodema laevigatum (Linné, 1758)

Corotipo: Olartico (OLA).

Presenza in Italia: tutte le regioni.

Biologia: poacee (spesso svernante su conifere).

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto nel sottobosco della Val Faè.

23. Trigonotylus ruficornis (Geoffroy, 1785)

Corotipo: Olartco (OLA).

Presenza in Italia: tutte le regioni.

Biologia: su poacee, preferibilmente in ambienti

umidi.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto in un prato vicino alla staz. 4 (loc. S. Mi¬

chele).

24. Notostira erratica (Linné, 1758)

Corotipo: Europeo (EUR).

Presenza in Italia: tutte le regioni.

Biologia: poacee.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto nel sottobosco della Val Faè.

25. Megaloceroea recticornis (Geoffroy, 1785)

Corotipo: Europeo - Mediterraneo (EUM).

Presenza in Italia: tutte le regioni.

Biologia: Poacee, preferibilmente Triticum spp..

26 . Phytocoris dimidiatus (Kirschbaum, 1856)

Corotipo: Europeo - Mediterraneo (EUM).

Presenza in Italia: Piemonte, Liguria, Trentino, La¬

zio e Sicilia. Prima segnalazione per la Lombardia.

Biologia: predatore di microinsetti su latifoglie

(Pirus, Malus, Quercus ), ma anche su Pinus spp..

27 . Adelphocoris lineolatus (Goeze, 1778)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutte le regioni.

Biologia: Artemisia spp., Verbascum spp.. Achillea

spp., Medicago spp.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto in un prato presso Camporeso.

164

PARIDE DIOLI

28. Adelphocoris seticomis (Fabricius, 1775)

Corotipoo: Sibirico-Europeo (SIE).

Presenza in Italia: tutte le regioni. Dubbia la pre¬

senza sulle isole maggiori (Faraci & Rizzotti, 1995).

Biologia: su papilionacee, come Medicaio spp.,

Trifolium spp., Vi eia spp.. Adulti soprattutto in luglio

e agosto.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto sulla vegetazione ai margini della strada

asfaltata che sale verso il Monumento all’Alpino.

29. Adelphocoris vandalicus (Rossi, 1790)

Corotipo: Mediterraneo (MED).

Presenza in Italia: tutte le regioni, ma raro in quel¬

le alpine

Biologia: Verbascum spp., Achillea spp., Arthemi-

sia spp.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto ai margini di un sentiero che dall'eremo

va alla Sella d. Pila.

30. Calocoris striatellus (Fabricius, 1794) (= C. qua-

dripunctatus. Vili., 1789)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutte le regioni.

Biologia: su Quercus sp., dove si comporta talora

da zoofago, talora da fitofago.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto ai margini di un sentiero che dall’eremo

va alla Sella della Pila.

31. Stenotus binotatus (Fabricius, 1794)

Corotipo: Olartico (OLA).

Presenza in Italia: tutte le regioni, tranne la Sarde¬

gna.

Biologia: Melilotus spp., Medicago spp..

32. Pantilius tunicatus (Fabricius, 1781)

Corotipo: Europeo (EUR).

Presenza in Italia: regioni settentrionali, raro al

Sud.

Biologia: Betula spp., Corylus spp.

33. Exolygus pratensis (Linné, 1758)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: tutte le regioni.

Biologia: su svariate piante erbacee tra cui Unica

spp., Artemisia spp., Stachys spp. e Mentha spp.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto in un prato vicino alla staz. 4 (loc. S. Mi¬

chele).

34. Pinalitus atomarius (Meyer - Dur, 1843)

Corotipo: S-Europeo (SEU).

Presenza in Italia: Trentino, Piemonte, Emilia, La¬

zio e Calabria. Prima segnalazione per la Lombardia.

Biologia: sulle conifere.

35. Orthops kalmi (Linné, 1758)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutte le regioni.

Biologia: su Apiacee come Peucedanum spp., Pim¬

pinella spp., Daucus spp., Pastinaca spp. ecc.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto nei prati sotto Sella d. Pila, a circa 700 m

di quota.

36. Liocoris tripustulatus (Fabricius, 1781)

Corotipo: Paleartica (PAL).

Presenza in Italia: tutte le regioni.

Biologia: su Parietaria spp., Solanum spp., Unica

spp., Verbascum spp., Salvia spp.

37. Polymerus holosericeus (Hahn, 1831)

Corotipo: Turanico-Mediterraneo (TUM).

Presenza in Italia:regioni montane delle Alpi e

dell’Appennino, sino alla Campania.

Biologia: su Unica spp. e Galium spp.

38. Polymerus unifasciatus (Fabricius, 1794)

Corotipo: Olartico (OLA).

Presenza in Italia: tutte le regioni.

Biologia: Galium sp.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto ai margini di un sentiero che dall’eremo

va alla Sella della Pila.

39. Capsus ater (Linné, 1758)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutte le regioni.

Biologia: su Phleum spp.

40. Halticus apterus (Linné, 1758)

Corotipo: Turanico-Europeo-Mediterraneo (TEM).

Presenza in Italia: tutte le regioni.

Biologia: Ononis spp., Galium spp.

41. Heterocordylus genistae (Scopoli, 1763)

Corotipo: Europeo (EUR).

Presenza in Italia: regioni settentrionali, centro¬

meridionali e Sardegna.

Biologia: Genista spp.; regime dietetico solo par¬

zialmente fitofago.

42. Heterocordylus tumidicomis (Herrich - Schaffer,

1836)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: diverse regioni settentrionali,

centrali e meridionali. Prima segnalazione per la

Lombardia.

Biologia: soprattutto su Prunus spp.e Mespilus

germanica , ma anche su Alnus spp., Euonimus euro-

paeus e Sarothamnus scoparius; regime dietetico solo

parzialmente fitofago.

43. Globiceps horvathi Reuter, 1912

Corotipo: Est-Mediterraneo (EME).

Presenza in Italia: le citazioni sicure sono di Pie¬

monte, Trentino, Alto Adige, Marche, Abruzzo, Cam¬

pania, Calabria e Sicilia. Prima segnalazione per la

Lombardia.

Biologia: su Ononis spp., Spartium spp., Galium

spp., Corylus spp., Crataegus spp.

44. Globiceps shaegiformis (Rossi, 1790)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutte le regioni.

Biologia: soprattutto su Quercus spp., ma talora

anche su Acer campestre e Corylus avellana.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto ai margini di un sentiero che dall’eremo

va alla Sella della Pila.

45. Driophylocoris flavoquadrimaculatus (De Geer,

1773)

Corotipo: Europeo-Mediterraneo (EUM).

GLI ETEROTTERI (HETEROPTERA) DEL MONTE BARRO (ITALIA, LOMBARDIA, LECCO)

165

Presenza in Italia: si hanno segnalazioni sicure di

Piemonte, Trentino, Alto Adige, Veneto, Emilia, Um¬

bria, Lazio, Puglia e Sicilia. Prima segnalazione per la

Lombardia.

Biologia: fitofago e zoofago su Quercus spp.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto ai margini di un sentiero che dall’eremo va

alla Sella della Pila e in un prato presso Camporeso.

46. Cyllecoris histrionicus (Linné, 1767)

Corotipo: Europeo (EUR).

Presenza in Italia: tutte le regioni.

Biologia: su Quercus sp.; regime dietetico zoofago

e fitofago.

47. Pilophorus perplexus Dgl.& Scott, 1785 (= P.pu-

sillus Reuter, 1878)

Corotipo: Europeo - Mediterraneo (EUM).

Presenza in Italia: tutte le regioni.

Biologia: predatore di afidi su Prunus spp .Junipe-

rus spp. e Alnus glutinosa.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto ai margini di un sentiero che dall’eremo

va alla Sella della Pila.

48. Pilophorus clavatus (Linné, 1767)

Corotipo: Olartico (OLA).

Presenza in Italia: regioni centro settentrionali,

più raro al Sud.

Biologia: predatore di afidi su Populus spp.

49. Harpocera thoracica (Fallén, 1807)

Corotipo: Turanico-Europeo-Mediterraneo (TEM).

Presenza in Italia: Piemonte, Veneto, Friuli-Vene¬

zia Giulia, Liguria, Umbria e Sicilia. Prima segnala¬

zione per la Lombardia.

Biologia: su Quercus; forme giovanili essenzial¬

mente fitofaghe, adulti anche predatori di microinset¬

ti; nelle Prealpi legato al « Querco-Betuletum insubri-

cum » (Dioli, 1993).

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto in un prato presso Camporeso.

50. Phylus coryli (Linné, 1758)

Corotipo: Europeo (EUR).

Presenza in Italia: tutte le regioni settentrionali,

centro-meridionali e Sicilia.

Biologia: su Corylus avellana , anche predatore di

microinsetti.

51. Chlamidatus pulicarius (Fallén, 1807)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutte le regioni settentrionali e

[ lungo l’Appennino sino al Molise.

Biologia: su Artemisia spp.. Achillea spp.

52. Plagiognathus arbustorum (Fabricius, 1794)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutte le regioni.

Biologia: comune soprattutto su Urtica spp.

Note di raccolta: l'insetto è stato raccolto ai margini

di un sentiero che dall’eremo va alla Sella della Pila.

53. Criocoris crassicomis (Hahn, 1834)

Corotipo: Turanico-Europeo-Mediterraneo (TEM).

Presenza in Italia: regioni settentrionali, Emilia,

Liguria, Umbria, Abruzzo e Sicilia.

Biologia: su Galium spp.

54. Heterocapillus tigripes (Mulsant, 1852)

Corotipo: Europeo (EUR).

Presenza in Italia: regioni settentrionali, Emilia,

Toscana, Abruzzo e Molise, Campania, Basilicata e

Calabria. Prima segnalazione per la Lombardia.

Biologia: su Dorycnium spp.

Note di raccolta: l’insetto è stato raccolto ai margi¬

ni di un sentiero che dall'eremo va alla Sella della Pila.

55. Psallus variabilis (Fallén, 1807)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Trentino, Alto Adige, Veneto,

Lombardia, Piemonte, Emilia, Calabria, Puglia.

Biologia: su Prunus spinosa.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto nei prati sotto la Sella della Pila.

56. Charagochilus gyllenhali (Fallén, 1807)

Corotipo: Paleartico (PAL).

Presenza in Italia: Piemonte, Lombardia, Alto

Adige, Trentino, Veneto, Emilia, Marche, Umbria,

Abruzzo, Calabria, Sicilia.

Biologia: su Galium spp.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto in un prato della Val Faè attiguo alla staz.

7, in un prato in località S. Michele vicino alla staz. 4

e in un prato vicino a Camporeso.

57. Charagochilus weberi E. Wagner, 1953

Corotipo: Europeo (EUR).

Presenza in Italia: Piemonte, Lombardia, Alto

Adige, Veneto, Marche, Umbria, Abruzzo, Campania,

Puglie, Sicilia e Montecristo.

Biologia: su Verbascum spp.

Nabidae

58. Prostemma aeneicolle Stein, 1857

Corotipo: Europeo (EUR).

Presenza in Italia: Trentino, Alto Adige, Lombar¬

dia, Veneto, Liguria, Emilia, Toscana, Abruzzo e Mo¬

lise, Calabria.

Biologia: prevalentemente predatore di eterotteri

ligeidi e pentatomidi.

59. Himacerus apterus (Fabricius, 1798)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: regioni settentrionali e centrali,

raro al Sud.

Biologia: si nutre prevalentemente di afidi e larve

di lepidotteri sulle latifoglie.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto nel sottobosco della Val Faè.

60. Aptus mirmicoides (O.Costa, 1834)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutte le regioni.

Biologia: predatore di microinsetti su erbe basse e

arbusti.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto nei prati sotto la Sella della Pila, in un pra¬

to della vai Faè vicino alla staz. 7, lungo un sentiero

che dall’eremo conduce alla Sella della Pila e in un

prato presso Camporeso.

61. Nabis rugosus (Linné, 1758)

Corotipo: Sibirico-Europeo-Mediterraneo (SEM).

Presenza in Italia: regioni alpine, più raro in quel¬

le appenniniche, assente nelle isole.

166

PARIDE DIOLI

Biologia: predatore di afidi e microinsetti, gene¬

ralmente su Artemisia spp. ed Erica spp.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto in un prato vicino a Camporeso.

62. Nabis punctatus (Costa, 1847)

Corotipo: S-Europeo (SEU).

Presenza in Italia: tutte le regioni.

Biologia: predatore di microinsetti sulle erbe bas¬

se e sugli arbusti, spesso associato a Stenodema spp.

Anthocoridae

63 . Anthocoris confusus Reuter, 1884

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: regioni alpine, Emilia, Umbria,

Lazio, Abruzzo e Molise, Basilicata, Sicilia.

Biologia: predatore di microinsetti su Betula spp. e

Fagus spp.

64. Anthocoris nemoralis (Fabricius, 1794)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutte le regioni.

Biologia: predatore di microinsetti, specialmente

psille e afidi, su Crataegus spp., Sorbus spp., Euphor-

bia spp., Fraxinus spp., Populus spp., Rhamnus spp.,

Prumis spp.

65. Anthocoris nemorum (Linné, 1761)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: tutte le regioni.

Biologia: predatore di psillidi e afidi su Picea spp.,

Alnus spp., Salix spp., ma anche su piante erbacee co¬

me Urtica spp. e Daucus carota.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto lungo un sentiero che dall’eremo conduce

alla Sella della Pila.

66. Orius majusculus (Reuter, 1879)

Corotipo: Europeo (EUR).

Presenza in Italia: Piemonte, Lombardia, Trentino,

Alto Adige, Veneto, Emilia, Marche, Toscana, Abruz¬

zo, Calabria, Sardegna.

Biologia: predatore di microinsetti (afidi, larve di

microlepidotteri) e acari, soprattutto in ambienti

umidi su Polygonum spp., Phragmites spp. e Care x

spp.

67. Orius niger (Wolff, 1811)

Corotipo: Turanico-Europeo-Mediterraneo (TEM).

Presenza in Italia: tutte le regioni.

Biologia: predatore di microinsetti (afidi, tisanot-

teri) e acari su Artemisia spp., Achillea spp., Verba-

scum spp.

Phymatidae

68. Phymata crassipes (Fabricius, 1775)

Corotipo: Sibirico-Europeo-Mediterraneo (SEM).

Presenza in Italia: tutte le regioni.

Biologia: predatore, generalmente sui fiori o tra le

erbe secche in ambienti soleggiati.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto lungo un sentiero che dall’eremo conduce

alla Sella d. Pila.

Reduviidae

69. Rhynocoris iracundus (Poda, 1761)

Corotipo: Sibirico-Europeo-Mediterraneo (SEM).

Presenza in Italia: tutte le regioni, anche in mon¬

tagna. Meritano conferma le segnalazioni per la Sar¬

degna.

Biologia: predatore di invertebrati.

70. Rhynocoris annulatus (Linné, 1758)

Corotipo: Sibirica-Europeo (SIE).

Presenza in Italia: tutte le regioni dalle Alpi alla

Calabria. Dubbia la presenza in Sicilia, assente in Sar¬

degna.

Biologia: predatore di invertebrati, è la specie di

Rhynocoris che si spinge più in alto in montagna: nel¬

la zona alpina è stato trovato a 2500 metri di altezza

(Passo Forcola di Livigno), in ambienti asciutti e

steppici.

Aradidae

IX.Aradus depressus (Fabricius, 1794)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutte le regioni peninsulari e la

Sicilia.

Biologia: si nutre del micelio e dei corpi fruttiferi

di poliporacee attaccate a Betula, Quercus e Fagus.

Berytidae

72. Berytinus minor (Herrich - Schaffer, 1835)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Piemonte, Trentino, Alto Adige,

Emilia, Abruzzo, Lazio, Sardegna. Prima segnalazio¬

ne per la Lombardia.

Biologia: specie legata principalmente a Trifolium

spp. e Medicago spp.

73. Berytinus clavipes (Fabricius, 1775)

Corotipo: Sibirico - Europeo (SIE).

Presenza in Italia: Piemonte, Trentino, Veneto,

Emilia, Toscana. Prima segnalazione certa per la

Lombardia, dopo la revisione di Pericart (1984).

Biologia: Ononis spp., Vicia spp.

Lygaeidae

74. Tropidothorax leucopterus (Goeze, 1778)

Corotipo: Turanico-Europeo-Mediterraneo (TEM).

Presenza in Italia: tutte le regioni.

Biologia: su Vincetoxicum spp. e Cynanchum spp..

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto lungo un sentiero che dall’eremo conduce

alla Sella d. Pila e in un prato vicino a Camporeso.

75. Lygaeus equestris (Linné, 1758)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutte le regioni, tranne la Sicilia.

Biologia: in prevalenza su Artemisia, Achillea, Me¬

dicago, Trifolium, Scrophularia e Datura.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto nei prati sotto la Sella della Pila (m 700),

nei boschi della Val Faè e lungo un sentiero che dal¬

l’eremo conduce alla Sella della Pila.

Note geonemiche: la descrizione recente della

specie affine, Lygaeus simulans (Deckert, 1985), ha

portato ad una ridefinizione della distribuzione gene¬

rale di L. equestris, sotto il cui nome erano precen-

dentemente confuse le due entità.

L. simulans, in Italia, si comporta come elemento

prevalentemente montano nelle Alpi e sull’Appenni-

no mentre L. equestris è specie più ubiquista.

Note sistematiche: il carattere che consente l’im-

GLI ETEROTTERI (HETEROPTERA) DEL MONTE BARRO (ITALIA. LOMBARDIA. LECCO)

167

mediata separazione delle due specie risiede nello

scutello: glabro o con micro-peli in L. equestri, irsu¬

to con peli lunghi ed eretti in L. simulans. Interessan¬

te anche la possibilità di facile separazione delle due

specie negli stadi larvali: su Cynanchum sono state

osservate neanidi del 5° stadio di L. simulans (color

avorio con striature rosse) e di L. equestris (comple¬

tamente rosse). (Melber & Coll., 1991).

76. Lygaeus saxatilis (Scopoli, 1763)

Corotipo: Turanico-Europeo-Mediterraneo (TEM).

Presenza in Italia: tutte le regioni.

Biologia: specialmente su Colchicum autumnale.

77. Nysius senecionis (Schilling, 1828)

Corotipo: Turanico-mediterraneo-Europeo (TEM).

Presenza in Italia: tutte le regioni, meno comune

al Sud.

Biologia: su Artemisia absinthium.

78. Nysius ericae (Schilling, 1829)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: regioni settentrionali e, più spo¬

radico, in quelle meridionali.

Biologia: Artemisia spp.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto in un prato vicino a Camporeso.

79. Nysius thymi (Wolff, 1804)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: tutte le regioni, al Sud, solo sui

monti.

Biologia: Artemisia spp.

80. Kleidocerys reseda e (Panzer, 1789)

Corotipo: Sibirico-Europeo (SIE) e Neartico.

Presenza in Italia: regioni settentrionali, Emilia e

Toscana.

Biologia: Betula spp., Calluna vulgaris.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto in un prato della vai Faè vicino alla staz. 7.

81. Cymus aurescens Distant, 1883 (= obliquus Hor-

vath, 1888)

Corotipo: Centroeuropeo (CEU).

Presenza in Italia: Piemonte, Lombardia, Trentino

e Liguria.

Biologia: su Scirpus spp.

82. Ischnodemus quadratus (Fieber, 1836)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutte le regioni italiane

Biologia: poacee, in zone umide o paludose.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto in un prato vicino alla staz. 4.

83. Geocoris megacephalus (Rossi, 1790)

Corotipo: Turanico-Europeo-Mediterraneo (TEM).

Presenza in Italia: tutte le regioni. Le vecchie cita¬

zioni di G. siculus (Fieber) 1844, si riferiscono in

realtà a questa specie (Tamanini, 1981).

Biologia: detriti di Artemisia spp.

84. Oxycarenus pallens (Herrich - Schaffer, 1850)

Corotipo: Centroasiatico-Mediterraneo (CAM).

Presenza in Italia: tutte le regioni, raro nelle Alpi.

Biologia: su Centaurea spp.

85. Oxycarenus lavaterae (Fabricius, 1787)

Corotipo: Mediterraneo (MED).

Presenza in Italia: tutte le regioni, spesso in folte

colonie gregarie sulle piante ospiti, dove riesce tal¬

volta dannoso.

Biologia: soprattutto sul tiglio (Tilia cordata ), fito-

fago e, nei mesi invernali o di rifugio, corticicolo.

Note di raccolta: ne sono stati raccolti numerosi

esemplari in una radura sotto Teremo.

86. Macroplax preyssleri (Fieber, 1838)

Corotipo: Europeo (EUR).

Presenza in Italia: tutte le regioni peninsulari e Si¬

cilia, raro sulle Alpi.

Biologia: Thymus serpyllum.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto lungo un sentiero che dall’eremo conduce

alla Sella della Pila.

87. Macroplax fasciatus (Herrich - Schaffer, 1835)

Corotipo: Turanico-Europeo-Mediterraneo (TEM).

Presenza in Italia: tutte le regioni, al Sud sino a

2000 m.

Biologia: Ononis spp., Cistus spp., Spartium jun-

ceum.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto nei prati sotto la Sella d. Pila (m 700) e

lungo un sentiero che dall’eremo conduce alla Sella

della Pila.

88. Heterogaster cathariae (Geoffroy, 1785), Fig. 2

Corotipo: Turanico-Europeo-Mediterraneo (TEM).

Presenza in Italia: specie rara, sicuramente pre-

Fig. 2 - Heterogaster cathariae (disegno di C. Pesarini).

168

PARIDE DIOLI

sente in Piemonte, Trentino e in Alto Adige. A queste

citazioni posso aggiungere l’Emilia (Casola!) per un

esemplare raccolto su Nepeta catharia. Nuova segna¬

lazione per la Lombardia.

Biologia: specie infeudata su Nepeta catharia , più

raramente su Mentha spp.. Melissa spp., Lycopus spp.

89. Platyplax salviae (Schilling, 1829)

Corotipo: Europeo (EUR).

Presenza in Italia: regioni settentrionali e centrali,

sino alla Toscana e PUmbria.

Biologia: su Salvia spp.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto lungo un sentiero che dall’eremo conduce

alla Sella della Pila.

90. Plinthisus brevipennis (Latreille, 1807)

Corotipo: Turanico-Europeo-Mediterraneo (TEM).

Presenza in Italia: tutte le regioni.

Biologia: detriti di Ericacee.

91. Tropistethus fasciatus Ferrari, 1874

Corotipo: Mediterraneo (MED).

Presenza in Italia: Trentino, Veneto, Lombardia,

Emilia, Umbria, Lazio e Sicilia.

Biologia: ambienti asciutti con detriti vegetali.

92. Drymus sylvaticus (Fabricius, 1775)

Corotipo: Sibirico-Europeo-Mediterraneo (SEM).

Presenza in Italia: tutte le regioni, ma raro al Sud.

Non segnalato di Sardegna.

Biologia: detriti di latifoglie.

93. Drymus ryeii (Douglas & Scott, 1865).

Corotipo: Europeo (EUR).

Presenza in Italia: Piemonte, Valle d’Aosta, Lom¬

bardia, Veneto, Trentino e Venezia Giulia. Da confer¬

mare le segnalazioni per la Sicilia.

Biologia: detriti di latifoglie o sotto pietre.

94. Scolopostethus affinis (Schilling, 1829)

Corotipo: Sibirico-Europeo-Mediterraneo (SEM).

Presenza in Italia: tutte le regioni settentrionali e

centrali sino all’Abruzzo.

Biologia: detriti di Unica e latifoglie.

95. Scolopostethus decoratus (Flahn, 1833)

Corotipo: Europeo-Mediteraneo (EUM).

Presenza in Italia: tutte le regioni.

Biologia: detriti di Ericacee.

96. Scolopostethus cognatus (Fieber, 1861)

Corotipo: Mediteraneo (MED).

Presenza in Italia: regioni centro-meridionali e Sar¬

degna, raro però nella zona alpina dove è infeudato al¬

le zone xerotermiche o, comunque, molto soleggiate.

Biologia: Calluna vulgaris , Erica arborea.

97. Scolopostethus thomsoni Reuter, 1874

Corotipo: Olartico (OLA).

Presenza in Italia: tutte le regioni e Sardegna.

Biologia: detriti di Unica spp.

98. Taphropeltus contractus (Herrich - Schaffer, 1839)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutte le regioni, anche se piutto¬

sto raro ovunque.

Biologia: detriti di latifoglie.

99. Acompus rufipes (Wolff, 1804)

Corotipo: Sibirico-Europeo-Mediterraneo (SEM).

Presenza in Italia: tutte le regioni, tranne le isole.

Biologia: Valeriana officinalis.

100. Stygnocoris sabulosus (Schilling, 1829)

Corotipo: Olartico (OLA).

Presenza in Italia: regioni settentrionali, appenni¬

niche, Basilicata, Calabria e Sicilia.

Biologia: detriti di Artemisia spp. e Alnus spp.

101. Stygnocoris pygmaeus (Sahlberg, 1848)

Corotipo: E-Europeo (EEU).

Presenza in Italia: Trentino, Alto Adige e Lombar¬

dia.

Biologia: detriti di Ericacee, soprattutto Calluna

vulgaris.

102. Pachybrachius fracticollis (Schilling, 1829)

Corotipo: Europeo (EUR).

Presenza in Italia: regioni settentrionali sino all’E¬

milia; dubbie le citazioni per il Sud.

Biologia: Carex spp., Scirpus spp., Verbascum spp.

103. Beosus maritimus (Scopoli, 1763)

Corotipo: Turanico-Europeo-Mediterraneo (TEM).

Presenza in Italia: tutte le regioni.

Biologia: detriti di ericacee e poacee.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto in un prato vicino a Camporeso.

104. Aellopus atratus (Goeze, 1778)

Corotipo: Turanico-Europeo-Mediterraneo (TEM).

Presenza in Italia: tutte le regioni.

Biologia: su Echium spp.

105. Rhyparochromus quadratus (Fabricius, 1758)

Corotipo: Centroasiatico-Europeo-Mediterraneo

(CEM).

Presenza in Italia: tutte le regioni.

Biologia: detriti di Ericacee.

106. Rhyparochromus alboacuminatus (Goeze,

1778)

Corotipo: Turanico-Europeo-Mediterraneo (TEM).

Presenza in Italia: tutte le regioni.

Biologia: detriti di Poacee ed Ericacee.

Note di raccolta: l’insetto è stato raccolto in un

prato vicino a Camporeso.

107. Rhyparochromus confusus (Reuter, 1886).

Corotipo: Turanico-Europeo (TUE).

Presenza in Italia: tutte le regioni.

Biologia: detriti di Poacee.

108. Rhyparochromus vulgaris (Schilling, 1829)

Corotipo: Turanico-Europeo (TUE).

Presenza in Italia: tutte le regioni.

Biologia: detriti di Poacee.

109. Rhyparochromus phoeniceus (Rossi, 1794)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutte le regioni, tranne la Sarde¬

gna.

Biologia: detriti di latifoglie e Poacee.

Note di raccolta: fuori dalle staz. 1-9 l’insetto è sta¬

to raccolto ai margini di un sentiero che dall’eremo

conduce alla Sella della Pila.

GLI ETEROTTERI (HETEROPTERA) DEL MONTE BARRO (ITALIA. LOMBARDIA. LECCO)

169

110. Rhyparochromus pini (Linné, 1758)

Corotipo: Asiatico-Èuropeo (ASE).

Presenza in Italia: tutte le regioni, tranne la Sardegna.

Biologia: detriti vegetali di Poacee, latifoglie e

aghifoglie.

111. Peritrechus geniculatus (Hahn, 1832)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: regioni settentrionali, Emilia,

Toscana, Lazio, Abruzzo, Campania e Sardegna.

Biologia: detriti vegetali di Poacee, Ericacee e al¬

tre latifoglie.

112. Peritrechus gracilicomis Puton, 1877

Corotipo: Turanico-Mediterraneo (TUM).

Presenza in Italia: tutte le regioni, anche se risul¬

tano dubbie le citazioni per le due isole maggiori.

Biologia: detriti di Poacee, Ericacee e altre latifoglie.

113. Paromius leptopoides (Baerenspung, 1859)

Corotipo: Mediterraneo (MED).

Presenza in Italia: tutte le regioni e la Sardegna,

tranne la catena alpina.

Biologia: detriti di Poacee.

114. Megalonotus praetextatus (Herrich - Schaffer,

1835)

Corotipo: Turanico-Europeo-Mediterraneo (TEM).

Presenza in Italia: tutte le regioni.

Biologia: detriti di piante erbacee.

115. Megalonotus antennatus (Schilling, 1829)

Corotipo: Europeo (EUR).

Presenza in Italia: regioni settentrionali, sino al-

l’Emilia.

Biologia: detriti vegetali, con preferenza di suoli

sabbiosi.

116. Megalonotus dilatatus (Herrich - Schaffer,

1835), Fig. 3

Corotipo: Europeo (EUR).

Presenza in Italia: in letteratura compaiono vec¬

chie citazioni sparse qua e là nelle regioni settentrio¬

nali e qualcuna più recente, riferita ad ambienti di

brughiera (Dioli, 1980). Segnalato anche nelle regio¬

ni meridionali (Faraci & Rizzotti, 1995), ma raro e lo¬

calizzato ovunque. Primo reperto in Lombardia.

Biologia: detriti di Sarothamnus spp. e Genista spp.

117. Emblethis verbasci (Fabricius, 1803)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: tutte le regioni

Biologia: fra i detriti di Poacee, Ericacee, felci ecc...

Pyrrhocoridae

118. Pyrrhocoris apterus (Linnè, 1758)

Corotipo: Centroasiatico-Europeo-Mediterraneo

(CEM).

Presenza in Italia: tutte le regioni

Biologia: alla base di latifoglie (Tilia spp., Betida spp.).

Coreidae

119. Enoplops scapha (Fabricius, 1794)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutte le regioni peninsulari e Si-

■ ciba ma non frequente.

Biologia: Cirsium spp., in ambienti soleggiati e

asciutti.

Fig. 3 - Megalonotus dilatatus (disegno di C. Pesarini).

120. Coreus marginatus (Linné, 1758)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: tutte le regioni, assai comune

ovunque.

Biologia: Rumex spp.

121. Syromastes rhombeus (Linné, 1767)

Corotipo: Turanico-Europeo-Mediterraneo (TEM).

Presenza in Italia: tutte le regioni.

Biologia: Euphorbia spp. e Cariofillacee ( Spergu -

laria spp.).

122. Gonocerus acuteangulatus (Goeze, 1778)

Corotipo: Turanico-Europeo (TUE).

Presenza in Italia: tutte le regioni.

Biologia: Corylus avellana. In alcune regioni è

considerato dannoso alle coltivazioni del nocciolo.

123. Spatocera laticomis (Schilling, 1829)

Corotipo: Europeo (EUR)

Presenza in Italia: regioni settentrionali alpine.

Biologia: Polygonum spp.

124. Coriomeris scabricomis (Panzer, 1809)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: Piemonte, Lombardia, Veneto,

Trentino, Marche, Toscana, Abruzzo, Lazio, Campania,

Basilicata, Calabria e Sicilia. Prevalentemente montano.

Biologia: Trifolium spp.

170

PARIDE DIOLI

125. Coriomeris denticulatus (Scopoli, 1763)

Corotipo: Sibirico-Europeo-Mediterraneo (SEM).

Presenza in Italia: tutte le regioni.

Biologia: su Poacee.

Alydidae

126. Alydus calcaratus (Linné, 1758)

Corotipo: Olartico (OLA).

Presenza in Italia: tutte le regioni del Nord e del

Sud e Sicilia.

Biologia: specie polifaga, le larve si cibano di semi

di poacee ma sono state viste anche nutrirsi di caro¬

gne o sterco. Esse sono mirmecomorfe e sono state

rinvenute spesso con formiche del gruppo « rufa », La-

sius spp. e Myrmica spp.

Note di raccolta: fuori dalle stazioni 1-9 l’insetto è

stato raccolto in un prato vicino a Camporeso.

Rhopalidae

127. Corizus hyoscyami (Linnè, 1758)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: tutte le regioni.

Biologia: Verbascum sp., Hyoscyamus niger,

Arthemisia spp., Ononis spp., Daucus carota.

128. Rhopalus maculatus (Fieber, 1837)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: quasi tutte le regioni peninsula¬

ri e la Sicilia.

Biologia: ambienti umidi, su Comarum palustre e

Cirsium palustre.

129. Rhopalus parumpunctatus Schilling, 1829

Corotipo: Sibirico-Europeo-Mediterraneo (SEM).

Presenza in Italia: tutte le regioni.

Biologia: su Artemisia , Achillea , Chrysanthemum ,

Eryngium, Verbascum, Erodium e Rumex.

130. Rhopalus conspersus (Fieber, 1837)

Corotipo: Turanico-Europeo-Mediterraneo (TEM).

Presenza in Italia: tutte le regioni.

Biologia: su Thymus , Geranium, Silene.

Note di raccolta: fuori dalle stazioni 1-9 Pinsetto è

stato raccolto nei prati sotto la Sella della Pila (m

700) e ai margini di un sentiero che dall’eremo porta

alla Sella della Pila.

131. Rhopalus subrufus (Gmelin, 1790)

Corotipo: Cosmopolita (COS).

Presenza in Italia: tutte le regioni, sino a 2.000

metri.

Biologia: su Trifolium, Salvia pratensis, Vincetoxi-

cum nigrum , Mentina, Satureja, Urtica, Geranium e Se-

necio.

Note di raccolta: fuori dalle stazioni 1-9 l’insetto è

stato raccolto ai margini di un sentiero che dall’ere¬

mo porta alla Sella della Pila.

132. Stictopleurus pictus (Fieber, 1861)

Corotipo: Centroasiatico-Mediterraneo (CAM).

Presenza in Italia: tutte le regioni, specie al Sud.

Biologia: Achillea e Artemisia.

133. Stictopleurus abutilon (Rossi, 1790)

Corotipo: Sibirico-Europeo-Mediterraneo (SEM).

Presenza in Italia: tutte le regioni.

Biologia : Artemisia, Achillea, Carlina, Chrysanthe¬

mum.

134. Stictopleurus crassicornis (Linné, 1758)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: tutte le regioni settentrionali e

centrali sino all’Abruzzo.

Biologia: Artemisia spp., Achillea spp.

Note di raccolta: fuori dalle stazioni 1-9 l’insetto è

stato raccolto ai margini di un sentiero che dall’ere¬

mo porta alla Sella della Pila e in un prato vicino a

Camporeso.

135. Stictopleurus punctatonervosus (Goeze, 1778)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: tutte le regioni.

Biologia: Cirsium, Artemisia absinthium, Erigeron.

Note di raccolta: fuori dalle stazioni 1-9 l’insetto è

stato raccolto ai margini di un sentiero che dall’ere¬

mo porta alla Sella della Pila.

Cydnidae

136. Sehirus (Tritomegas) bicolor (Linné, 1758)

Corotipo: Sibirico-Europeo-Mediterraneo (SEM).

Presenza in Italia: tutte le regioni.

Biologia: Lamium spp.

Note di raccolta: fuori dalle stazioni 1-9 l’insetto è

stato raccolto in un prato vicino a Camporeso.

137. Sehirus (Adomerus) biguttatus (Linné, 1758)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: regioni settentrionali e centrali

sino aH’Umbria.

Biologia: Calluna vulgaris.

138. Sehirus (Canthophorus) dubius (Scopoli, 1763)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutte le regioni del Nord e pe¬

ninsulari.

Biologia: Thesium spp.

Note di raccolta: fuori dalle stazioni 1-9 l’insetto è

stato raccolto nei prati sotto la Sella della Pila (m

700) e ai margini di un sentiero che dall’eremo porta

alla Sella della Pila.

139. Legnotus limbosus (Geoffroy, 1785)

Corotipo: Turanico-Europeo-Mediterraneo (TEM).

Presenza in Italia: tutte le regioni.

Biologia: Galium spp.

Note di raccolta: fuori dalle stazioni 1-9 l’insetto è

stato raccolto presso la vetta.

140. Legnotus picipes (Fallén, 1807)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutte le regioni, più raro al Sud

dove è specie montana.

Biologia: Artemisia spp.

Note di raccolta: fuori dalle stazioni 1-9 l’insetto è

stato raccolto nei prati sotto la Sella della Pila (m

700) e in un prato della Val Faè vicino alla staz. 7.

141. Thyreocoris scarabeoides (Linné, 1758)

Corotipo: Europeo-Anatolico (EUR).

Presenza in Italia: regioni centro-settentrionali,

più raro al Sud, assente nelle isole.

Biologia: Potentina spp.

Scutelleridae

142. Odontotarsus purpureolineatus (Rossi, 1790)

Corotipo: Turanico-Mediterraneo (TUM).

Presenza in Italia: tutte le regioni, raro sulle Alpi.

GLI ETEROTTERI (HETEROPTERA) DEL MONTE BARRO (ITALIA. LOMBARDIA. LECCO)

171

Biologia: Centaurea spp., Cirsium spp. e Carduus

spp.

Note di raccolta: fuori dalle stazioni 1-9 l'insetto è

stato raccolto nei prati sotto la Sella della Pila (m

700) e ai margini di un sentiero che dall’eremo porta

alla Sella della Pila.

143. Eurygaster maurus (Linné, 1758)

Corotipo: Centroasiatico-Europeo-Mediterraneo

(CEM)

Presenza in Italia: tutte le regioni.

Biologia: su poacee.

Note di raccolta: fuori dalle stazioni 1-9 l’insetto è

stato raccolto nei prati sotto la Sella della Pila (m 700).

144. Eurygaster testudinarius (Geoffroy, 1785)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: tutte le regioni, non sembra pre¬

sente sulle isole maggiori.

Biologia: Su Poacee, sino a 1.500 metri di altezza;

spesso nei luoghi umidi.

Pentatomidae

145. Graphosoma lineatum (Linné, 1758)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutte le regioni.

Biologia: su diverse Apiacee con semi in matura¬

zione.

Note di raccolta: fuori dalle stazioni 1-9 l’insetto è

stato raccolto presso la vetta e in un prato vicino a

Camporeso.

146. Podops inuncta (Fabricius, 1775)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutte le regioni italiane, più co¬

mune al Nord.

Biologia: detriti di Poacee e Ciperacee, spesso in

ambienti semi-paludosi.

147. Sciocoris cursitans (Fabricius, 1794)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutte le regioni.

Biologia: nelle praterie secche alla base di Thymus

spp., Salvia spp., Lotus spp., Calluna spp.

148. Sciocoris macrocephalus Fieber, 1852

Corotipo: Turanico-Europeo (TUE).

Presenza in Italia: tutte le regioni.

Biologia: alla base di Thymus spp., nelle praterie

xeriche, spesso lo si trova assieme a Sciocoris cursi¬

tans (F.).

149. Sciocoris homalonotus Fieber, 1852

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: regioni settentrionali e Sarde¬

gna.

Biologia: Poa spp., Bromus spp., Dactylis glome-

rata.

150. Sciocoris microphthalmus Fior, 1860

Corotipo: Europeo (EUR).

Presenza in Italia: regioni settentrionali e centrali.

Dubbia la presenza di questa specie al Sud e in Sici-

I Ha.

Biologia: sotto Ranuncolacee ( Adonis spp.) e

Scrofulariacee ( Rhinanthus spp.) che sembrano esse¬

re le sue piante ospiti.

151. Aelia acuminata (Linné, 1758)

Corotipo: Sibirico-Europeo- Mediterraneo (SEM).

Presenza in Italia: tutte le regioni.

Biologia: su Poacee, si comporta da elemento an¬

tropofilo legato alle coltivazioni di grano, orzo, sega¬

le. Quando queste ultime sono scomparse (come è

avvenuto anche sul Barro), la specie si è adattata alle

graminacee selvatiche.

Note di raccolta: fuori dalle stazioni 1-9 l'insetto è

stato raccolto in Val Faè (in un prato vicino alla staz.

7) e in un prato vicino a Camporeso.

152. Eysarcoris aeneus (Scopoli, 1763)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: tutte le regioni.

Biologia: su svariate specie di lamiacee.

153. Staria lunata (Hahn, 1835)

Corotipo: Turanico-Mediterranea (TUM).

Presenza in Italia: in tutte le regioni, ad eccetto

della Sardegna, ma sempre in ambienti soleggiati.

Biologia: su Stachys spp. e Lamium spp.

Note di raccolta: fuori dalle stazioni 1-9 l’insetto è

stato raccolto nei prati sotto la Sella d. Pila (m 700),

ai margini di un sentiero che dall’eremo porta alla

Sella della Pila e in un prato vicino a Camporeso.

154. Dryocoris (= Holcostethus Auct.) vernalis

(Wolff, 1804)

Corotipo: Asiatico - Europeo (ASE)

Presenza in Italia: tutte le regioni.

Biologia: su Verbascum spp., Centaurea spp.,

Scrophularia spp., oltre che su un numero elevato di

altre piante ospiti.

155. Dryocoris sphacelatus (Fabricius, 1794)

Corotipo: Europeo (EUR).

Presenza in Italia: regioni settentrionali, sono de¬

gne di verifica le citazioni in Letteratura relative alle

regioni a Sud delle Marche.

Biologia: specie polifaga con qualche preferenza

per il Verbasco.

Note di raccolta: fuori dalle stazioni 1-9 l’insetto è

stato raccolto nei boschi della Val Faè.

156. Carpocoris pudicus (Poda, 1761)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: in tutte le regioni italiane, tran¬

ne la Sardegna.

Biologia: su varie Asteracee.

Note di raccolta: fuori dalle stazioni 1-9 l’insetto è

stato raccolto ai margini di un sentiero che dall’ere¬

mo porta alla Sella della Pila e in un prato vicino a

Camporeso.

157. Dolycoris baccarum (Linné, 1758)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: tutte le regioni, molto comune

dal piano sino alle alte quote.

Biologia: specie polifaga su svariate latifoglie.

Note di raccolta: fuori dalle stazioni 1-9 l’insetto è

stato raccolto nel sottobosco della Val Faè e ai margi¬

ni di un sentiero che dall’eremo porta alla Sella della

Pila.

158. Eurydema omatum (Linné, 1758)

Corotipo: Centro asiatico-Europeo-Mediterraneo

(CEM).

172

PARIDE DIOLI

Presenza in Italia: tutte le regioni.

Biologia: fitofago, prevalentemente su brassicacee.

159. Eurydema ventrale Kolenati, 1846

Corotipo: Turanico-Europeo-Mediterraneo (TEM).

Presenza in Italia: tutte le regioni peninsulari e la

Sicilia.

Biologia: fitofago, prevalentemente su Brassicacee.

160. Eurydema oleraceum (Linnè, 1758)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutte le regioni.

Biologia: su Brassicacee.

Note di raccolta: fuori dalle stazioni 1-9 l’insetto è

stato raccolto in un prato della Val Faè vicino alla

staz. 7 e in un prato vicino a Camporeso.

161. Piezodorus lituratus (Fabricius, 1794)

Corotipo: Turanico-Europeo-Mediterraneo (TEM).

Presenza in Italia: tutte le regioni, al Sud è ele¬

mento montano.

Biologia: su Fabacee.

162. Palomena prasina (Linné, 1761)

Corotipo: Sibirico-Europeo-Mediterraneo (SEM).

Presenza in Italia: tutte le regioni.

Biologia: su diverse latifoglie selvatiche o coltiva¬

te, con una spiccata predilezione per Corylus spp. e

Quercus spp.

Note di raccolta: fuori dalle stazioni 1-9 l’insetto è

stato raccolto ai margini di un sentiero che damere¬

mo porta alla Sella della Pila.

163. Nezara viridula (Fabricius, 1775)

Corotipo: Afrotropicale-Indoaustrale-Mediterra-

neo (AIM).

Presenza in Italia: tutte le regioni centro-meridio¬

nali, rara nelle Alpi.

Biologia: specie polifaga, presente soprattutto su

brassicacee coltivate ed altre piante ortensi.

Note di raccolta: fuori dalle stazioni 1-9 l’insetto è sta¬

to raccolto in un prato della Val Faè vicino alla staz. 7.

164. Raphigaster nebulosa (Poda, 1761)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: tutte le regioni.

Biologia: vive a spese di larve di Crisomelidi ( Ga -

lerucella ) su latifoglie.

165. Pentatoma rufipes (Linné, 1758)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: tutte le regioni settentrionali e,

con qualche lacuna, in quelle centro meridionali.

Biologia: su Fagus spp. e Alnus spp.

166. Picromerus bidens (Linné, 1758)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: tutte le regioni.

Biologia: su latifoglie, predatore di larve di insetti

(soprattutto bruchi di Lepidotteri).

Acanthosomatidae

168. Acanthosoma haemorrhoidale (Linné, 1758)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: quasi tutte le regioni peninsula¬

ri e Sicilia.

Biologia: su svariate latifoglie, come Betula, Carpi-

nus, Corylus. E specie dannosa alle coltivazioni del

Nocciolo. In natura, nelle Prealpi, viene collegato con

il complesso vegetazionale del « Querco-Betuletum

insubricum » (Oberdorfer, 1964) (Dioli, 1993).

Plataspidae

169. Coptosoma scutellatum (Geoffroy, 1785)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: tutte le regioni, eccetto la Sar¬

degna.

Biologia: su Medicago spp.. Coronilla spp.

Note di raccolta: fuori dalle stazioni 1-9 l’insetto è

stato raccolto nei prati sotto la Sella d. Pila (m 700) e

ai margini di un sentiero che dall’eremo porta alla

Sella d. Pila.

Considerazioni conclusive

Le specie raccolte sono state raggruppate in base

ai corotipi fondamentali della fauna W-paleartica co¬

sì come enunciati da Vigna & Coll. (1992). In aggiun¬

ta viene qui considerato il corotipo «Sibirico-Euro¬

peo-Mediterraneo», identificato con la sigla (SEM).

1. Specie ad ampia distribuzione paleartica

(OLA) Olartiche . 10

(PAL) Paleartiche . 9

ÌASE) Asiatiche-Europee . 20

SIE) Sibiriche-Europee . 24

SEM) Sibiriche-Europee-Mediterranee . 12

CEM) Centroasiatiche-Europee-Mediterranee.. 4

CAE) Centroasiatiche-Europee . 2

CAM) Centroasiatiche-Mediterranee . 2

(TEM) Turaniche-Europee-Mediterranee . 21

(TUE) Turaniche-Europee . 4

(TUM) Turaniche-Mediterranee . 4

(EUM) Europee-Mediterranee . 16

TOTALE . 128

2. Specie ad ampia distribuzione in Europa

(EUR) Europee . 23

(CEU) Centroeuropee . 4

(SEU) Sud-Europee . 3

(EEU) Est-Europee . 1

TOTALE . 31

3. Specie ad ampia distribuzione mediterranea

(MED) Mediterranee . 6

(EME) E-Mediterranee . 1

TOTALE . 7

4. Specie afrotropicali e indiane presenti nel Mediter¬

raneo

(AIM) Afrotropicali-Indoaustrali-Mediterranee. 1

167. Zicrona coerulea (Linné, 1758)

Corotipo: Olartico (OLA).

Presenza in Italia: tutte le regioni, più comune in

quelle centro-meridionali; piuttosto rara sulle Alpi.

Biologia: prevalentemente su Epilobium spp. Le

larve pare abbiano costumi fitofagi, mentre gli adulti

sono predatori di altri insetti.

5. Specie cosmopolite o subcosmopolite

(CÓS) Cosmopolite . 1

6. Specie endemiche italiane

(END) . 1

TOTALE COMPLESSIVO . 169

173

GLI ETEROTTERI (HETEROPTERA) DEL MONTE BARRO (ITALIA. LOMBARDIA. LECCO)

In conclusione, la fauna degli eterotteri del Monte

Barro risulta notevolmente omogenea con una netta

predominanza di specie ad ampia distribuzione come

è visualizzato dalla Fig. 4, dove i corotipi sono stati

raggruppati per categorie sintetiche.

Tale situazione è determinata dalla presenza di

molte specie antropofile, soprattutto tra Miridae, Ly-

gaeidae e Pentatomidae, legate ai coltivi ora degra¬

dati. Gli eterotteri appartenenti a questo vasto rag¬

gruppamento sono per lo più caratteristici delle step¬

pe a graminacee dell’Europa e dell’Asia media.

Emerge qua e là qualche elemento relitto tipico

della brughiera a Calluna vulgaris , che rappresenta la

componente più preziosa e degna di maggior tutela

( Bothynotus pilosus , Megcilonotus dilatatus).

Il Monte Barro, infine, risente climaticamente di

una certa «oceanicità», tipica dei territori perilacustri

della Lombardia e del Ticino dove si va facendo stra¬

da il concetto di fauna «insubrica» (Querco-betule-

tum insubricum e Corylo-fraxinetum insubricum)

(Dioli, 1993) così diversa da quella con caratteristiche

sub-mediterranee del Veronese, dei Monti Berici e

dei Colli Euganei.

Infatti l’assenza di piante di riferimento, come YE-

rica arborea ed il Cistus salvifolius , inibisce una mag¬

gior penetrazione e diffusione delle specie mediterra¬

nee xerotermofile.

Per quanto riguarda il confronto fra le stazioni 1-9

in base alle specie che vi sono state rinvenute, utiliz¬

zando l’indice di Dice/Sorensen e applicando la cluster

analysis secondo il metodo WPGMA si sono ottenuti i

dendrogrammi di somiglianza riportati in Fig. 5 e Fig.

6: in uno di essi (fig 5) sono state prese in considera¬

zione tutte le specie raccolte nelle stazioni, nell’altro

(Fig. 6) solo quelle esclusivamente o prevalentemente

Litofaghe. I due dendrogrammi forniscono gli stessi

raggruppamenti a riprova del fatto che le specie pre¬

datrici sono sostanzialmente ininfluenti per la caratte¬

rizzazione dei biotopi. Diversamente da quanto è sta¬

to osservato nei Curculionidi la stazione 9, situata ai

margini del lago di Annone, non si stacca da tutte le al¬

tre, probabilmente per l’«inquinamento» che le deriva

dalla non irrilevante presenza di vegetazione disorga¬

nizzata. Si separa invece, in primo luogo, la stazione 6,

fisionomicamente ben caratterizzata dalla forte ten¬

denza alla ricostruzione di una foresta moderatamen¬

te termofila. Fra le rimanenti stazioni la 7 e la 8, ambe¬

due in Val Faè, occupano una posizione isolata proba¬

bilmente per via della loro esposizione fresca.

Ringraziamenti

Colgo l’occasione per ringraziare l’amico Dr. C.

Leonardi per i consigli durante la stesura del lavoro e

la revisione critica del manoscritto e l’amico Dr. C.

Pesarini per i disegni d’insieme al tratto.

r - 4

r~i - 2

L| - 5

u - 3

/

d - 9

Li - 7

^ - 8

- 6

i i - — i - 1 - 1

0.29 0.47 0.65 0.82 1.00

Fig. 5 - Dendrogramma di similarità fra le stazioni 1-9 basato su

tutte le specie di Eterotteri presenti nei campionamenti (indice di

Dice/Sorensen + WPGMA).

5

_ Z_

I - 2

7 - 9

_ I - 8

- 7

- 6

i - 1 - 1 - 1 - 1

0.26 0.45 0.63 0.82 1.00

Fig. 6 - Dendrogramma di similarità fra le stazioni 1-9 basato so¬

lo sulle specie di Eterotteri che hanno un regime dietetico del tut¬

to o in gran parte fitofago (indice di Dice/Sorensen + WPGMA).

174

PARIDE DIOLI

BIBLIOGRAFIA

Dioli P., 1980 - Eterotteri della Brughiera di Rovasenda (Pie¬

monte): Quad. sulla «Struttura delle zoocenosi terrestri» 1. La

Brughiera pedemontana. III. CNR., Programma finalizzato

«Promozione della qualità delPambiente» Serie AQ/1/1 12: 35-

56.

Dioli P., 1992 - Esame del popolamento degli eterotteri (Insecta,

Heteroptera) negli strati bassi dell’atmosfera del Delta del Po.

Boll. Mus. civ. St. Nat. Venezia ., 41: 183-205.

Dioli R, 1993 - Eterotteri insubrici ed eterotteri xerotermici nei

territori perilacustri della Lombardia e del Ticino. (Hemipte-

ra, Heteroptera). Meni. Soc. Tic. Sci. Nat., 4: 81-86.

Dioli P.. 1995 - Eterotteri del Ferrarese: 1. La Fauna terrestre.

Quad. Staz. Ecol. civ. Mus. St. nat. Ferrara , 8: 7-49.

Faraci F. & Rizzotti Vlach M., 1995 - Heteroptera. In: Minelli

A., Ruffo S. & La Posta S. (eds.), Checklist delle specie della

fauna italiana, 41. Calderini, Bologna.

Melber A., Gunther H., Rieger Ch„ 1991 - Die Wanzenfauna

des Osterreischen Neusiedlersegebietes. (Insecta, Heteropte¬

ra). Wiss. Arbeiten Bgld., Eisenstadt., 89:63-162.

Rizzotti Vlach M., 1994 - Popolamenti ad eterotteri della Val¬

policella (Veneto, Regione veronese). (Heteroptera). Mem.

Soc. ent. ital., Genova, 73: 59-152.

Servadei A., 1967. Rhynchota (Heteroptera, Homoptera Auche-

norrhyncha). Catalogo topografico e sinonimico (Fauna d’Ita¬

lia, 9). Calderini , Bologna.

Tamanini L., 1981 - Gli Eterotteri della Basilicata e della Calabria

(Italia meridionale) (Hemiptera, Heteroptera). Mem. Mus.

Civ. Stor. nat. Verona ., 3:1-164.

Tamanini L., 1982 - Gli Eterotteri dell’Alto Adige (Insecta, Hete¬

roptera). Studi trentini Sci. nat., sez.B. 59:65-194.

Vigna Taglianti A., Audisio P.A., Belfiore C., Biondi M„ Bo¬

logna M.A., Carpaneto G.M., De Biase A., De Felici S.,

Piattella E., Racheli T„ Zapparoli M. & Zoia S., 1992 -

Riflessioni di gruppo sui corotipi fondamentali della fauna W-

paleartica ed in particolare italiana. Biogeographia, 16: 159-

179.

Paride Pioli: Museo civico di Storia Naturale, Via Cortivacci 1, 23017 Morbegno (SO) - Italia

Studi geobotanici ed entomofaunistici nel Parco Regionale del Monte Barro

Memorie della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano

Volume XXVII - Fascicolo II - 1997

Carlo Pesarini

Gli Elateridi (Coleoptera Elateridae) del Monte Barro

(Italia, Lombardia, Lecco)

Riassunto - Questo lavoro contiene una lista di Elateridi presenti nell’area del Monte Barro (Lecco). Il materiale è sta¬

to raccolto quasi completamente nell'ambito di una ricerca condotta durante gli anni 1989-1992 dal Museo di Storia Natu¬

rale di Milano. Una particolare attenzione è stata rivolta a 9 stazioni prative, di cui si fornisce una breve descrizione. Com¬

plessivamente sono state individuate 27 specie di Elateridi, con una netta dominanza di elementi europei o ad ampia di¬

stribuzione.

Abstract - Click beetles (Coleoptera Elateridae) from Monte Barro (Italy, Lombardy, Lecco).

In thè present paper a list of Elateridae from thè area of Monte Barro (Lecco) is given. The material has been almost

completely collected during a research accomplished by thè Naturai History Museum of Milano in thè years 1989-1992. Ni-

ne sampling sites have been particularly investigated and shortly described.Twenty-seven species have been collected, mo-

st of which European or widely distributed in thè Palaearctic Region. The number of Mediterranean elements is unimpor-

tant, owing to thè absence of thè typical Mediterranean host plants.

Key words: Monte Barro, Elateridae, geographic distribution.

Negli anni 1989-1992 il Museo civico di Storia Na¬

turale di Milano ha condotto una ricerca entomofau-

nistica nell’area del Monte Barro (Lombardia, Lec¬

co) col contributo del Consorzio Parco. Per quanto ri¬

guarda il popolamento di Coleotteri Elateridi, le ri¬

cerche effettuate non hanno fornito un quadro fauni¬

stico particolarmente ricco, ma sicuramente significa¬

tivo, poiché se il numero di specie individuate (27)

non è particolarmente elevato, il numero di esempla¬

ri campionati è per contro cospicuo; anche se è pres¬

soché certo che l’area indagata ospiti anche altre spe¬

cie, appare indubbio che, con la presente ricerca, sia¬

no state individuate tutte le entità più diffuse e carat¬

teristiche. Dei dati qui forniti, un ristretto numero è

da riferirsi a raccolte effettuate prima dell’inizio del¬

le campagne di ricerca dal Dr. Spreafico nei dintorni

di Galbiate, quindi ai margini dell’area del Parco, o di

poco al difuori dei suoi confini.

Osservazioni sulle stazioni di raccolta

Una parte delle raccolte è stata effettuata in 9 sta¬

zioni prative (stazioni 1-9), di cui si riportano le ca¬

ratteristiche ambientali ricavate dal contributo di

Banfi, Galasso & Sassi, in questo stesso volume. Ul¬

teriori stazioni di raccolta sono state riunite, nella ta¬

bella riassuntiva (tab. 1), in una sorta di stazione cu¬

mulativa indicata con il numero 10.

Stazione 1: Località Piani di Barra, 610 m, esp. W,

interessata da scavi archeologici (Grande Edificio). E

caratterizzata da una consistente presenza di prato

falciabile che indica una attività di foraggio residua.

Stazione 2: Località Piani di Barra, 600 m, esp. W,

interessata da scavi archeologici (Edificio II). Si tratta

di una prateria in cui è stata abbandonata la gestione

a foraggio, vi è quindi presente un leggero mantello.

Stazione 3: Conca prativa a monte del Monumen¬

to dell’Alpino, 630 m, esp. W. Vi si nota la convivenza

di elementi di prateria, elementi di prato falciabile ed

elementi di disturbo marginale.

Stazione 4: Località S. Michele, pendio in prossimità

del sentiero per Pian Sciresa, 325 m, esp. E. Su una ba¬

se di Mesobromion è in pieno sviluppo il prato falciabi¬

le, che qui presenta il carattere oligo-mesotrofico.

Stazione 5: Località Pian Sciresa, 435 m, esp. NE.

È un prato arido con montarozzi residui a brughiera;

per il resto il livello di base è costituito da prateria a

Brachypodium rupestre ssp. caespitosum.

Stazione 6: Superfici prative lungo il sentiero del¬

la «Cresta occidentale», che dall’edificio dell’ex sana¬

torio sale alla vetta, 750 m, esp. S. Si tratta di una pra¬

teria con parziale affioramento roccioso, fortemente

cespugliata e in via di chiusura, con forte influsso del¬

l’elemento prenemorale (tendenza a un Quercetum

pubescenti s. 1.)

Stazione 7: Località Fornaci Villa, in prossimità del¬

l’impluvio della Val Faè, 275 m, esp. NW. È una superfi¬

cie prativa terrazzata all’interno del bosco mesofilo,

molto simile a quella della stazione 8 ma più aperta e

con qualche elemento in più di Mesobromion.

Stazione 8: Località Fornaci Villa, in prossimità

dell’impluvio della Val Faè, 305 m, esp. NW. È un pra¬

to terrazzato irregolarmente gestito e contornato da

un bosco con notevoli contrassegni mesofili.

Stazione 9: Località Ca’ di Sala, 226 m, sulla riva

settentrionale del bacino di Oggiono del Lago di An¬

none. Vi si evidenziano tre aspetti essenziali: 1) il can¬

neto, con accenni di aggruppamento a Iris pseudoa-

corus, elementi di magnocariceto e residui di bosca-

176

CARLO PESARINI

glia riparlale 2) prato umido oligotrofico ( Molinion

coeruleae ); 3) vegetazione erbacea perenne e disor¬

ganizzata al margine superiore della stazione.

Elenco delle specie raccolte

Agrypnus murinus (Linneo)

Corotipo: Olartico (OLA).

Presenza in Italia: tutta Italia e Sicilia.

Svariati esemplari raccolti in maggio e giugno nel¬

le staz. 1, 2, 3, 4, 5 e ai margini di un sentiero che dall’

eremo porta alla Sella d. Pila.

Drasterius bimaculatus (Rossi)

Corotipo: W-paleartico (WPA).

Presenza in Italia: tutta Italia e isole.

Due esemplari raccolti nella staz. 1 (19.V.1991,

lg.Leonardi e 8. VI. 1991, lg. Sassi).

Actenicerus sjaelandicus (Miiller)

Corotipo: Olartico (OLA).

Presenza in Italia: Italia settentrionale, Toscana.

Un solo esemplare raccolto nella staz. 9

(16.V.1990, lg. Sassi).

Cidnopus pilosus (Leske)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia e Sicilia.

Numerosi esemplari raccolti in maggio e giugno

nelle staz. 1, 3, 4, 5, 6, 7 e 8, e ai margini di un sentie¬

ro che porta dall’ eremo alla Sella d. Pila.

Kibunea minuta (Linneo)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutta Italia e Sicilia.

Svariati esemplari raccolti in maggio e giugno nel¬

la staz. 2, inoltre un esemplare nella staz. 4

(10. VI. 1990, lg.Sassi) e un altro nella staz. 5

(24.VI.1992, lg. Sassi).

Limonius quercus (Olivier)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutta l’Italia continentale.

Numerosissimi esemplari raccolti in tutte le sta¬

zioni (ad eccezione della staz. 9) da maggio a luglio,

con maggiore abbondanza in maggio.

Nothodes parvulus (Panzer)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia e Sardegna.

Tre esemplari raccolti nella staz. 6 (6.VII.1990, lg.

Sassi).

Athous haemorrhoidalis (Fabricius)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Pltalia continentale.

Alcuni esemplari raccolti in maggio e giugno nel¬

le staz. 2, 3, 4, 6 e 8, altri esemplari provengono dai

prati sotto Sella d. Pila, da un prato vicino a Campo¬

reso e dal sottobosco della Val Faè.

Athous vittatus (Fabricius)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia e Sicilia.

Numerosi esemplari esemplari raccolti in maggio

e giugno nelle staz. 1 e 2.

Athous flavipennis Candèze

Corotipo: Alpino.

Presenza in Italia: Piemonte, Liguria, Lombardia,

Trentino e Appennino settentrionale.

Alcuni esemplari raccolti a fine maggio ed in giu¬

gno nelle staz. 2, 3, 4 e 5 e ai margini di un sentiero

che porta dall’ eremo alla Sella della Pila.

Athous bicolor (Goeze)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Pltalia continentale ad ec¬

cezione della Calabria.

Alcuni esemplari raccolti a fine maggio e in giu¬

gno nelle staz. 2, 3, 4 e 6.

Hemicrepidius hirtus (Herbst)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutta Italia e Sicilia.

Un unico reperto (sentiero che porta dall’ eremo

alla Sella d. Pila, 6. VII. 1990, lg. Sassi).

Adrastus axillaris Erichson

Corotipo: Europeo (EUR).

Presenza in Italia: Italia settentrionale, Toscana,

Marche, Abruzzo, Basilicata.

Un solo esemplare raccolto nella staz. 2

(27. V. 1989, lg. Sassi).

Synaptus filiformis (Fabricius)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutta Italia e isole.

Numerosi esemplari raccolti in maggio nella staz. 9.

Agriotes acuminatus (Stephens)

Corotipo: Europeo (EUR).

Presenza in Italia: presente in gran parte dell’Ita¬

lia continentale.

Un unico reperto (Boschi della Val Faè, 23.V.1991,

lg. Sassi).

Agriotes brevis Candèze

Corotipo: Europeo (EUR).

Presenza in Italia: presente in tutta Pltalia conti¬

nentale.

Alcuni esemplari raccolti in maggio nelle staz. 1, 2 e 3.

Agriotes lineatus (Linneo)

Corotipo: Olartico (OLA).

Presenza in Italia: tutta Italia e isole.

Un unico reperto (staz. 9, 25.V.1990, lg. Sassi).

Agriotes litigiosus (Rossi)

Corotipo: S-Europeo (SEU).

Presenza in Italia: tutta Italia e Sicilia.

Alcuni esemplari raccolti in giugno e luglio nelle

staz. 4 e 9.

Agriotes ustulatus (Schaller)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: Italia settentrionale e centrale,

Sicilia.

Un unico reperto (staz. 4, 8.VII.1990, lg. Sassi).

Ampedus pomonae (Stephens)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Italia settentrionale, Toscana,

Puglia.

Un esemplare raccolto nella staz. 9 (16.V.1990, lg.

Leonardi).

GLI ELATERIDI (COLEOPTERA ELATERI DAE) DEL MONTE BARRO (ITALIA, LOMBARDIA, LECCO)

177

Ampedus pomorum (Herbst)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutta l’Italia continentale.

Un esemplare raccolto nella staz. 9 (25. V. 1990, lg.

Sassi).

Melanotus crassicollis (Erichson)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia e isole.

Due soli reperti (Galbiate, 30.V.1971 e

27.VII.1980, lg. Spreafico).

Melanotus punctolineatus (Pelerin)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia e Sicilia.

Alcuni esemplari raccolti in maggio e giugno nel¬

la staz. 2, 3 e 6.

Melanotus tenebrosus (Erichson)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia e isole.

Numerosi esemplari raccolti nelle staz. 2, 5 e 6 e, sul

versante meridionale, nei prati sotto Sella della Pila (m

700).

Cardiophorus gramineus (Scopoli)

Corotipo: Europeo (EUR).

Presenza in Italia: Italia settentrionale e centrale,

Puglia, Calabria.

Un esemplare raccolto a Galbiate 83.V.1970, lg.

Spreafico)

Cardiophorus rufipes (Goeze)

Corotipo: Mediterraneo-Europeo (EUM).

Presenza in Italia: tutta Italia e isole.

Un unico reperto (staz. 2, 19.V.1991, lg. Leonardi).

Dicronychus cinereus (Herbst)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia e Sicilia.

Due soli esemplari raccolti nella staz. 2 a distanza

di un anno esatto l’uno dall’altro (15.VI.1989 e

15. VI. 1990, lg. Leonardi).

Considerazioni conclusive

Più che per altre famiglie, nel caso degli Elateridi

si è potuta osservare una predominanza quantitativa

molto accentuata di alcune specie: più della metà de¬

gli esemplari raccolti appartenevano ad una specie

sola, Limonius quercus, e dei rimanenti più della

metà appartenevano alle due specie Athous vittatus

ed A. haemorrhoidalis. Per contro, ben 10 delle 27

specie rinvenute sono state raccolte in un unico

esemplare. Nettamente predominanti, nel quadro co¬

rologico, le specie europee e sibirico-europee, come si

ricava dalla tabella 2; è interessante osservare inoltre

che le specie europee sono nettamente più numerose

di quelle ad ampia distribuzione paleartica, come

emerge con maggior evidenza dalla fig. 1, dove i co-

rotipi sono stati raggruppati per categorie sintetiche.

Va però rilevato che le specie indicate come europee

in base ai corotipi cui ci si è attenuti nel presente con¬

tributo sono in molti casi presenti anche in Asia mi¬

nore, e che per esse la più opportuna definizione del

; corotipo sarebbe quella, non contemplata, di Euro-

Anatolico. Il numero di tali elementi è indicato, fra

parentesi, dopo quello globale del corotipo europeo.

Tabella 1 - Tabella riassuntiva delle specie raccolte.

Tabella 2 - Spettro corologico delle specie raccolte.

Le sigle dei corotipi fondamentali sono ricavate dal

lavoro di Vigna Taglianti et al. (1992).

Ampia distr

44,44%

SSÉtP I . 1 1 _

-

■ —

Europea

55,56%

Fig. 1 - Corotipi raggruppati per categorie sintetiche.

178

CARLO PESARINI

BIBLIOGRAFIA

Leseigneur L., 1972 - Coléoptères Elateridae de la Faune de Fran-

ce Continentale et de Corse. Suppl. Bull. mens. Soc. linn.,

Lyon, 41:1-379.

Platia G., 1994 - Fauna d’Italia XXXIII. Coleoptera Elateridae.

Ed. C.alderini, Bologna.

Vigna Taglianti A., Audisio P. A., Belfiore C., Biondi M„ Bologna

M.A., Carpaneto G.M., De Biase A., De Felici S., Piattella E.,

Racheli T., Zapparoli M. & Zoia S., 1992 - Riflessioni di grup¬

po sui corotipi fondamentali della fauna W-paleartica ed in

particolare italiana. Biogeographia, 16: 159-179.

Carlo Pesarim: Museo Civico di Storia Naturale, Sezione Botanica, Corso Venezia 55, 20121 Milano

Studi geobotanici ed entomofaunistici nel Parco Regionale del Monte Barro

Memorie della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano

Volume XXVII - Fascicolo II - 1997

Claudio Canepari

I Coccinellidi (Coleoptera Coccinellidae) del Monte Barro

(Italia, Lombardia, Lecco)

Riassunto - L’autore presenta l’elenco di 23 specie di Coccinellidi raccolti sul rilievo brianteo del Monte Barro. Le rac¬

colte si sono concentrate soprattutto in 9 stazioni prative (staz. 1-9), 8 delle quali situate all’interno del parco regionale. Di

ciascuna specie vengono forniti i dati ecologici, corologici ed il numero di esemplari raccolti. Viene rilevata la presenza di

una popolazione numerosa ed omogenea di Scymnus femoralis (Gyllenhal). Di questa specie viene ridescritta la femmina

e vengono fornite le differenze più rilevanti con le specie affini.

Abstract - Ladybird beetles (Coleoptera Coccinellidae) from Monte Barro (Italy, Lombardy, Lecco).

The author gives thè list of 23 species of Coccinellidae collected on Monte Barro Regional Park. Nine sampling sites ha-

ve been particularly investigated, eight of which are placed inside thè Regional Park. Ecological, distributional data and thè

number of specimens collected are given for every species. The presence of a conspicuous and homogeneous population of

Scymnus femoralis (Gyllenhal) is noticed. The female of that species is redescribed and thè most relevant differences with

similar species are given.

Key words: Monte Barro, Coccinellidae, geographic distribution.

Il Monte Barro è una piccola elevazione montuo¬

sa situata a sud-ovest del ramo orientale del Lago di

Como. Ha un’altezza di m 922 ed il suo territorio, per

le sue peculiarità botaniche, geografiche e storiche è

stato costituito a Parco naturale della Regione Lom¬

bardia nel 1983. 1 suoi aspetti geomorfologici, botani¬

ci e storici sono già stati illustrati da Banfi, Galasso &

Sassi in questo stesso volume.

I Coccinellidi, sono stati raccolti in varie stazioni

negli anni 1989-92, nei mesi da marzo ad ottobre. So¬

no stati esaminati più di 350 esemplari appartenenti a

23 specie, circa 1/5 della fauna italiana.

II maggior numero dei sopralluoghi è stato effet¬

tuato in 9 stazioni prative (stazioni 1-9) di cui si ri¬

portano le caratteristiche ambientali essenziali, rica¬

vate dal contributo di Banfi, Galasso & Sassi.

Stazione 1: Località Piani di Barra, 610 m, esp. W,

interessata da scavi archeologici (Grande Edificio). È

caratterizzata da una consistente presenza di prato

falciabile che indica una attività di foraggio residua.

Stazione 2: Località Piani di Barra, 600 m, esp. W,

interessata da scavi archeologici (Edificio II). Si trat¬

ta di una prateria in cui è stata abbandonata la ge¬

stione a foraggio, vi è quindi presente un leggero

mantello.

Stazione 3: Conca prativa a monte del Monumen¬

to dell’ Alpino, 630 m, esp. W. Vi si nota la convivenza

di elementi di prateria, elementi di prato falciabile ed

elementi di disturbo marginale.

Stazione 4: Località S. Michele, pendio in prossi¬

mità del sentiero per Pian Sciresa, 325 m, esp. E. Su

una base di Mesobromion è in pieno sviluppo il pra¬

to falciabile, che qui presenta il carattere oligo-meso-

trofico.

Stazione 5: Località Pian Sciresa, 435 m, esp. NE.

È un prato arido con montarozzi residui a brughiera;

per il resto il livello di base è costituito da prateria a

Brachypodium rupestre ssp. caespitosum.

Stazione 6: Superfici prative lungo il sentiero del¬

la «Cresta occidentale», che dall’edificio dell’ex sana¬

torio sale alla vetta, 750 m, esp. S. Si tratta di una pra¬

teria con parziale affioramento roccioso, fortemente

cespugliata e in via di chiusura, con forte influsso del¬

l’elemento prenemorale (tendenza a un Quercetum

pubescentis s. 1.).

Stazione 7: Località Fornaci Villa, in prossimità

dell’impluvio della Val Faè, 275 m, esp. NW. È una su¬

perficie prativa terrazzata all’interno del bosco meso¬

frio, molto simile a quella della stazione 8 ma più

aperta e con qualche elemento in più di Mesobro¬

mion.

Stazione 8: Località Fornaci Villa, in prossimità

dell’impluvio della Val Faè, 305 m, esp. NW. È un pra¬

to terrazzato irregolarmente gestito e contornato da

un bosco con notevoli contrassegni mesofili.

Stazione 9: Località Ca’ di Sala, 226 m, sulla riva

settentrionale del bacino di Oggiono del Lago di An¬

none. Vi si evidenziano tre aspetti essenziali: 1) il can¬

neto, con accenni di aggruppamento a Iris pseudoa-

corus , elementi di magnocariceto e residui di bosca¬

glia ripariale 2) prato umido oligotrofico ( Molinion

coeruleae)\ 3) vegetazione erbacea perenne e disor¬

ganizzata al margine superiore della stazione.

180

CLAUDIO CANEPARI

Elenco delle specie raccolte

La determinazione degli esemplari è stata fatta in

base ai lavori di Mader, Fiirsch, Iablokoff- Khnzorian

e per conoscenza personale.

I corotipi sono stati attribuiti secondo le indica¬

zioni di Vigna Taglianti et Al. I dati ecologici sono

tratti dal «Die Kàfer Mitteleuropas-Òkologie», Voi 2,

di K.Koch.

Scymnus (Neopullus) haemorrhoidalis (Herbst,

1797)

Stazione: 1, 10.VI.91, 1 es; 3, 23.V.91, 1 es; 9,

15.VI.90, 4 es.

Corotipo: Sibirico-Europeo (SIE).

Distribuzione in Italia: Indicato di tutta Italia

(Porta, Luigioni), Sardegna (Luigioni). Comune nel¬

l’Italia settentrionale e centrale nelle zone umide e

paludose. Più raro ed isolato al sud ove si rinvengono

esemplari con il pronoto completamente rosso. Non

conosco esemplari di Sicilia e Sardegna.

Dati ecologici: specie euritopa, prevalentemente

arboricola, afidofaga. Il suo habitat è costituito da

3raterie umide, rive di fiumi e ruscelli (soprattutto

moschetti di Salix e Alnus ), zone sabbiose e argillose;

frequenta sia il fogliame che i vegetali secchi.

Scymnus (s. str.) femoralis (Gyllenhal, 1827) Fig. lb,

2b, 3b, 4b, 5b

Stazione: 1, 23.V.91, 1 es; 30.V.91, 1 es; 2,15.VI.90,

8 es; 3, 9.V.90, 4 es.; 23.V.91, 1 es; 10.VI.91, 1 es; 4,

21. III. 90, 1 es; 10.VI.91, 2 es; 5, 16.V.90, 1 es; 6,

27.VI.89, 2 es; 6.V.90, 2 es.; 22.VI.92, 1 es; 1.VII.92, 1

es; 9, 15.VI.90, 1 es.

Corotipo: Europeo (EUR).

Distribuzione in Italia: regioni settentrionali e

centrali.

Dati ecologici: specie stenotopa, xerofila, erbicola e

arbusticola, afidofaga. Il suo habitat è costituito da ri¬

ve fluviali sabbiose, praterie aride, bordi soleggiati di

boschi; frequenta sia il fogliame che i vegetali secchi.

Note sistematiche: la validità di questo taxon è

stata messa in dubbio. Descritto da Gyllhenhal come

specie a sè, è stato successivamente messo in sinoni¬

mia con Scymnus pygmaeus (Fourcroy, 1785) (sinoni¬

mo di Se. rubromaculatus Goeze, 1777) ed infine di

Scymnus interruptus (Goeze, 1777). L’apparato geni¬

tale maschile è identico a quello di Se. interruptus ma

le due forme non convivono. Per esempio in Gran

Bretagna è presente solo Se. femoralis e Pope nella

sua monografia degli Scymnini delle Isole Britanni¬

che lo considere buona specie. Anche Fiirsch

(1967:245) lo cita come specie a sè stante. Mentre i

maschi sono facilmente classificabili per la colorazio¬

ne e l’apparato genitale, le femmine sono difficilmen¬

te distinguibili da quelle di Se. rubromaculatus . Fur-

sch indica come carattere distintivo la morfologia

delle clave antennali, strette e fusiformi in Se. rubro¬

maculatus , larghe e ad estremità ingrossata in femo¬

ralis. La presenza sul Monte Barro di una popolazio¬

ne omogenea di Se. femoralis mi ha dato l’occasione

di esaminare un certo numero di femmine apparte¬

nenti con sicurezza a tale specie e di fornire alcuni ca¬

ratteri differenziali con le altre specie di Scymnus (s.

str.) e Scymnus (Pullus) che hanno caratteristiche di

colorazione e morfolgia esterna molto simili: Scym¬

nus rubromaculatus, Scymnus ( Pullus ) auritus e

Scymnus ( Pullus ) fraxini (Figg. 1-4).

La femmine di Se. femoralis è caratterizzata da

uno stretto orlo marginale anteriore del pronoto ros¬

sastro, in Se. rubromaculatus l’orlo anteriore rossa¬

stro è generalmente più esteso e gli angoli anteriori

del pronoto sono anch’essi rossi mentre in Se. femo¬

ralis sono sempre neri. Il receptaculum seminis in Se.

femoralis ha il nodulus lievemente più allungato che

in Se. rubromaculatus. Non ho trovato differenze im¬

portanti nella larghezza della clava antennale che

sembra, al contrario di quanto affermato da Fursch,

più larga in Se. rubromaculatus. Anche la colorazione

nera dei femori in Se. femoralis non è un carattere si¬

curo poiché si trovano spesso esemplari di Se. rubro¬

maculatus , specialmente femmine, con femori medi e

posteriori anneriti. Scymnus ( Pullus ) auritus si distin¬

gue facilmente per avere gli ultimi sterniti addomina¬

li rossi, le linee metacoxali complete, la punteggiatu¬

ra del pronoto spesso indistinta, evanescente. Scym¬

nus ( Pullus ) fraxini è di dimensioni minori, forma del

corpo più stretta, punteggiatura elitrale più robusta,

macchia del pronoto della femmina molto caratteri¬

stica. La colorazione, come in tutti i Coccinellidi, può

variare, ma generalmente i caratteri sopra descritti

sono abbastanza costanti. Le differenze tra le singole

specie sono riassunte nella tabella 1.

Scymnus (s. str.) frontalis (Fabricius, 1787)

' Stazione: 1, 10.VI.91, 1 es; 2, 15.VI.89, 1 es; 2.VI.92,

1 es; 3, 9.V.90, 3 es.; 10.VI.91, 1 es; 10.X.91, 1 es; 4,

27.VI.89 1 es; 30.III.90, 1 es; 23.V.91, 3 es; 10.VI.91, 4

es; 1. VII. 92, 1 es; 5, 10.VI.91, 1 es.; 6, 27.VI.89, 4 es;

1. VII. 92, 1 es ; 9, 15.VI.90, 33 es; 20.VII.90, 1 es; altre,

16.V.90, 1 es.; 13.IX.90, 1 es.

Fig. 1-2 - Pronoto del 8 (1) e pronoto della 9 (2) di: a) Se. femo- 1

ralis\ b) Se. rubromaculatus', c) Se. auritus ; d) Se. fraxini.

I COCCINELLIDI (COLEOPTERA COCCINELLIDAE) DEL MONTE BARRO (ITALIA. LOMBARDIA. LECCO)

181

Fig. 3-4 - Receptaculum seminis (3) e linee metacoxali (4) di: a) Se.

femoralis\ b) Se. rubromaculatus\ c) Se. auritus ; d) Se. fraxini.

Fig. 5 - Antenna di: a) Se. femoralis ; b) Se. rubromaculatus\ c) Se.

auritus ; d) Se. fraxini.

Corotipo: Centroasiatico-Europeo (CAE).

Distribuzione in Italia: tutta la penisola, sostituito

nelle regioni meridionali dalla forma immaculatus

Suffrian. Manca in Sicilia, Sardegna ed isole minori.

Dati ecologici: specie euritopa, xerofila, erbicola e

arbusticola, afidofaga. Il suo habitat è costituito da

praterie soleggiate e margini di boschi.

Scymnus ( s . str.) pallipediformis apetzoides Capra &

Fiirsch, 1967

Stazione: 1, 10.X.91, 1 es; 2, 15.VI.89, 1 es;

15. VI.90, 2 es; 19.V.91, 1 es; 3, 20.IX.89, 1 es; 10.X.91,

1 es; 4, 27.VI.89, 1 es; 23.V.91, 1 es; 10.VI.91, 1 es; 5,

16. V.90, 4 es; 10.VI.91, 2 es; 6, 27.VI.89, 5 es; 1.VII.92,

1 es; 8, 25.VIII.92, 1 es.

Corotipo: Turanico-Europeo (TUE).

Distribuzione in Italia: regioni settentrionali e

centrali sino al Molise ed Altipiano del Matese.

Dati ecologici: specie stenotopa, termofila (fre¬

quenta ambienti caldi e soleggiati), erbicola e arbu¬

sticola, afidofaga.

Note sistematiche: descritto dapprima come spe¬

cie a sè, è stato in seguito riconosciuto come sotto¬

specie di Se. pallipediformis dell’Asia Minore. La for¬

ma tipica ha due macchie elitrali, mentre la sottospe¬

cie apetzoides presenta una macchia per ciascuna eli¬

tra. E molto simile a Se. apetzi Muls. da cui si distin¬

gue oltre che per l’apparato genitale maschile, anche

per il colore leggermente più chiaro delle tibie.

Se. pallipediformis apetzoides popola le aree xeroter-

miche centro europee ed in Italia si rinviene assieme

a Se. apetzi che è più comune. Sul Monte Barro si tro¬

va invece soltanto Se. pallipediformis apetzoides.

Nephus (Sidis) anomus Mulsant, 1856

Stazione: 5, 24. VI. 90, 1 es.

Corotipo: Sud-Europeo (SEU).

Distribuzione in Italia: tutta la penisola ed isole

ma non comune.

Dati ecologici: specie stenotopa, termofila, afido¬

faga. Il suo habitat è costituito da praterie soleggiate

e margini di boschi; si trova su varie essenze erbacee

e nei detriti.

Stethorus punctillum (Weise, 1891)

Stazione: 9, 16.V.90, 1 es.

Corotipo: Europeo (EUR).

Distribuzione in Italia: tutta la penisola ed isole.

Dati ecologici: specie euritopa, spesso arboricola, te-

tranicofaga. Frequenta margini di boschi, parchi e giar¬

dini, rive di fiumi e torrenti, etc.; si può trovare su Pru-

nus spinosa e su varie piante erbacee, meno frequente¬

mente su Tilia, Hedera helix e nei boschi di conifere.

Platynaspis luteorubra (Goeze, 1777)

Stazione: 2, 15.VI.89, 1 es; 9.V.90, 1 es; 4, 27.VI.89,

1 es; 15.VII.91, 1 es.

Corotipo: Centroasiatico-Europeo-Mediterraneo

(CEM).

Distribuzione in Italia: tutta Italia.

Dati ecologici: specie euritopa, afidofaga. Si trova

generalmente in zone calde, umide o secche, spesso

sulle rive di fiumi o torrenti, probabilmente in asso¬

ciazione con formiche del genere Lasius. Frequenta

varie piante erbacee, arbusti, alberi ( Populus , Salix,

Platanus , ecc.) e muschi.

182

CLAUDIO CANEPARI

Tabella 1 - Caratteri differenziali fra Scymnus femoralis, Se. rubromaculatus, Se. anritus e Se. fraxini.

Coccidula rufa (Herbst, 1783)

Stazione: 9, 21. III. 90, 1 es; 6.V.90, 1 es; 9.V.90, 2 es;

19.V.90, 2 es; 16.V.90, 7 es; 25.V.90, 3 es; 15.VI.90, 4 es.

Corotipo: Sibirico-Europeo (SIE).

Distribuzione in Italia: Tutta la penisola, non se¬

gnalata di Sicilia; dubbia la presenza in Sardegna.

Dati ecologici: specie euritopa, erbicola e fitode-

triticola, afidofaga. Vive in zone paludose e soprattut¬

to nei canneti.

Coccidula scutellata (Herbst, 1783)

Stazione: 9, 21. IV. 92, 2 es.

Corotipo: Sibirico-Europeo (SIE).

Distribuzione in Italia: tutta la penisola ed isole.

Dati ecologici: specie stenotopa, paludicola, erbi¬

cola, afidofaga. Si trova su vegetali acquatici e ripico-

li, specialmente Typha e Phragmites.

Anisosticta novemdecimpunctata (Linnaeus, 1758)

Stazione: 9, 30.III.90, 2 es; 16.V.90, 2 es; 25.V.90, 2

es; 15.VI.90, 7 es.

Corotipo: Sibirico-Europeo (SIE).

Distribuzione in Italia: tutta la penisola, Sicilia;

manca in Sardegna.

Dati ecologici: specie stenotopa, paludicola, erbi¬

cola, afidofaga. Si trova su vegetali acquatici e ripico-

li ( Phragmites , Carex, Glyceria, Salix) e in detriti.

Hippodamia (s. str.) tredecimpunctata (Linnaeus,

1758)

Stazione: 9, 30.III.90, 1 es; 15.VI.90, 1 es; 10.X.90, 1

es. 21. IV. 92, 1 es.

Corotipo: Olartico (OLA).

Distribuzione in Italia: regioni settenntrionali e

centrali, Campania, Sicilia.

Dati ecologici: Specie stenotopa, erbicola, afidofa¬

ga. Si trova in ambienti umidi e paludosi, su vegetali

ripicoli (specialmente Carex, Sparganium, Phragmi¬

tes, Salix ) e in detriti.

Hippodamia (Adonia) variegata (Goeze, 1777)

Stazione: 6, 6.V.90, 1 es; altre, 30.IX.90, 1 es;

21.IV.92, les.

Corotipo: Centroasiatico-Europeo-Mediterraneo

(CEM), E-Africano.

Distribuzione in Italia: tutta Italia.

Dati ecologici: specie euritopa, erbicola ed arbori-

cola, afidofaga, comune su varie specie vegetali in zo¬

ne umide o secche, sia prative che boscate.

Aphidecta obliterata (Linnaeus, 1758)

Stazione: 3, 9.V.90, 1 es.

Corotipo: Europeo (EUR).

Distribuzione in Italia: Italia settentrionale, Tosca¬

na, Lazio, Abruzzo, Calabria.

Dati ecologici: specie euritopa, abitualmente silvi¬

cola, arboricola, afidofaga. Si trova di preferenza su

conifere dei generi Pinus e Picea.

Adalia (s. str.) bipunctata (Linnaeus, 1758)

Stazione: 4, 10.VI.90, 1 es; 9, 30.III.90, 1 es;

15.VI.90, 1 es; 6.VII.91, 2 es.

Corotipo: Paleartico (PAL), importato in Nord e

Sud America.

Distribuzione in Italia: tutta la penisola ed isole.

Dati ecologici: specie ubiquitaria, arboricola ed

erbicola, afidofaga.

Adalia (s. str.) decempunctata (Linnaeus, 1758)

Stazione: 1, 18.VI.91, 1 es; 5.X.94, 1 es; 2, 15.VI.90,

2 es; 3, 30.V.90, 1 es; 15.VI.90, 1 es; 4, 27.VI.89, 1 es;

10.VI.90, 1 es; 24.VI.90, 1 es; 5, 8.VII.90, 2 es; 6,

27.VI.89, 1 es; altre, 30.V.90, 1 es.

Corotipo: Paleartico (PAL).

Distribuzione in Italia: tutta la penisola ed isole.

Dati ecologici: specie euritopa, talora silvicola, afi¬

dofaga. Più arboricola della specie precedente, si tro¬

va in genere su noccioli, querce e salici.

Tytthaspis sedecimpunctata (Linnaeus, 1761)

Stazione: 1, 19.V.91, 5 es; 23.V.91, 1 es; 30.V.91, 1

es; 3, 10.VI.91, 1 es; 4, 10.X.90, 2 es; 5, 10.VI.91, 1 es;

9, 15. VI. 90, 1 es; 6.VII.90, 1 es; altre, 6.V.90, 1 es;

23.V.91, 1 es.

Corotipo: Centroasiatico-Europeo-Mediterraneo

(CEM)

I COCCINELLIDI (COLEOPTERA COCCINELLFDAE) DEL MONTE BARRO (ITALIA. LOMBARDIA, LECCO)

183

Distribuzione in Italia: tutta la penisola e le isole.

Dati ecologici: specie euritopa, afidofaga. Si trova

soprattutto in ambienti sabbiosi e paludosi, sulla ve¬

getazione erbacea e, talora, nei detriti.

Coccinella septempunctata Linnaeus, 1758

Stazione: 1, 30.V.91, 2 es; 2, 9.V.90, 3 es; 15.VI.90, 1

es; 3, 14. III. 90, 3 es; 9.V.90, 1 es; 4, 10.VI.90,1 es;

10.VI.91, 3 es; 5, 16.V.90, 1 es; 10.VI.90, 1 es; 6, 9.V.90,

1 es; altre, 6.V.90, 1 es; 30.V.90, 2 es; 6.VII.90, 1 es.

Corotipo: Paleartico (PAL), importato in Nord

America. Distribuzione in Italia: tutta la penisola e le

isole.

Dati ecologici: specie ubiquitaria, erbicola e arbo-

ricola, afidofaga.

Oenopia lyncea agnata (Rosenhauer, 1847)

Stazione: 4, 30.III.90, 1 es; 10.VI.90, 1 es; 8,

21.IV.92, 1 es.

Corotipo: Centroeuropeo (CEU).

Distribuzione in Italia: regioni settentrionali e zo¬

ne montuose delPItalia mediterranea ed isole.

Dati ecologici: specie stenotopa, termofila, arbori-

cola, afidofaga. Il suo habitat abituale è rappresenta¬

to da boschi soleggiati di querce; oltre che su Quercus

a foglie caduche è stata segnalata su Prunus spinosa.

Halyzia sedecimguttata (Linnaeus, 1758)

Stazione: 2, 15.VI.90, 1 es; 3, 9.V.90, 3 es; 30.V.90, 2

es; 6, 27.VI.89, 2 es; 8, 14.III.90, 3 es; altre, 9.V.90, 1 es;

21.IV.92, 1 es.

Corotipo: Sibirico-Europeo (SIE).

Distribuzione in Italia: tutta Italia, Sicilia, Sarde¬

gna

Dati ecologici: specie stenotopa, silvicola, arbori-

cola, micetofaga; si trova soprattutto su Quercus,

Corylus, Fraxinus, Alnus; più raramente su Picea, Pi-

nus, Larix.

Calvia ( Anisocalvia ) quatuordecimguttata (Lin¬

naeus, 1758)

Stazione: 3, 9.V.90, 1 es; 13.IX.90, 1 es; 8, 14.III.90,

1 es.; 9, 15. VI. 90, 1 es.

Corotipo: Olartico (OLA)

Distribuzione in Italia: Tutta Italia, Sardegna.

Sembra mancare in Sicilia.

Dati ecologici: specie euritopa, silvicola, arborico-

la, afidofaga. Si trova su cespugli ed alberi vari: Fagus,

Quercus, Betula, Alnus, Salix, Fraxinus, etc.

Propylea quatuordecimpunctata (Linnaeus, 1758)

Stazione: 1, 30.V.91, 1 es; 3, 9.V.90, 2 es; 19.V.91, 1

es; ;4. 10.VI.90, 2 es; 5, 16.V.90, 1 es; 10.VI.90, 1 es;

8. VII. 90, 2 es; 7, 9.V.90,1 es; 8, 16.V.90, 1 es; 6.VII.90,

1 es; 9, 9.V.90, 1 es; 25.V.90, 1 es; 15.VI.90, 2 es; altre.

25.IV.90, 2 es.

Corotipo: Paleartico (PAL), importata in Nord

America.

Distribuzione in Italia: tutta la penisola ed isole.

Dati ecologici: specie ubiquitaria, erbicola e arbo-

ricola, afidofaga.

Psyllobora vigintiduopunctata (Linnaeus, 1758)

Stazione: 1, 19.V.91, 1 es; 12.VII.91, 1 es; 2, 9.V.90,

3 es; 15.VI.90, 1 es; 3, 9.V.90, 4 es; 13.IX.90, 1 es; 4,

21. 111. 90. 1 es; 16.V.90, 1 es; 10.VI.90, 1 es;24.VI.90, 1

es; 27.VI.90, 1 es; 8.VII.90, 1 es; 13.IX.90, 1 es; 5,

30. 111. 90. 1 es; 16.V.90, 1 es; 13.IX.90, 1 es; 6, 6.VII.90,

1 es; 7, 16.V.90, 9 es; 8, 16.V.90, 1 es; 9, 25.V.90, 1 es;

15. VI.90, 1 es; altre, 25.IV.90, 1 es; 6.V.90, 3 es; 9.V.90,

1 es; 16.V.90, 1 es.; 30.V.90, 2 es; 21 .IV.92, 2 es.

Corotipo: Paleartico (PAL).

Distribuzione in Italia: tutta la penisola ed isole.

Dati ecologici: specie euritopa, spesso xerofila, er¬

bicola, micetofaga. Il suo habitat è rappresentato da

rive di corsi d’acqua o prati asciutti, prati semi umidi,

pendìi asciutti e caldi, argini e pendìi soleggiati, filari

di viti, cave, ambienti sabbiosi o ghiaiosi.

Subcoccinella vigintiquatuorpunctata (Linnaeus,

1758)

Stazione: 1, 23.V.91, 2 es; 10.X.91, 1 es; 2, 14.III.90,

1 es; 9.V.90, 5 es; 15.VI.90, 2 es; 19.V.91, 2 es; 3,

20.IX.89, 1 es; 4, 27.VI.90, 1 es; 20.IX.89, 1 es ;

10.VI.90, 4 es; 24.VI.90, 1 es; 23.V.91, 2 es; 5, 30.III.90,

2 es; 16.V.90, 2 es; 9, 30.III.90, 1 es; 9.V.90, 6 es;

16. V.90, 2 es; 16.V.91, 1 es; 15.VI.90, 2 es; 6.VII.90, 4

es; 7, 25.IV.90, 3 es.; altre: 16.V.90, 1 es.

Corotipo: Paleartico (PAL).

Distribuzione in Italia: tutta la penisola e isole.

Dati ecologici: specie euritopa, erbicola, fitofaga.

Si trova soprattutto in prati asciutti, campi arati,

sponde e pendìi, praterie aride. È un insetto polifago

rinvenibile su Medicago, Trifolium, Beta, e su Cario-

fillacee ( Saponaria , Silene, Lychnis, Dianthus)

Tabella 2: tabella riassuntiva delle specie raccolte. Al¬

tre stazioni *.

184

CLAUDIO CANEPARI

Considerazioni conclusive

Il quadro corologico della popolazione dei Cocci-

nellidi del Monte Barro, come si vede dalla tab.3 e

dalla fig. 6, dove i corotipi sono stati raggruppati per

categorie sintetiche, mette in evidenza una netta pre¬

dominanza di specie ad ampia diffusione, che si

estende talora a tutta la regione paleartica od olarti-

ca, mentre è del tutto assente la componente medi-

terranea. Solo un elemento, Nephus ( Sidis ) anomus

presenta una diffusione sud europea. Di questa spe¬

cie, che non figura nel catalogo del «Die Kàfer Mitte-

leuropas», mi era già noto un esemplare del Canton

Ticino; la zona prealpina costituisce quindi il suo li¬

mite di diffusione settentrionale. È di notevole inte¬

resse faunistico la popolazione di Scymnus ( s.str :) fe¬

morali in assenza della sua specie più prossima Se.

(s.str.) interruptus. Tale dato sembra avvalorare l’ipo¬

tesi che Se. femorali debba esere considerato una

buona specie o per lo meno una razza ecologica. Al¬

tro elemento interessante è Scymnus (s.str.) pallipe-

diformis apetzoides che forma una popolazione piut¬

tosto abbondante sul Monte Barro, dove non si rin¬

viene invece Se. (s.str.) apetzi che è la specie di Scym¬

nus più comune nell’Italia mediterranea. Popolazioni

abbondanti di Se. pallipediformis apetzoides sembra¬

no esistere anche nel Canton ticino, infatti ho esami¬

nato numerosi esemplari di questa specie raccolti a

Chiasso. Si ha dunque l’impressione che Se. pallipe¬

diformis apetzoides sia particolarmente frequente

nelle zone calde e soleggiate delle Prealpi.

Tabella 3: spettro corologico delle specie raccolte. Le

sigle dei corotipi fondamentali sono ricavate dal la¬

voro di Vigna Taglianti et al. (1991).

Fig. 6 - Corotipi raggruppati per categorie sistematiche.

BIBLIOGRAFIA

Audisio P., Canepari G, De Biase A., Poggi R., Ratti E. &

Zampetti M.F., 1955 - Coleoptera Polyphaga XI (Clavicornia

II). In: Minelli A., Ruffo S. & La Posta S. (eds.). Checklist del¬

le specie della fauna italiana, 57. Calderini, Bologna.

Canepari C., 1983 - Le specie italiane del gruppo dello Scymnus

frontalis Fab. con descrizione di due nuove specie (Coleopte¬

ra Coccinellidae). Giorn. it. Ent., 1(4): 179-204, 28.

Della Beffa G., 1913 - Revisione dei Coccinellidi Italiani. Parte

prima: Epilachninae - Coccinellinae. Ditta Verderi e C., Borgo

S. Donnino-Salsomaggiore.

Fursch H., 1959 - Scymnus interruptus Gze. forma coloris dieck-

manni nov., eine neue Aberration aus Mitteldeutschland (Col.

Cocc.). Nachricht. Bayer. Ent.. 8 (3): 28-29.

Fursch H., 1965 - Die palaearktischen Arten der Scymnus bi-

punctatus - Gruppe und die europàischen Vertreter der Un-

tergattung Sidis (Col. Cocc.). Mitt. Munck. Entom. Gesell. 55:

178-213, 85.

Fursch H., 1966 - Bemerkungen zur Systematik mitteleuropai-

scher Coccinelliden. Nachricht. Bayer. Ent. 15 (9/10): 85-90.

Fursch H., 1967 - Coccinellidae in Freude, Harde, Lohse: Die Kà¬

fer Mitteleuropas. Goecke & Evers, Krefeld, 7: 227-278, 37.

Fursch H., Kreissl E. & Capra F., 1967 - Revision einiger eu-

ropàischer Scymnus (s. str.) Arten (Col. Coccinellidae). Mitt.

Abt. Zool. Bot. Landesmuseum « Joanneum», Graz, 28: 207-259.

Gourreau J.M., 1974 - Systematique de la tribù des Scymnini

(Coccinellidae). Ann. Zool. Ecol. Anim. , Num. Hors-Ser. Paris.

Iablokoff-Khnzorian S.M., 1982 - Les Coccinelles. Coléoptères-

Coccinellidae. Soc. Nouv. Ed. Boubée, Paris.

Koch K., 1989 - Die Kàfer Mitteleuropas. Òkologie. Goecke &

Evers. Krefeld, 2: 237-253.

Luigioni P, 1929 - I Coleotteri d’Italia. Catalogo sinonimico-bi-

bliografico-topografico. Mem. Pont. Acc. Sci. Nuovi Lincei,

(II), 13: 1-1159.

Mader L., 1955 - Evidenz der palaearktischen Coccinelliden und

ihrer Aberrationen in Wort und Bilden. Ent. Arb. Mus. Gg.

Frey, Tutzing. 6(3): 764-1035.

Majerus M.E.N., 1994 - Ladybirds. Harper Collins , London.

Porta A., 1929 - Fauna Coleopterorum Italica, Stabilimento Tipo¬

grafico Piacentino, Piacenza, III: 242-277.

Vigna Taglianti A., Audisio P.A., Belfiore C., Biondi M„

Bologna M.A., Carpaneto G.M., De Biase A., De Felici

S., Piattella E., Racheli T„ Zapparoli M., Zoia S., 1992 -

Riflessioni di gruppo sui corotipi fondamentali della fauna

W-paleartica ed in particolare italiana. Biogeographia, XVI:

159-179.

Claudio Canepari: Via Venezia, 1 - 20097 San Donato Milanese

Studi geobotanici ed entomofaunistici nel Parco Regionale del Monte Barro

Memorie della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano

Volume XXVII - Fascicolo II - 1997

Carlo Pesarini & Andrea Sabbadini

I Cerambicidi (Coleoptera Cerambycidae) del Monte Barro

(Italia, Lombardia, Lecco)

Riassunto - Nel presente lavoro viene fornito un elenco delle specie di Cerambicidi rinvenuti nell’area del Monte Bar¬

ro, come risultato di una ricerca condotta negli anni 1989-1992 dal Museo di Storia Naturale di Milano. Le raccolte sono sta¬

te effettuate prevalentemente in 9 stazioni prative. Sono state rinvenute 27 specie; una di esse, Exocentrus lusitanus, risulta

nuova per la fauna lombarda. Viene infine fornita una tabella da cui possono desumersi le caratteristiche biogeografiche

della popolazione di Cerambicidi del Monte Barro.

Abstract - Long-horned beetles (Coleoptera Cerambycidae) from Monte Barro (Italy, Lombardy, Lecco).

In thè present paper are listed thè species of Cerambycidae found in thè area of Monte Barro within thè framework of

a research accomplished by thè Naturai History Museum of Milano in thè years 1989-1992. Mainly nine meadows (sampling

sites 1-9) have been investigated. Twenty-seven species have been collected; one of them, Exocentrus lusitanus , was not yet

known for thè Lombard fauna. A brief account on thè biogeograpghic pattern of thè cerambycid-fauna of Monte Barro is

finally given.

Key words: Monte Barro, Cerambycidae, geographic distribution.

Negli anni 1989-1992 il Museo Civico di Storia Na¬

turale di Milano ha condotto una ricerca entomofau-

nistica nell’area del Monte Barro (Lombardia, Lec¬

co) col contributo del Consorzio Parco. Per quanto ri¬

guarda la famiglia Cerambycidae , la quantità com¬

plessiva di materiale raccolto nel corso di questa ri¬

cerca risulta indubbiamente modesta; il numero di

specie rinvenute, peraltro, non è del tutto trascurabi¬

le, ed il quadro faunistico che ne deriva, pur se in¬

dubbiamente incompleto, è comunque significativo,

tanto da includere anche una specie che, a dispetto

della grande abbondanza di dati esistenti in letteratu¬

ra sulla famiglia, risulta nuova per la fauna lombarda.

Si è pertanto ritenuto opportuno includere anche i

Cerambicidi fra le famiglie prese in considerazione

nel presente repertorio.

Osservazioni sulle stazioni di raccolta

Una parte delle raccolte è stata effettuata in 9 sta¬

zioni prative (stazioni 1-9), di cui riportiamo le carat¬

teristiche ambientali ricavandole dal contributo di

Banfi, Galasso & Sassi, in questo stesso volume. Ul¬

teriori stazioni di raccolta sono state riunite, nella ta¬

bella riassuntiva (tab. 1), in una sorta di stazione cu¬

mulativa indicata con il numero 10.

Stazione 1; Località Piani di Barra, 610 m, esp. W,

interessata da scavi archeologici (Grande Edificio). È

caratterizzata da una consistente presenza di prato

falciabile che indica una attività di foraggio residua.

Stazione 2: Località Piani di Barra, 600 m, esp. W,

interessata da scavi archeologici (Edificio II). Si trat¬

ta di una prateria in cui è stata abbandonata la ge¬

stione a foraggio, vi è quindi presente un leggero

mantello.

Stazione 3: Conca prativa a monte del Monumen¬

to dell’Alpino, 630 m, esp. W. Vi si nota la convivenza

di elementi di prateria, elementi di prato falciabile ed

elementi di disturbo marginale.

Stazione 4: Località S. Michele, pendio in prossi¬

mità del sentiero per Pian Sciresa, 325 m, esp. E. Su

una base di Mesobromion è in pieno sviluppo il pra¬

to falciabile, che qui presenta il carattere oligo-meso-

trofico.

Stazione 5: Località Pian Sciresa, 435 m, esp. NE.

È un prato arido con montarozzi residui a brughiera;

per il resto il livello di base è costituito da prateria a

Brachypodium rupestre ssp. caespitosum.

Stazione 6: Superfici prative lungo il sentiero del¬

la “Cresta occidentale”, che dall’edificio dell’ex sana¬

torio sale alla vetta, 750 m, esp. S. Si tratta di una pra¬

teria con parziale affioramento roccioso, fortemente

cespugliata e in via di chiusura, con forte influsso del¬

l’elemento prenemorale (tendenza a un Quercetum

pubescenti s. 1.)

Stazione 7; Località Fornaci Villa, in prossimità

dell’impluvio della Val Faè, 275 m, esp. NW. È una su¬

perficie prativa terrazzata all’interno del bosco meso¬

frio, molto simile a quella della stazione 8 ma più

aperta e con qualche elemento in più di Mesobro¬

mion.

Stazione 8: Località Fornaci Villa, in prossimità

dell’impluvio della Val Faè, 305 m, esp. NW. È un pra¬

to terrazzato irregolarmente gestito e contornato da

un bosco con notevoli contrassegni mesofili.

Stazione 9: Località Ca’ di Sala, 226 m, sulla riva

settentrionale del bacino di Oggiono del Lago di An-

186

CARLO PESARINI & ANDREA SABBADINI

none. Vi si evidenziano tre aspetti essenziali: 1) il can¬

neto, con accenni di aggruppamento a Iris pseudoci-

corus , elementi di magnocariceto e residui di bosca¬

glia ripariale 2) prato umido oligotrofico ( Molinion

coeruleae)\ 3) vegetazione erbacea perenne e disor¬

ganizzata al margine superiore della stazione.

Elenco delle specie raccolte

Con l’unica eccezione costituita da un sommario

rilievo condotto in prossimità della vetta del M. Bar¬

ro, tutto il materiale è stato raccolto dal Dr. Davide

Sassi nel corso di ricerche che si sono svolte per buo¬

na parte al difuori delle stazioni di raccolta (staz. 1-9)

scelte come base per uno studio dei biotopi prativi;

per ogni specie, comunque, viene qui fornita un’indi¬

cazione sufficientemente precisa delle singole loca¬

lità di rinvenimento.

Grammoptera ruficomis (Fabricius)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia, Sicilia.

Piante ospiti: numerose latifoglie arboree e arbu-

stive.

5 esemplari raccolti fra il 9. Ili e il 30. V nelle staz.

3, 6 e 8, in un prato della Val Faè vicino alla staz. 7 e,

sul versante meridionale, ai margini di un sentiero

che dalPeremo va alla Sella della Pila.

Pseudallostema ( Pseudovadonia ) livida (Fabricius)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutta Italia, Sicilia.

Piante ospiti: numerose latifoglie (in realtà la larva

si nutre dei miceli di funghi saprofiti su radici morte).

2 esemplari raccolti nella staz. 7 (17. VII. 1992, lg.

Sassi).

Osservazioni: la specie sembrerebbe rappresenta¬

ta, in gran parte d’Italia, dalla ssp. pecta Daniel, il cui

esatto status sistematico, peraltro, necessita di revi¬

sione.

Leptura ( Rutpela ) maculata Poda

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: numerose latifoglie, più raramente

conifere.

6 esemplari raccolti nelle staz. 4, 5, e 8

(15. VII. 1991/2, lg. Sassi).

Stenurella bifasciata (Muller)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: numerose conifere e latifoglie.

3 esemplari raccolti tra P8.VII e il 2.VIII nelle

staz. 2, 3 e 4.

Stenopterus rufus (Linneo)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: numerose latifoglie.

3 esemplari raccolti in luglio nelle staz. 4, 7 e 8 e

presso la vetta.

Deilus fugax (Olivier)

Corotipo: Mediterraneo (MED).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: svariate Fabaceae della tribù Genisteae.

Un unico reperto (presso la vetta, 6. VII. 1990, lg.

Sassi).

Cerambyx scopolii (Fussly)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: numerose latifoglie.

3 esemplari raccolti nei boschi sul versante occi¬

dentale della vetta del M. Barro, 8.V.1992, lg. Sabba-

dini & Pesarini).

Phymatodes testaceus (Linneo)

Corotipo: W-Paleartico (WPA).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: numerose latifoglie.

Un unico reperto sul versante meridionale, ai mar¬

gini di un sentiero che dall’eremo conduce alla Sella

d. Pila (30. V. 1990, lg. Sassi).

Poecilium (s.str.) alni (Linneo)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia, Sicilia.

Piante ospiti: numerose latifoglie.

Un unico reperto (staz. 2, 23.V.1991, lg. Sassi).

Xylotrechus arvicola (Olivier)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: numerose latifoglie.

Un unico reperto sul versante meridionale, ai mar¬

gini di un sentiero che dall’eremo conduce alla Sella

d. Pila (6. VII. 1990, lg. Sassi).

Clytus arietis (Linneo)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutta Italia.

Piante ospiti: numerose latifoglie.

Un esemplare raccolto nella staz. 2 (24. VI. 1989)

ed uno ai margini di un sentiero che dall’eremo con¬

duce alla Sella d. Pila (30.V.1990, lg. Sassi).

Clytus rhamni Germar ssp .bellieri Gautier

Corotipo: W-Europeo (WEU).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: numerose latifoglie.

Due esemplari raccolti nella staz. 2 (12. VI. 1989 e

25. VI. 1992, lg. Sassi) ed uno nella staz. 4 (15. VII. 1991,

lg. Sassi).

Chlorophorus pilosus (Forster) ssp.glabromaculatus

(Goeze)

Corotipo: Centroeuropeo (CEU).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: numerose latifoglie.

Un unico reperto nel bosco al margine della stra¬

da asfaltata che sale verso il Monumento dell’Alpino

(6.VII.1990,lg. Sassi).

Chlorophorus varius (Muller)

Corotipo: Centroasiatico-Europeo (CAE).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: numerose latifoglie.

Alcuni esmplari raccolti in luglio e agosto nelle

staz. 2 e 9.

Chlorophorus sartor (Muller)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

I CERAMBICIDI (COLEOPTERA CERAMBYCIDAE) DEL MONTE BARRO (ITALIA. LOMBARDIA, LECCO)

187

Piante ospiti: numerose latifoglie.

Alcuni esemplari raccolti da fine giugno a inizio

agosto nelle staz. 2, 3, 4, 5 e 8, e presso la vetta.

Osservazioni: nell’ambito di questa specie, è possi¬

bile distinguere una forma orientale ed una occiden¬

tale (cui appartengono le popolazioni italiane) di¬

scretamente distinte, verosimilmente a livello sotto¬

specifico. Poiché però, come rilevato anche da Sama

(1988, p.125) non è per il momento possibile assegna¬

re alla specie una patria classica, non indicata nella

descrizione originale, la situazione nomenclatoriale

delle eventuali sottospecie non può essere attual¬

mente precisata. Sembra comunque verosimile che

alla sottospecie italiana, ove questa non andasse

identificata con la forma nominale, debba essere at¬

tribuito il nome di massiliensis (Linneo) e non quello

di infensus Plavilstshikov, come spesso indicato in let-

taratura, che ha per patria classica il Caucaso.

Parmena unifasciata (Rossi)

Corotipo: S-Europeo (SEU).

Presenza in Italia: tutta Italia.

Piante ospiti: numerose latifoglie, più di rado co¬

nifere.

Un unico reperto (staz. 3, 20.IX.1989, lg. Sassi).

Lamia textor (Linneo)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: Italia settentrionale e centrale,

Basilicata, Sicilia.

Piante ospiti: specie dei generi Salix, Populus, Be-

tula, Alnus e Morus.

Un unico reperto (staz. 6, 24.IV.1992, lg. Sassi).

Agapanthia (s.str.) cardui (Linneo)

Corotipo: W-Paleartico (WPA).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: numerose piante erbacee di svariate

famiglie.

Alcuni esemplari raccolti in maggio e giugno nel¬

le staz. 1, 2, 6 e 8.

Anaesthetis testacea (Fabricius)

Corotipo: Europeo (EUR).

Presenza in Italia: Italia settentrionale e centrale,

Campania, Calabria, Sicilia.

Piante ospiti: numerose latifoglie, ma soprattutto

querce (Quercus).

Alcuni esemplari raccolti da maggio a luglio nelle

staz. 2 e 6, in un prato sotto il Monumento all’ Alpino

e ai margini di un sentiero che dall’eremo va alla Sel¬

la d. Pila.

Exocentrus lusitanus (Linneo)

Corotipo: Europeo (EUR).

Presenza in Italia: Piemonte, Trentino- Alto Adige,

Friuli-Venezia Giulia. La specie risulta nuova per la

Lombardia.

Piante ospiti: Tilia cordata.

Un unico reperto ai margini di un sentiero che dal¬

l’eremo va alla Sella della Pila (30.V.1990, lg. Sassi).

Exocentrus adspersus Mulsant

Corotipo: Europeo (EUR).

Presenza in Italia: Italia settentrionale e centrale,

Puglia, Sicilia.

Piante ospiti: svariate specie di Fagales.

Un esemplare raccolto nella staz. 1 (12.VII.1991,

lg. Sassi), ed uno nella staz. 4 (10. VI. 1990).

Pogonochoerus hispidus (Linneo)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutta Italia, Sicilia.

Piante ospiti: numerose latifoglie.

Un unico reperto (staz. 3, 14.III.1990, lg. Sassi).

Saperda (Compsidia) populnea (Linneo)

Corotipo: Olartica (OLA).

Presenza in Italia: Italia settentrionale e centrale,

Basilicata, Calabria, Sicilia.

Piante ospiti: pioppi ( Populus ) o, più di rado, sali¬

ci (Salix).

Un unico reperto (staz. 2, 27.V.1989, lg. Sassi).

Phytoecia (s.str.) cylindrica (Linneo)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Italia settentrionale e centrale,

Campania, Puglia, Basilicata.

Piante ospiti: diverse specie di Apiaceae.

Un esemplare raccolto nella staz. 8 (16.V.1990, lg.

Sassi) e due nei boschi della Val Faè (23.V.1991, lg.

Sassi).

Phytoecia (s.str.) pustulata (Schrank)

Corotipo: Centroasiatico-Europeo (CAE).

Presenza in Italia: tutta Italia.

Piante ospiti: alcune specie di Asteraceae, ma so¬

prattutto Achillea millefolium.

Alcuni esemplari raccolti in maggio nelle staz. 1,

8 e 9.

Phytoecia (s.str.) virgula (Charpentier)

Corotipo: Centroasiatico-Europeo (CAE).

Presenza in Italia: tutta Italia, Sicilia.

Piante ospiti: svariate specie di Asteraceae.

Alcuni esemplari raccolti in maggio nella staz. 2 e

in luglio nel bosco che costeggia la strada asfaltata

che sale verso il Monumento all’Alpino.

Oberea (s.str.) linearis (Linneo)

Corotipo: Europeo (EUR).

Presenza in Italia: Italia settentrionale e centrale,

Calabria, Sicilia.

Piante ospiti: svariate latifoglie, ma soprattutto

Corylus avellana.

Un unico reperto (staz. 6, 19.V.1992).

Tabella 1 - Tabella riassuntiva delle specie raccolte.

188

CARLO PESARINI & ANDREA SABBADINI

Ripartizione delle specie in base alle categorie

corologiche

Lo spettro corologico delle specie raccolte (tabel¬

la 2) mostra una dominanza di elementi ad ampia di¬

stribuzione e una scarsissima presenza di elementi

mediterranei; lo stesso dato emerge, con maggior evi¬

denza, dalla fig.l, dove i corotipi sono stati raggrup¬

pati per categorie sintetiche.

Tabella 2 - Spettro corologico delle specie raccolte.

Le sigle dei corotipi fondamentali sono ricavate dal

lavoro di Vigna Taglianti et al. (1991).

Medit.

3.70%

Fig. 1 - Corotipi raggruppati per categorie sintetiche.

BIBLIOGRAFIA

Pesarini C. & Sabbadini A., 1995 - Insetti della Fauna Europea.

Coleotteri Cerambicidi. Natura , 85:1-132.

Sama G., 1988 - Fauna d’Italia 25. Coleoptera Cerambycidae.

Ed.Calderini , Bologna.

Vigna Taglianti A., Audisio P.A., Belfiore C., Biondi M.,

Bologna M.A., Carpaneto G.M., De Biase A., De Felici

S., Piattella E., Racheli T., Zapparoli M. & Zoia S., 1992

- Riflessioni di gruppo sui corotipi fondamentali della fauna

W-paleartica ed in particolare italiana. Biogeographia , 16:

159-179.

Villiers A., 1978 - Faune des Coléoptères de France 1. Ceramby¬

cidae. Ed. Lechevalier, Paris..

■

C arlo Pesarmi & Andrea Sabbadini: Museo Civico di Storia Naturale di Milano, Corso Venezia 55, 21121 Milano

Studi geobotanici ed entomofaunistici nel Parco Regionale del Monte Barro

Memorie della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano

Volume XXVII - Fascicolo II - 1997

Carlo Leonardi & Davide Sassi

I Crisomelidi (Coleoptera Chrysomelidae) del Monte Barro

(Italia, Lombardia, Lecco)

Riassunto - Vengono presentati i risultati di una pluriennale indagine faunistica sul rilievo brianteo del Monte Barro.

Oltre ad un elenco delle 152 specie di Crisomelidi censite (otto delle quali risultano nuove per la fauna lombarda) sono for¬

nite note biologiche per numerosi taxa e considerazioni sistematiche su alcune specie di particolare interesse: è studiata la

variabilità della lunghezza (Lp) e della larghezza (lp) del pronoto in un piccolo campione di Lilioceris merdigera del Mon¬

te Barro posto a confronto con un campione di Lilioceris schneideri raccolto in Abruzzo; sono descritte le differenze morfo¬

logiche e morfometriche fra Longitarsus minusculus e Longitarsus anacardius ; è illustrata la variabilità dell’edeago e della

silhouette elitrale in Longitarsus pinguis, per il quale si evidenzia resistenza di una forma appenninica leggermente diver¬

sa da quella alpina; è studiata la variabilità di Le, Lp, Lt, Ld in campioni del Monte Barro di Psylliodes toelgi e Ps. brisouti.

Sono raffigurati in visione ventrale e laterale gli edeagi di esemplari del Monte Barro di Longitarsus minusculus , Longitar¬

sus pinguis, Altica carinthiaca, Asiorestia crassicornis, Dibolia foersteri, Psylliodes brisouti e Psylliodes toelgi. Sono riportati

dati biologici di Cassida subreticulata e ne vengono descritte e raffigurate la larva al quinto stadio e la pupa. Le raccolte so¬

no state effettuate prevalentemente in 8 stazioni prative situate all’interno del parco regionale e selezionate in base a cri¬

teri fitosociologico-vegetazionali: la maggior parte di queste stazioni (1, 3, 4, 7 e 8) sono prati regolarmente falciati e la sta¬

zione 5 si distingue dalle rimanenti per la presenza di elementi di brughiera. Abbiamo confrontato queste stazioni co¬

struendo curve di k-dominanza, calcolando indici di diversità (i valori più bassi dell’indice di Shannon si sono ottenuti nel¬

le stazioni 3,7,8) ed effettuando infine un’analisi numerica con gli indici di Sòrensen e di Sokal-Michener per mettere in evi¬

denza il grado di affinità fra le stazioni indagate. Le raccolte sono state effettuate anche ai margini del fragmiteto che co¬

steggia il lago di Annone, in località Sala al Barro (staz. 9). Dal punto di vista zoogeografico prevalgono nei Crisomelidi le

specie ampiamente distribuite nella regione paleartica; i corotipi mediterranei costituiscono una percentuale molto piccola

(1.3%) delle specie raccolte, ma vi è un’importante presenza (18%) di elementi sudeuropei, in accordo con le caratteristi¬

che insubriche dell’area indagata. Conclude il lavoro un quadro sinottico della fenologia delle specie.

Abstract - Leaf beetles (Coleoptera Chrysomelidae) from Monte Barro (Italy, Lombardy, Lecco).

This paper is thè result of a faunistical research on thè Chrysomelid-beetles of Monte Barro Regional Park, which is pla-

ced at thè southeast end of Como Lake, in face of thè massif of thè Grigne. The authors give thè list of 152 species collected

during four years of entomological survey, with information on host plants, distributional pattern and distribution in Italy for

each taxon and biological notes for many of them. Noteworthy distributional data are reported: Longitarsus exoletus, L. fou-

drasi, L. brunneus, L. minusculus , Altica carinthiaca, Asiorestia crassicornis, Dibolia foersteri and Psylliodes brisouti are new

to Lombardia; Cryptocephalus bimaculatus is new to Calabria; Cr. flavipes in nex to Sardegna Aphthona atrovirens is new to

Molise; Longitarsus pinguis is new to Liguria, Molise and Campania; Asiorestia crassicornis is new to Emilia-Romagna; Psyl¬

liodes toelgi is new to Lazio. Systematical comments on a few species are appended, i. e.: information is given on thè variabi-

lity of pronotai length (Lp) and width (lp) in a little sample of Lilioceris merdigera from Monte Barro, which is compared

with a sample of Lilioceris schneideri from Abruzzo; morphologic and morphometric differences between Longitarsus minu¬

sculus and Longitarsus anacardius are described; in consequence of a study on thè variability of aedeagus and elytral silhouet¬

te in L. pinguis, thè existence of an Apenninic form somewhat different from thè Alpine one is emphasized; information is

given on thè variability of elytral length (Le), pronotai length (Lp), length of hind tibia (Lt) and length of prolongation of

hind tibia beyond tarsal insertion (Ld) in samples of Psylliodes brisouti and Ps. toelgi from Monte Barro. Nymph and fifth lar¬

vai instar of Cassida subreticulata are described. Aedeagi of specimens from Monte Barro belonging to following species are

figured in ventral and lateral view: Longitarsus minusculus, L. pinguis, Altica carinthiaca, Asiorestia crassicornis, Dibolia foer¬

steri, Psylliodes brisouti and Psylliodes toelgi. Most specimens have been collected in 8 sampling-sites placed inside thè Park

and selected on thè ground of physionomic-vegetational criteria. Most of these sampling-sites ( 1, 3, 4, 7 and 8) are regularly

mowed and peculiar to sampling-site 5 is thè presence of heath elements. We have compared these sampling-sites by means

of k-dominance curves, indexes of diversity (sites 3, 7 and 8 give comparatively small values of Shannon’s index) and cluster

analysis, in order to point out their degree of affinity. Also a grassland on thè border of thè swamp running along thè side of

Annone Lake, in thè district of Sala al Barro, has been investigated (site 9). From thè zoogeographic point of view species wi-

dely distributed in thè Palaearctic region are prevailing, there is a very low percentage (1.3 %) of Mediterranean elements,

but a comparatively high percentage (18 %) of south-European taxa, in agreement with thè Insubric character of thè inve¬

stigated area. A synoptic phenologic table is given in thè end of thè work.

Key words: Monte Barro, Chrysomelidae, Phenology, Geographic distribution.

Il Monte Barro è un modesto rilievo situato all’e-

stremo limite sudorientale del Triangolo Lariano, in

posizione dominante la città di Lecco e prospicente al

massiccio delle Grigne. Per il suo rilevante interesse

ambientale è attualmente un parco naturale della Re¬

gione Lombardia.

Questo studio, che presenta il risultato di quattro

anni di raccolte di coleotteri crisomelidi nell’area in

oggetto, è stato condotto secondo due direttrici. In

primo luogo si è cercato di censire tutte le specie pre¬

senti nell’intera area studiata, utilizzando le consuete

tecniche di raccolta (a vista, retino da sfalcio, ombrel-

190

CARLO LEONARDI & DAVIDE SASSI

lo entomologico). Inoltre, allo scopo di mettere in lu¬

ce eventuali caratterizzazioni faunistiche nell’ambito

delle zone prative del Parco, è stato condotto un con¬

fronto statistico del popolamento crisomelidologico

tra otto diverse stazioni, selezionate sulla base della

fisionomia della vegetazione. A causa della limitata

estensione del territorio indagato la caratterizzazione

delle stazioni è piuttosto modesta, l’analisi ha per¬

messo comunque di evidenziare alcuni aspetti signifi¬

cativi. Ad eccezione della stazione 5, che si differen¬

zia in modo evidente per la presenza dell’elemento

acidofilo di brughiera, le altre stazioni possono esse¬

re inquadrate in una tipologia di tensione tra gli ordi¬

ni non climacici Arrhenatheretalia elatioris Pawl. 1828

e Brometalia erecti Br.-Bl. 1936. Il primo ordine rap¬

presenta le comunità di prato regolarmente falciato,

di condizioni meso-eutrofiche, suolo profondo, gene¬

ralmente favorite dalla presenza di falda superficiale,

e si esprime attraverso gli elementi dell’associazione

Arrhenatheretum elatioris Br.-Bl. ex Scherr. 1925

(Arrhenatherum elatius , Tris et aria fla vescens , Dactylis

glomerata , Silene vulgaris , Ranunculus acris, Rhi-

nanthus alectorolophus, Plantago lanceolata ecc.). Il

secondo ordine, legato al dinamismo naturale ex¬

traforestale, rappresenta le comunità di prateria se¬

miarida che ricoprono suoli molto scarni o substrati

litoidi, spesso in forte pendenza, aH'inizio di una serie

dinamica che porta alla ricostruzione della copertura

forestale. La combinazione specifica ricorrente ( Bro -

mopsis erecta, Dianthus carthusianorum, Lilium bul-

biferum, Trinia glauca, Helianthemum nnmmularinm

ssp. obscurum, Sanguisorba minor ssp. mancata, Po¬

tentina neumanniana ecc .) consente di attribuire tali

espressioni all’alleanza Mesobromion erecti (Br.-Bl.

& Moor 1938) Knapp 1942. Il dinamismo naturale,

come accennato, porta in tempi brevi alla ripresa del-

Fig. 1 - Carta del Monte Barro con l’ubicazione delle stazioni 1-9.

la copertura forestale, che per tutte le stazioni si iden¬

tifica con il climax di un querceto a rovere ( Quercus

petraea ), roverella ( Q . pubescens ), orniello ( Fraxinus

ornus) e carpinello ( Ostrya carpinifolia ), inquadrabi¬

le nell’alleanza Quercion pubescenti-petreae Br.-Bl.

1932, attualmente vicariata dalle formazioni boschive

dell’ Orno- Ostryon. Al momento delle raccolte, tutte

le stazioni non più gestite presentavano un’evidente

ripresa dinamica, come si è potuto constatare dalla

costante presenza di significativi elementi dell’allean¬

za Geranion sanguinei Tx. 1961, tra cui Geranium

sanguineum, Origanum vulgare, Vincetoxicum hirun-

dinaria, Knautia drymeia ssp. centrifrons, Teucrium

chamaedrys, Thymus pulegioides ecc.

Le raccolte hanno interessato anche una piccola

superficie in località Sala al Barro, situata a ridosso

del Phragmitetum che costeggia il Lago di Annone e

denominata nel testo Stazione 9. Questa stazione non

verrà confrontata direttamente con le altre in quanto

si differenzia in modo evidente.

Caratteri stazionali specifici

Per le prime otto stazioni vengono indicate le spe¬

cie esclusive (specificità), e le tre specie più comuni

con il relativo indice di dominanza (sensu Berger &

Parker, 1970). Si tratta di un indice molto semplice

(numero di esemplari di ogni specie sul numero tota¬

le di esemplari raccolti), che però fornisce un’accet¬

tabile stima della diversità di un popolamento, tenen¬

do anche conto della buona correlazione che mostra

nei confronti del più popolare indice di Simpson. Vie¬

ne inoltre riportato l’indice di dominanza di Margalef

Dmg = (S-l)/ln(N) dove S è il numero di specie cen¬

site e N il numero totale degli individui raccolti. Per

la stazione nove, non direttamente comparabile con

le precedenti, non vengono indicate le specificità.

Stazione 1 (Fig. 67): Località Piani di Barra, 610 m,

esp. W, dal 1990 interessata da scavi archeologici in

rapporto al cosiddetto Grande Edificio. Consistente

presenza di prato falciabile che indica una attività di

foraggio residua, testimoniata anche dalla non signi¬

ficatività del mantello.

Specificità: Smaragdina aurita, Longitarsus holsa-

ticus. Dominanze: Longitarsus luridus (0,245), Poda¬

grica fuscicornis (0,179), Sphaeroderma rubidum

(0,084). 40 specie censite; 559 esemplari. Dmg = 6,16.

Stazione 2 (Fig. 67): Località Piani di Barra, 600 m, .

esp. W, dal 1990 interessata da scavi archeologici in

rapporto al cosiddetto Edificio II. Leggera prevalen¬

za di prateria e mantello su prato falciabile, cioè net¬

ta risposta all’abbandono di una gestione a foraggio

già indebolita.

Specificità: Cryptocephalus trimaculatus, Labido-

stomis tridentata, Leptinotarsa decemlineata, Lilioce-

ris lilii, Mantura obtusata, Psylliodes brisouti, Psyllio-

des ìnstabilis, Crepidodera aurea. Dominanze:

Aphthona venustula (0,122), Cryptocephalus flavipes

(0,111), Longitarsus succineus (0,092). 65 specie cen¬

site; 931 esemplari. Dmg = 9,37.

Stazione 3: Conca prativa a monte del Monumen¬

to all' Alpino, 630 m, esp. W. Convivenza di elementi

di prateria, elementi di prato falciabile ed elementi di

disturbo marginale.

Specificità: Longitarsus tabidus, Phyllotreta aerea,

Phyllotreta ochripes, Timarcha nicaeensis, Chaetocne-

I CRISOMELIDI (COLEOPTERA CHRYSOMELIDAE) DEL MONTE BARRO (ITALIA, LOMBARDIA, LECCO)

191

ma concinna, Chrysolina polita, Chrysolina rossia.

Dominanze: Longitarsus luridus (0,423), Longitarsus

succineus (0,111), Longitarsus pratensis (0,082). 56

specie censite; 2182 esemplari. Dmg = 7,15.

Stazione 4: Località S. Michele, pendio in prossi¬

mità del sentiero per Pian Sciresa, 325 m, esp. E. Su

una base di Mesobromion eredi ( Thalictrum minus,

Arabis collina) è in pieno sviluppo il prato falciabile,

che qui presenta il carattere oligo-mesotrofico.

Specificità: Chrysolina fastuosa, Chrysolina orical-

Fig. 2 - Diagrammi di saturazione delle specie censite nei periodi di raccolta.

192

CARLO LEONARDI & DAVIDE SASSI

eia, Clytra appendicina, Aphthona pygmaea, Argopus

ahrensi, Cassida subreticulata, Psylliodes cupreus,

Smaragdina flavicollis, Phyllotreta nemorum. Domi¬

nanze: Longitarsus luridus (0,182), Longitarsus exole-

tus (0,079), Longitarsus pratensis (0,069). 61 specie

censite; 1341 esemplari. Dmg = 8,33.

Stazione 5 (Fig. 67): Località Pian Sciresa, 435 m,

esp. NE. Prato arido con montarozzi residuali a bru¬

ghiera. Si caratterizza meglio di tutte le altre stazioni

per la presenza delPelemento di brughiera, accompa¬

gnato da Cytisus emeriflorus , endemismo calcicolo

SE-alpico. Per il resto il livello di base è costituito da

prateria a Brachypodium rupestre ssp. caespitosum.

Specificità: Dibolia f oersted, Crepidodera aurata,

Crytocephalus fulvus, Cryptocephalus primarius. Do¬

minanze: Aphthona herbigrada (0,116), Cryptocepha¬

lus labiatus (0,097), Cryptocephalus transiens (0,085).

46 specie censite; 941 esemplari. Dmg = 6,57.

Stazione 6 (Fig. 67): Superfici prative lungo il sen¬

tiero della «Cresta occidentale», che dall’edificio del¬

l’ex sanatorio sale alla vetta, 750 m, esp. S. Prateria con

parziale affioramento roccioso, fortemente cespuglia¬

ta e in via di chiusura. Forte influsso dell’elemento

prenemorale, con tendenza a un Quercetum pube¬

scenti s. 1. L’elemento di mantello ha scarso peso.

Specificità: Galenica pomonae, Longitarsus oblite-

ratus. Dominanze: Aphthona herbigrada (0,336),

Longitarsus helvolus (0,136), Longitarsus obliteratus

(0,086). 51 specie censite; 1678 esemplari. Dmg =

6,73.

Stazione 7 (Fig. 67): Località Fornaci Villa, in pros¬

simità dell’impluvio della Val Faè, 275 m, esp. NW. Su¬

perficie prativa terrazzata aH’interno del bosco meso¬

frio, molto simile a quella della stazione 8, ma più

aperta e con qualche elemento in più di Mesobro-

mion.

Specificità: nessuna. Dominanze: Longitarsus pra¬

tensis (0,251), Longitarsus luridus (0,214), Longitar¬

sus succineus (0,117). 32 specie censite; 426 esempla¬

ri . Dmg = 5,12.

Stazione 8 (Fig. 67): Località Fornaci Villa, in pros¬

simità dell’impluvio della Val Faè, 305 m, esp. NW. Su¬

perficie prativa terrazzata, irregolarmente gestita e

contornata da un bosco con notevoli contrassegni

mesofili. Ciò è conseguenza dell’esposizione fresca e

di un maggiore sviluppo di suolo. Sono comunque

sempre presenti gli elementi di prateria.

Specificità: Labidostomis longimana, Crypto¬

cephalus loreyi, Oomorphus concolor, Longitarsus

minusculus, Sphaeroderma testaceum. Dominanze:

Longitarsus luridus (0,274), Longitarsus pratensis

(0,224), Longitarsus salviae (0,169). 50 specie censite;

1046 esemplari. Dmg = 5,05.

Stazione 9: Località Ca’ di Sala, 226 m, sulla riva

settentrionale del bacino di Oggiono del Lago di An¬

none. Vi si evidenziano tre aspetti essenziali: 1) il can¬

neto ( Phragmitetum australi) con accenni di aggrup¬

pamento a Iris pseudoacorus, elementi di magnocari-

ceto ( Caricetum elatae) e residui di boscaglia riparia¬

te ( Salicion cinereae). 2) il prato umido oligotrofico

(Molinion coeruleae)\ 3) vegetazione erbacea peren¬

ne e disorganizzata, al margine superiore della sta¬

zione, riconducibile alle classi Artemisietea vulgaris e

Plantaginetea majoris.

Dominanze: Aphthona coerulea (0,218), Lythraria

salicariae (0,083), Asiorestia transversa (0,072). 59

specie censite; 1681 esemplari. Dmg = 7,43.

Confronto statistico delle stazioni

Le campagne di ricerca nel Parco hanno fruttato

la raccolta di 12.422 esemplari appartenenti a 152

specie, alcune di particolare interesse o inedite per la

Lombardia.

Allo scopo di valutare l’accuratezza con cui i cen¬

simenti sono stati condotti, abbiamo costruito per le

stazioni 1-8 i diagrammi di saturazione (Fig. 2), che

indicano il progressivo incremento di specie nei suc¬

cessivi periodi di raccolta. L’altezza degli istogrammi

tende ad un limite (altezza di saturazione) che corri¬

sponde al numero ideale di specie che con le tecniche

in uso è possibile censire ed è quindi indipendente

dal numero delle raccolte ulteriori. L’andamento dei

diagrammi sembra mostrare che per tutte le stazioni,

tranne 1, 7 e forse 8, si raggiungono valori molto pros-

</>

il

o Stazione 1

• Stazione 2

▲ Stazione 3

a Stazione 4

♦ Stazione 5

o Stazione 6

■ Stazione 7

□ Stazione 8

8 9 10 11 12 13

M = SA/

I ig. 3 - C onlronto tra numero medio di individui raccolti per ciascuna specie (T) e numero medio di specie censite per ogni

raccolta effettuata. Per la spiegazione vedi testo.

I CRISOMELIDI (COLEOPTERA CHRYSOMELIDAE) DEL MONTE BARRO (ITALIA, LOMBARDIA, LECCO)

193

simi all'altezza di saturazione. Riteniamo pertanto

che il quadro ottenuto dalle nostre indagini sia suffi¬

cientemente rappresentativo.

Malgrado la complessità dell’ambiente studiato

abbia impedito di effettuare raccolte quantitative, è

sembrato comunque utile ricorrere ad alcuni indici

ecologici per un confronto delle stazioni. In primo

luogo abbiamo valutato le differenze nella struttura

del popolamento delle stazioni 1-8 confrontando il

numero medio di individui raccolti per ciascuna spe¬

cie (T=I/S ) e il numero medio di specie censite per

ogni raccolta effettuata (M=S/V), dove I è il numero

di individui complessivamente raccolti nella stazione

in tutte le uscite, S è la sommatoria di tutte le specie

raccolte nella stazione nel totale delle uscite, V è il to¬

tale delle uscite effettuate nella stazione (Pesarmi,

1986). Il calcolo di tali rapporti permette di rendere

indipendenti i dati dal numero delle uscite. I valori

ottenuti sono riportati nella tabella 1 e graficamente

nella figura n. 3.

Tabella 1 - Valori di T e di M (v. testo) relativi alle sta¬

zioni 1-8.

Nel diagramma emergono alcuni raggruppamenti

quali 3; 6, caratterizzato da un elevato numero medio

di specie e di esemplari per specie, e 2; 5; 7 con carat¬

teristiche opposte. La stazione 8 presenta un alto nu¬

mero di esemplari per specie ma una bassa varietà

delle medesime, mentre il complesso 1; 4 manifesta

una tendenza contraria.

In secondo luogo abbiamo stimato la diversità e Ye-

\venness all’interno delle stazioni 1-8 utilizzando i rela-

jtivi indici di Shannon. Per valutare i confronti possibi¬

li, abbiamo determinato le curve di k-dominanza (Fig.

4), calcolando l’abbondanza relativa proporzionale

delle k specie presenti in una stazione, ed esprimendo

graficamente i risultati in forma di percentuale cumu¬

lativa. Lambshead et al. (1983) hanno infatti osservato

che, se le curve di k-dominanza si intersecano intorno

a metà del loro tragitto, il confronto degli indici di di¬

versità non può considerarsi attendibile. Nella tabella

2 sono riportati i valori (log base 2) degli indici di di¬

versità (in tondo) e di evenness (in corsivo), eviden¬

ziando i confronti possibili (+).

Tabella 2 - Valori (log base 2) degli indici di diversità

(in tondo) e di evenness (in corsivo) relativi alle sta¬

zioni 1-8. 1 confronti possibili sono indicati con +.

- Staz. 1 — ° — Staz. 2 - ■ - Staz. 3 - • - Staz. 4 - o — Staz. 5 - ♦ - Staz. 6 - * — Staz, 7 — ° Staz. 8

Fig. 4 - Curve di k-dominanza relative alle stazioni 1-8 su tutti gli anni delle raccolte.

frequenza cumulativa , frequenza cumulativa

194

CARLO LEONARDI & DAVIDE SASSI

Marzo — D - Aprile - & - Maggio — o — Giugno — «•— Luglio - Agosto - o - Settembre

Fig. 5.1 - Curve di k-dominanza relative al complesso delle stazioni 1-8 nei diversi mesi di campionamento del 1990

1 ' 1 T — I f 1 — t - 1 1 1 1 t - 1 t - 1 — i — | 1 - j 1 — |

’ 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37

numero specie raccolte

I ig ■ < urve di k-dominanza relative alla stazione 9 nei diversi mesi di campionamento del 1990.

I CRISOMELIDI (COLEOPTERA CHRYSOMELIDAE) DEL MONTE BARRO (ITALIA. LOMBARDIA, LECCO)

195

Tabella 3 - Valori (log base 2) degli indici di diversità

(in tondo) e di evenness (in corsivo) relativi ai mesi di

raccolta del 1990 nelle stazioni 1-8.

Tabella 4: valori (log base 2) degli indici di diversità

(in tondo) e di evenness relativi ai mesi di raccolta del

1990 nella stazione 9.

Dal confronto dei valori ottenuti si può affermare

che le stazioni 2, 4 e 5 costituiscono un blocco a diver¬

sità più elevata rispetto alle rimanenti, come già ap¬

pare evidente dall’andamento delle curve di k-domi-

nanza. La stazione 2 presenta anche il valore più ele¬

vato dell’indice di Margalef. Questo carattere di più

marcata «naturalità» per la stazione 2 non è probabil¬

mente dovuto ad una maggiore stabilità dell’ambien¬

te, ma ad una minore pressione antropica rispetto alle

altre aree di raccolta. Va però segnalato che negli ulti¬

mi due anni del periodo di campionamento la stazio¬

ne è stata pesantemente interessata dagli scavi ar¬

cheologici relativi al cosiddetto «Edificio 2», durante i

quali il tappeto erboso è stato completamente aspor¬

tato su una considerevole superficie. Il disturbo in ge¬

nere provocato dalle attività agricole sulla diversità

del popolamento è provato anche dai valori molto

bassi dell’indice di diversità di Shannon per le tre sta¬

zioni più intensamente sfruttate (3-7-8).

Allo scopo di evidenziare l’evoluzione stagionale

del popolamento, è stato inoltre condotto un con¬

fronto tra i diversi mesi di raccolta del 1990, anno in

cui tutte le stazioni sono state indagate con regolarità

per l’intera stagione. Anche in questo caso prima di

calcolare gli indici di Shannon abbiamo tracciato le

curve di k-dominanza, separando la stazione 9 (Fig.

5.2) dal complesso delle stazioni 1-8 (Fig. 5.1). Daì-

l’andamento dei tracciati si osserva, come prevedibi¬

le, una maggiore dominanza all'inizio della primave¬

ra e nella stagione tardo estiva-autunnale. Nelle ta¬

belle 3-4 sono riportati i valori (log base 2) degli in¬

dici di diversità (in tondo) e di evenness (in corsivo),

evidenziando i confronti possibili (+).

Con un ulteriore confronto sono state messe in

evidenza le affinità tra le stazioni 1-8 da un punto di

vista qualitativo. A questo scopo abbiamo utilizzato

l’indice di Sprensen J= C/(A+B-C) e la cluster analy-

sis secondo il metodo WPGMA, dove C sono le spe¬

cie comuni alle due stazioni messe a confronto, A le

specie esclusive della prima stazione e B le specie

esclusive della seconda stazione. I risultati vengono

presentati nel dendrogramma in Fig. 6.1 a sinistra.

Dall’analisi dei risultati si può rilevare che le stazioni

6; 5; 2, che rappresentano i prati non gestiti a foraggio,

presentano una composizione crisomelidologica si¬

mile, mentre piuttosto differente risulta il popola¬

mento dei prati 7; 8; 4, sottoposti, con maggiore o mi¬

nore regolarità, alla pratica dello sfalcio. Le stazioni 3

e 1, pure falciate ma associate al cluster dei prati na¬

turali, risentono probabilmente della vicinanza con la

stazione 2 (poche decine di metri, in linea d’aria).

L’influenza dell’azione antropica è messa ancor più

in evidenza dall’indice di Sokal Michener, (Fig.6.1 a

destra), che permette di separare in due cluster di¬

stinti i prati i prati «naturali» e quelli regolarmente

falciati.

Risultati nel complesso analoghi si ottengono con

l’analisi delle componenti principali (PCA). In parti¬

colare utilizzando soltanto le specie frequenti (alme¬

no 20 esemplari raccolti nel complesso delle stazioni)

si ottiene ancora una volta una netta separazione del

complesso 6; 5; 2 (Fig. 6.2). La prima componente

principale della variazione (asse 1, orizzontale) sem¬

brerebbe in questo caso identificabile con la tenden¬

za alla ripresa della copertura boschiva nelle stazioni

non più gestite a foraggio (varie specie legate ad es¬

senze arboree o arbustive presentano una elevata

correlazione positiva con tale componente).

Interessante risulta il confronto tra il dendro¬

gramma ottenuto con l’indice di Sprensen e quello

ottenuto utilizzando l’indice multistato «percent si-

milarity» sulla struttura del popolamento vegetale

(Banfi, Galasso e Sassi, in questo stesso volume), ri¬

portato in Fig. 7. 1 due dendrogrammi, pur presentan¬

do affinità nell’associare alcune coppie di stazioni (7-

8; 1-3; 6-5), differiscono però per una serie di elemen¬

ti, fra cui, in botanica, l’isolamento delle stazioni 6-5

rispetto alle rimanenti. Queste differenze possono es¬

sere messe in relazione con fattori biologici quali la

mobilità degli insetti e la polifagia di molte specie di

crisomelidi, che rendono in effetti improbabile una

completa sovrapposizione dei risultati.

Analisi faunistica

Viene di seguito riportato l’elenco ragionato delle

152 specie censite durante le raccolte. Ad esse posso¬

no essere aggiunti Cryptocephalus (s. str) cordiger

(Linnaeus, 1758) e Cryptocephalus (s.str.) octopuncta-

tus Scopoli che, benché non reperiti nel corso del pre¬

sente studio, furono segnalati per il monte Barro da

Buriini (1955). Per quanto riguarda il genere Astore-

asse 2

196

CARLO LEONARDI & DAVIDE SASSI

Fig. 6.1 - Dendrogrammi di similarità tra le stazioni 1-8 basati sui campionamenti dei Crisomelidi. A sinistra: indice di S0-

rensen + WPGMA. A destra: indice di Sokal-Michener + WPGMA.

• Staz. 3

• Staz. 6

• Staz. 2

• Staz. 8

Y

+

-1,5

-1

+

-0,5

-&

(I

• Staz. 1

•0,5

• Staz. 7

+

0,5

Staz. 5 •

-1.5

Staz. 4*

-2 -

asse 1

1 ig 6.2 - C ontronto delle stazioni 1-8 mediante analisi delle componenti principali.

I CRISOMELIDI (COLEOPTERA CHRY SOMELID AE) DEL MONTE BARRO (ITALIA, LOMBARDIA, LECCO)

197

l - 1 - 1 - 1 - 1

13.45 35.09 56.72 78.36 100.00

Fig. 7 - Dendrogramma di similarità tra le stazioni 1-8 basato sui

rilievi botanici (Percent similarity + WPGMA).

stia Jacob, occorre osservare che recentemente esso è

stato messo in sinonimia di Neocrepidodera Heiktgr.

(Konstantinov & Vandenberg, 1996); siamo venuti a

conoscenza di questo lavoro quando non ci era più

possibile apportare la modifica.

Plateumaris rustica (Kunze, 1818)

Corotipo: Paleartico (PAL).

Presenza in Italia: regioni settentrionali.

Piante ospiti: Cladium mariscus, Carex.

Oulema duftschmidi (Redtenbacher, 1874)

Corotipo: Turanico-Europeo-Mediterraneo (TEM).

Presenza in Italia: da definire.

Piante ospiti: Poacee coltivate e spontanee.

Crioceris duodecimpunctata duodecimpunctata

(Linnaeus, 1758)

Corotipo: Turanico-Europeo (TUE).

Presenza in Italia: tutta la Penisola, Sardegna, Sicilia.

Piante ospiti: Asparagus. Raccolta in Monte Barro

su Asparagus tenuifolius.

Lilioceris lilii lilii (Scopoli, 1763)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta la Penisola, Sardegna, Si¬

cilia.

Piante ospiti: Lilium , Fritillaria, Convallaria, Poly-

gonatum. Raccolta in Monte Barro su Lilium marta-

gon.

Lilioceris merdigera (Linnaeus, 1758)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: comune nelle regioni setten¬

trionali e centrali, molto più rara al Sud e probabil¬

mente localizzata su massicci montuosi (Ruffo, 1964).

Piante ospiti: Convallaria, Polygonatum, Lilium,

Allium. Causa danni, come la specie precedente, a li-

liacee coltivate. Raccolta in Monte Barro su Polygo¬

natum multiflorum.

Note: Berti & Rapilly (1976), nella revisione delle

specie paleartiche del genere Lilioceris indicano dif¬

ferenze morfometriche a sostegno della separazione

specifica di L. merdigera da L. schneideri Weise. In

particolare segnalano (p. 46), in un diagramma di di¬

spersione per le variabili lunghezza e larghezza del

pronoto espresse in forma logaritmica: «...malgré les

chevaulchements ... nous avons observé des zones de

dispersion bien individualisées». Su due piccoli cam¬

pioni di L. merdigera del Monte Barro (9 esemplari)

e di L. schneideri (Abruzzo, Prati di Tivo, 11 esempla¬

ri) abbiamo calcolato (in mm) i valori medi (m) e le

rispettive deviazioni standard (s) della lunghezza e

larghezza del pronoto. L. schneideri mostra effettiva¬

mente un pronoto più grande ((Lp) m = 1,88 s = 0,09;

(lp) m = 1,95 s = 0,09), contro i corrispondenti valori

di merdigera ((Lp) m = 1,74 s = 010; (lp) m = 1,85 s =

0,09). Sottoponendo i dati all’analisi della varianza

per il confronto tra medie si ottengono differenze al¬

tamente significative (F=ll,39) per le lunghezze e si¬

gnificative (F= 6,19) per le larghezze. Il rapporto

lp/Lp non sembra invece avere importanza diagnosti¬

ca, poiché il confronto tra le rette di regressione di lp

su Lp (Fig.8) mediante l’analisi della covarianza indi¬

ca una differenza non significativa (F=0,0667).

Labidistomis (s. str.) tridentata (Linnaeus, 1758)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: regioni settentrionali.

Piante ospiti: Corylus, Betula, Salix, Quercus, Spi-

raea. Prevalentemente legata allo strato arbustivo,

ma rinvenibile anche nei prati. In Monte Barro è sta¬

ta raccolta su Corylus avellana.

Labidostomis (s. str.) longimana longimana (Lin¬

naeus, 1761)

Corotipo: Turanico-Europeo (TUE).

Presenza in Italia: tutta Italia.

Piante ospiti: Fabacee dei generi Lotus e Trifo-

lium. Secondo Balachovski (1963) anche su Brassica-

cee selvatiche e cereali coltivati.

Lachnaia (s. str.) italica italica (Weise, 1882)

Corotipo: S-Europeo (SEU).

Presenza in Italia: tutta la Penisola, Sicilia.

Piante ospiti: Rubus, occasionalmente Quercus. In

Monte Barro è stata raccolta su Rubus sp.

Clytra (s. str.) quadripunctata (Linnaeus, 1758)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: tutta la Penisola.

Piante ospiti: Betula, Crataegus, Salix, Quercus,

Prunus e vari alberi da frutto. In Monte Barro spesso

raccolta su Corylus avellana.

Clytra (s. str.) appendicina Lacordaire, 1848

Corotipo: Turanico-Europeo (TUE).

Presenza in Italia: tutta la Penisola, Sicilia.

Piante ospiti: indicata in letteratura per diversi ge¬

neri (Salix, Rumex, Populus , Tamarix, Malus).

198

CARLO LEONARDI & DAVIDE SASSI

Note: la posizione sistematica di Clytra appendici-

ria è piuttosto controversa. Nella recente Checklist

della fauna italiana (Biondi et al., 1994) è considera¬

ta sottospecie di C. quadripunctata. La convivenza

delle due forme sul monte Barro sembrerebbe smen¬

tire questa interpretazione. In attesa di chiarimenti in

merito preferiamo considerare specie distinta il taxon

in questione.

Clytra (s. str.) laeviuscula (Ratzeburg, 1837)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta la Penisola, Sardegna.

Piante ospiti: Salix, Prunus , Dorycnium , Eraxinus.

In Monte Barro è stata raccolta su Salix cinerea e

Ostrya carpinifolia.

Smaragdina (s. str.) salicina (Scopoli, 1763)

Corotipo: Europeo (EUR).

Presenza in Italia: Penisola e Sicilia.

Piante ospiti: Crataegus, Salix. In Monte Barro è

molto comune anche sulla vegetazione erbacea.

Smaragdina (s. str.) flavicollis (Charpentier, 1825)

Corotipo: Europeo (EUR).

Presenza in Italia: regioni settentrionali.

Piante ospiti: Alnus glutinosa.

Note: secondo Miiller è specie moderatamente

orofila.

Smaragdina (s. str.) aurita aurita (Linnaeus, 1767)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutta la Penisola.

Piante ospiti: alberi e arbusti dei generi Corylus,

Crataegus, Betula.

Smaragdina (s. str.) affinis (Illiger, 1794)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta la Penisola.

Piante ospiti: Corylus , Quercus , Crataegus. In

Monte Barro in genere raccolta su Corylus avellana.

Coptocephala (s. str.) unifasciata unifasciata (Sco¬

poli, 1763)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: tutta la Penisola, Sicilia.

Piante ospiti: Echinophora , Pastinaca , Daucus , Fe-

rulago.

Coptocephala (s. str.) scopolina kuesteri Kraatz,

1872

Corotipo: S-Europeo (SEU).

Presenza in Italia: Penisola, Sicilia.

Piante ospiti: Apiacee dei generi Seseli e Daucus.

Pachybrachis hieroglyphicus (Laicharting, 1781)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: tutta la Penisola, Sicilia.

Piante ospiti: Salix, Populus, Betula. In Monte

Barro esclusivamente raccolta su Salix cinerea.

Note: specie igrofila. Raccolte femmine gravide

nella seconda metà di luglio.

Pachybrachis tessellatus tessellatus (Olivier, 1791)

Corotipo: S-Europeo (SEU).

Presenza in Italia: Penisola, Sicilia.

Piante ospiti: Quercus , Salix , Corylus, Erica.

Note: Specie xerofila.

Cryptocephalus (Homalopus) loreyi Solier, 1836

Corotipo: S-Europeo (SEU).

Presenza in Italia: diffuso su tutta la Penisola.

Piante ospiti: specie polifaga, legata allo strato ar-

boreo-arbustivo. Fagacee, Corilacee, Rosacee.

Cryptocephalus (Homalopus) coryli (Linnaeus, 1758)

Corotipo: Asiatico-Europeo (ASE).

165 1.7 1,75 1,8 1,85 1,9 1,95 2

lunghezza pronoto

Fig. 8 - \ ariabil ità delle dimensioni del pronoto in Lilioceris merdigera e L. schneideri (valori in millimetri).

I CRISOMELIDI (COLEOPTERA CHRY SOMELIDAE) DEL MONTE BARRO (ITALIA, LOMBARDIA, LECCO)

199

Presenza in Italia: regioni settentrionali e centrali.

Piante ospiti: specie polifaga, legata allo strato ar-

bustivo; Betulacee, Corilacee, Salicacee, Oleracee

( Fraxinus ), Rosacee. Gli esemplari furono raccolti su

Corylus avellana e Quercus pubescens.

Cryptocephalus (s. str.) primarius Harold, 1872

Corotipo: specie a gravitazione S-Europea (SEU).

Presenza in Italia: regioni settentrionali e centrali.

Piante ospiti: specie polifaga; generalmente indi¬

cata su Corilacee, Salicacee, Fagacee; Bedel (1901) la

ritiene invece legata al tappeto erboso. Da noi è stata

sempre raccolta sfalciando i prati.

Cryptocephalus (s. str.) bimaculatus Fabricius, 1781

Corotipo: Mediterraneo (MED), noto soltanto

per l’Italia, Francia meridionale e Marocco.

Presenza in Italia: regioni settentrionali e centrali,

Campania, Calabria (Sila, Cotronei: inedito).

Piante ospiti: specie polifaga, indicata su Fabacee

e Lamiacee; frequenta prevalentemente lo strato er¬

baceo e i bassi arbusti.

Note: elemento xerofilo, non molto comune.

Cryptocephalus (s. str.) trimaculatus Rossi, 1790

Corotipo: S-Europeo (SEU).

Presenza in Italia: diffuso in tutta la Penisola.

Piante ospiti: specie polifaga; Fagacee, Rosacee,

Salicacee, Anacardiacee ( Pistacia); presente anche

sul tappeto erboso.

Cryptocephalus (s. str.) bipunctatus bipunctatus

(Linnaeus, 1758)

Corotipo: Paleartico (PAL).

Presenza in Italia: diffuso in tutta la Penisola.

Piante ospiti: specie polifaga ad ampio spettro, lega¬

ta allo strato arbustivo-arboreo. Indicata su Salicacee,

Betulacee, Corilacee, Fagacee, Rosacee, Fabacee.

Note: Buriini (1955) ritiene la ab. sanguinolentus

più comune della forma tipica sul territorio italiano.

Sul Monte Barro questa variazione cromatica è inve¬

ce decisamente rara.

Cryptocephalus (s. str.) sericeus zambanellus (Mar-

seul, 1875)

Corotipo: S-Europeo (SEU).

Presenza in Italia: presente in tutta la Penisola.

Piante ospiti: specie polifaga, ma con tendenza al-

l’oligofagia; Asteracee, Ranuncolacee, Boraginacee.

Quest’ultima indicazione (Roubal, 1941) richiedereb¬

be ulteriori conferme. Raccolta prevalentemente su

Inula hirta e Geranium sanguineum.

Cryptocephalus (s. str.) transiens Franz, 1949

Corotipo: S-Europeo (SEU).

Presenza in Italia: regioni settentrionali.

Piante ospiti: specie polifaga, legata al tappeto er¬

boso. Hypericum, Ranunculus , Anthyllis , Genista,

Hieracium, Leontodon , Hypochoeris, Helichrysum,

Taraxacum , Centaurea. Accertata la frequentazione

di fiori di colore giallo, indipendentemente dalla fa¬

miglia di appartenenza. Tale comportamento è pre¬

sente anche in specie affini (C. hypochaeridis , seri-

ceus, aureolus , barii). Raccolta sul Monte Barro su di¬

verse piante, tra cui Ranunculus spp., Ruta graveo-

lens , Lotus corniculatus , Genista tinctoria.

Cryptocephalus (s. str.) nitidus (Linnaeus, 1758)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: presente in tutta la Penisola.

Piante ospiti: specie polifaga e legata allo strato

arboreo-arbustivo; Fagacee, Corilacee, Betulacee,

Rosacee. Prevalentemente raccolto su Quercus sp. e

Corylus avellana.

Cryptocephalus (s. str.) janthinus Germar, 1824

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: presente in tutta la Penisola,

Corsica e Sardegna.

Piante ospiti: legata ad ambienti umidi, polifaga

ad ampio spettro; Poacee ( Phragmites ), Betulacee, Li-

tracee, Salicacee.

Cryptocephalus (s. str.) parvulus parvulus Miiller,

1776

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: presente in tutta la Penisola,

Corsica e Sardegna.

Piante ospiti: specie polifaga, legata allo strato ar¬

bustivo-arboreo; Betulacee, Salicacee, Fagacee, Cori-

Iacee, Rosacee.

Cryptocephalus (s. str.) marginatus Fabricius, 1781

Corotipo: Europeo (EUR).

Presenza in Italia: tutta la Penisola.

Piante ospiti: essenze arbustive e arboree dei ge¬

neri Betula, Quercus, Salix, Populus, Sorbus, Rubus.

Cryptocephalus (s. str.) moraei (Linnaeus, 1758)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: diffuso in tutta la Penisola e iso¬

le maggiori.

Piante ospiti: specie oligofaga, infeudata al genere

Hypericum (Guttifere); popola il tappeto erboso.

Cryptocephalus (s. str.) flavipes Fabricius, 1781

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: diffuso in tutta la Penisola, Sici¬

lia e Sardegna (P. Conte, dato inedito).

Piante ospiti: specie polifaga ad ampio spettro,

prevalentemente legata allo strato arbustivo-arbo¬

reo; Salicacee, Betulacee, Fagacee, Corilacee, Cista-

cee. Presente anche sul tappeto erboso. Tra le essenze

frequentate sul Monte Barro furono registrati: Ostrya

carpini/ olia, Corylus avellana , Rubus sp., Geranium

sanguineum.

Note: per questa specie, essendo disponibile un nu¬

mero piuttosto elevato di esemplari raccolti, è stata

determinata la sex-ratio sui 167 individui provenienti

da quindici diversi campionamenti, distribuiti su tre

anni di raccolte in periodi compresi tra la seconda

metà di maggio e la prima metà di luglio. I risultati ri¬

velano la presenza di 67 maschi e 100 femmine, con

uno scostamento significativo dal rapporto di 1:1 per

il periodo studiato secondo il test del chi quadrato.

Cryptocephalus (s. str.) signatifrons Suffrian, 1847

Corotipo: S-Europeo (SEU).

Presenza in Italia: Penisola.

Piante ospiti: specie oligofaga, legata allo strato

arbustivo. Quercus, Corylus. Sul Monte Barro gene¬

ralmente raccolto sul nocciolo, ne è stata registrata la

presenza anche su Quercus pubescens e Ostrya carpi-

nifolia.

Cryptocephalus (s. str.) turcicus Suffrian, 1847

Corotipo: S-Europeo (SEU).

200

CARLO LEONARDI & DAVIDE SASSI

Presenza in Italia: Penisola, Sicilia, Sardegna.

Piante ospiti: specie xerofila e probabilmente oli-

gofaga. Quercus , Pistacici. Quest’ultimo dato, derivan¬

te dalle segnalazioni di vecchi Autori, meriterebbe

conferma. Generalmente raccolto sul Monte Barro

su Corylus avellana e Quercus pubescens.

Cryptocephalus ( Burlinius ) bilineatus (Linnaeus,

1767)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: regioni settentrionali e centrali.

Piante ospiti: Asteracee, Dipsacacee, Campanula-

cee. Secondo Suffrian anche su Plumbaginacee (Sta-

tice).

Cryptocephalus ( Burlinius ) elegantulus Gravenhor-

st, 1807

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: regioni settentrionali e centrali.

Piante ospiti: specie polifaga legata allo strato er¬

boso. Asteracee, Campanulacee, Geraniacee, Lamia-

cee. Elemento tendenzialmente xerofilo.

Cryptocephalus ( Burlinius ) strigosus Germar, 1823

Corotipo: S-Europeo (SEU).

Presenza in Italia: regioni peninsulari, fino alla

Campania.

Piante ospiti: specie tendenzialmente oligofaga.

Thymus , Alnus. Quest’ultimo dato, meriterebbe con¬

ferma.

Cryptocephalus ( Burlinius ) ocellatus Drapiez, 1819

Corotipo: Turanico-Europeo (TUE).

Presenza in Italia: Penisola, Sardegna, Sicilia.

Piante ospiti: segnalata su Salix, Populus , Corylus ,

Quercus , Betula , Alnus , Ulmus , Mentha, Melissa. Spe¬

cie sicuramente polifaga, e legata allo strato arboreo-

arbustivo. Le catture su essenze erbacee sono proba¬

bilmente accidentali.

Cryptocephalus ( Burlinius ) labiatus (Linnaeus,

1761)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Penisola, Sicilia.

Piante ospiti: specie polifaga ad ampio spettro,

prevalentemente legata allo strato arbustivo, ma fre¬

quentemente raccolta anche sul tappeto erboso. Be¬

tula , Alnus , Salix, Quercus , Populus , Fragaria , Vacci¬

ni um.

Note: disponendo di un numero elevato di esem¬

plari di questa specie, è stata determinata la sex-ratio

su 110 individui raccolti in 16 date di campionamen¬

to, distribuite in quattro anni. I risultati evidenziano

una fluttuazione stagionale (25 maschi e 12 femmine

nelle raccolte del periodo maggio-giugno; 33 maschi e

40 femmine nelle raccolte di luglio), con uno scosta¬

mento significativo dal rapporto di 1:1 secondo il test

del chi quadrato. La dissezione rivela peraltro che le

femmine portano uova apparentemente mature (fino

a 4-5 contemporaneamente), per tutto il periodo di

attività. Vari esemplari furono osservati in copula nel¬

la prima metà di luglio.

Cryptocephalus ( Burlinius ) vittula Suffrian, 1848

Corotipo: la posizione tassonomica nei confronti

di C- pygmaeus Fabr. è ancora da chiarire, in lavori di

sintesi recenti (Warchalowski, 1991: 280; Gruev & To-

mov, 1984: 176), il taxon è indicato come sinonimo di

C. pygmaeus , mentre Kippenberg (1994: 39) lo consi¬

dera specie distinta. Anche l’areale di distribuzione

risulta pertanto mal definito. Sembra comunque pre¬

sente in gran parte dell’Europa Meridionale, Asia

Minore, Caucaso. Il taxon presente in Nord Africa è

da sempre indicato come C. pygmaeus. Pertanto il co¬

rotipo può essere provvisoriamente indicato come S-

Europeo (SEU).

Presenza in Italia: Penisola e Sicilia.

Piante ospiti: specie oligofaga, legata al tappeto

erboso. Lamiacee dei generi Origanum , Thymus , Sa¬

tureia, Mentha.

Cryptocephalus ( Burlinius ) fulvus fulvus Goeze,

1777

Corotipo: Paleartico (PAL).

Presenza in Italia: tutte le regioni.

Piante ospiti: specie polifaga ad ampio spettro, più

frequente in genere sul tappeto erboso. Indicato in

letteratura come legato a vari generi di Corilacee, Sa-

licacee, Lamiacee, Asteracee, Fabacee, Guttifere, Ge¬

raniacee, Ericacee, Rubiacee, Apiacee ( Corylus , Po¬

pulus, Salix, Thymus, Artemisia, Achillea, Vicia, Lo¬

tus, Trifolium, Hypericum, Geranium, Calluna , Ga-

lium. Pimpinella, Laserpitium).

Cryptocephalus ( Burlinius ) pusillus Fabricius, 1777

Corotipo: Europeo (EUR).

Presenza in Italia: Penisola.

Piante ospiti: specie polifaga, legata allo strato ar¬

boreo arbustivo. Populus, Alnus, Corylus , Quercus,

Salix, Betula. Sul Monte Barro è stata raccolta esclu¬

sivamente la forma cromatica marshami Weise. Rela¬

tivamente comune all’inizio di luglio in località Pian

Sciresa (Versante Est), su Corylus avellana.

Oomorphus concolor (Sturm, 1807)

Corotipo: C-Europeo (CEU).

Presenza in Italia: regioni centro settentrionali.

Piante ospiti: Aegopodium podagraria.

Note: specie moderatamente orofila.

Eumolpus asclepiadeus (Pallas, 1773)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: regioni settentrionali e centrali.

Piante ospiti: Vincetoxicum, Cynanchum. Sul

Monte Barro la specie è strettamente legata a Vince¬

toxicum hirundinaria.

Leptinotarsa decemlineata (Say, 1824)

Corotipo: Neartico; specie importata in Europa e

rapidamente stabilizzata.

Presenza in Italia: tutta la Penisola, Sicilia.

Piante ospiti: Solanacee spontanee e coltivate. Se¬

condo Balachovski (1963) può trovarsi occasional¬

mente anche su Chenopodium, Sisimbrium, e Achil¬

lea.

Chrysolina (Euchrysolina) graminis santonici

(Contarini, 1847)

Corotipo: S-Europeo (SEU).

Presenza in Italia: Penisola.

Piante ospiti: questa specie è indicata da vari au¬

tori su Asteracee (Thanacetum, Achillea) e Lamiacee

( Lycopus , Stachys). Bourdonnè e Doguet, che la rac¬

colsero e la allevarono su Mentha aquatica e M. pule-

gium, ritengono che Achillea rappresenti solo un

ospite occasionale degli adulti. Nella stazione in cui

I CRISOMELIDI (COLEOPTERA CHRY SOMELID AE) DEL MONTE BARRO (ITALIA. LOMBARDIA, LECCO)

201

fu raccolta, la osservammo varie volte, in riposo, sulla

pagina superiore delle foglie di Phragmites australis.

Chrysolina (Erythrochrysa) polita (Linnaeus, 1758)

Corotipo: Asiatico-Europeo (ASÈ).

Presenza in Italia: tutta la Penisola, Sardegna, Si¬

cilia.

Piante ospiti: Lamiacee ( Mentha , Melissa , Lyco-

pus, Salvia , Òriganum , Nepeta , Glechoma).

Note: nel territorio studiato fu osservata la pre¬

senza di esemplari immaturi nella prima metà del

mese di ottobre.

Chrysolina (Chrysomorpha) cerealis mixta (Kue-

ster, 1844)

Corotipo: S-Europeo (SEU).

Presenza in Italia: regioni settentrionali e centrali.

Piante ospiti: indicati in letteratura diversi generi

di Lamiacee ( Thymus , Rosmarinus, Satureia , Cala-

mintha). Secondo Ruffo (1938) potrebbe essere mo-

nofaga ( Thymus serpillum ).

Chrysolina (Minchia) oricalcia (Muller, 1776)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Penisola, Sicilia.

Piante ospiti: Apiacee (. Anthriscus , Chaerophyl-

lum, Aegopodium).

Chrysolina (Colaphodes) haemoptera (Linnaeus, 1758)

Corotipo: Turanico-Europeo (TUE).

Presenza in Italia: Penisola e Sardegna, dubitati¬

vamente in Sicilia.

Piante ospiti: Plantago.

Chrysolina (Stichoptera) rossia (Illiger, 1802)

Corotipo: S-Europeo (SEU).

Presenza in Italia: tutta la Penisola.

Piante ospiti: Scrofulariacee ( Linaria ).

Chrysolina (Chalcoidea) marginata marginata

(Linnaeus, 1758)

Corotipo: Paleartico (PAL).

Presenza in Italia: regioni settentrionali.

Piante ospiti: Achillea , Artemisia , Leucanthemum.

Chrysolina (Fastuolina) fastuosa fastuosa (Scopoli,

1763)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: Penisola.

Piante ospiti: Galeopsis, Lamium. Sul Monte Bar¬

ro fu raccolta su Lamium maculatum e Galeopsis pu-

bescens.

Gastrophysa viridula (De Geer, 1775)

Corotipo: Olartico (OLA).

Presenza in Italia: regioni settentrionali.

Piante ospiti: Rumex, Polygonum , Oxyria , Rheum.

Phaedon (s. str.) cochleariae (Fabricius, 1792)

Corotipo: Paleartico (PAL).

Presenza in Italia: penisola e, dubitativamente,

Sardegna.

Piante ospiti: Brassicacee dei generi Nasturtium,

Rorippa, Armoracia , Brassica , Sinapis, ed inoltre su

; Veronica beccabunga (Scrofulariacee). Presente a

volte su Brassicacee coltivate.

Note: specie igrofila.

Hydrothassa marginella (Linnaeus, 1758)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: regioni settentrionali.

Piante ospiti: Ranuncolacee dei generi Ranuncu-

lus e Caltha.

Plagiodera versicolora (Laicharting, 1781)

Corotipo: Olartico (OLA), presente anche in In¬

dia e Taiwan (Gruev e Tomov, 1986).

Presenza in Italia: tutte le regioni.

Piante ospiti: Salix, Populus. Fu raccolta sul Mon¬

te Barro su Salix cinerea.

Chrysomela (Chrysomela) populi Linnaeus, 1758

Corotipo: Asiatico-Europeo (ASE), presente an¬

che in India (Gruev e Tomov, 1986).

Presenza in Italia: tutte le regioni.

Piante ospiti: Populus , Salix. Sul Monte Barro fu

raccolto su polloni di Populus tremula.

Timarcha (Timarcha) nicaeensis Villa, 1835

Corotipo: S-Europeo (SEU).

Presenza in Italia: regioni settentrionali.

Piante ospiti: Rubiacee del genere Galium.

Galerucella (Galerucella) nimphaeae (Linnaeus,

1758)

Corotipo: Olartico (OLA).

Presenza in Italia: Penisola.

Piante ospiti: indicati diversi generi di piante ac¬

quatiche o di luoghi umidi ( Nimphaea , Nuphar , Pota-

mogeton , Polygonum , Rumex , Sagittaria, Potentilla).

Galerucella ( Galerucella ) lineola lineola (Fabricius,

1781)

Corotipo: Paleartico (PAL).

Presenza in Italia: Penisola, Sicilia e Sardegna.

Piante ospiti: indicate in letteratura essenze arbo¬

reo arbustive ( Alnus , Salix, Corylus) ed erbacee ( Ly -

simachia e Rumex).

Galerucella (Neogalerucella) pusilla (Duftschmid,

1825)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: Penisola.

Piante ospiti: Lythrum, dubitativamente anche

Stachys, Veronica. Sul Monte Barro costantemente

raccolta su Lythrum salicaria.

Note: specie igrofila.

Galeruca (Galeruca) tanaceti (Linnaeus, 1758)

Corotipo: Paleartico (PAL), introdotta anche in N.

America secondo Gruev e Tomov (1986).

Presenza in Italia: Penisola, Sicilia.

Piante ospiti: Asteracee (Achillea, Chrysanthe-

mum ), Brassicacee ( Cardamine ), Cariofillacee ( Cera -

stium).

Note: nella prima metà di ottobre furono raccolte

femmine con uova.

Galeruca (Galeruca) pomonae (Scopoli, 1763)

Corotipo: Asiatico-Europeo (ASE), introdotta e

stabilizzata negli USA (Lopatin, 1977).

Presenza in Italia: Penisola, Sardegna, Sicilia.

Piante ospiti: Asteracee, Cariofillacee, Lamiacee,

Crucifere, Dipsacacee ( Centaurea , Scabiosa, Cirsium ,

Leontodon , Phlox, Salvia , Capsella , Knautia).

202

CARLO LEONARDI & DAVIDE SASSI

Exosoma lusitanicum (Linnaeus, 1767)

Corotipo: W-Mediterraneo (WME).

Presenza in Italia: Penisola, Sardegna, Sicilia.

Piante ospiti: Centaurea , Senecio , Vincetoxicum ,

Vitis, Cucurbitacee. Specie polifaga ad ampio spettro;

le larve rodono i bulbi di Liliacee e Amarillidacee.

Calomicrus circumfusus (Marsham, 1802)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: Penisola.

Piante ospiti: Genista , Spartium. In Monte Barro

prevalentemente su Genista tinctoria.

Luperus longicomis (Fabricius, 1781)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: regioni settentrionali.

Piante ospiti: Alnus, Corylus , Salix, Betula. Sul

Monte Barro fu osservato su Corylus avellana e Cra-

taegus sp.

Note: vari immaturi raccolti tra la seconda metà di

aprile e la prima di maggio.

Luperus flavipes (Linnaeus, 1767)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: regioni settentrionali, Toscana.

Piante ospiti: Alnus, Betula, Salix, Corylus, Ostrya.

Raccolto in Monte Barro su Quercus pubescens e

Crataegus sp.

Luperus leonardii Fogato, 1978

Corotipo: S-Europeo (SEU).

Presenza in Italia: Penisola.

Piante ospiti: Corylus, Ulmus.

Phyllotreta vittula (Redtenbacher, 1849)

Corotipo: Paleartico (PAL). La specie è presente

anche nella regione Neartica probabilmente per ef¬

fetto di importazione.

Presenza in Italia: Italia peninsulare.

Piante ospiti: Poacee, Brassicacee, occasionalmen¬

te Asteracee, Chenopodiacee e Ciperacee. L’insetto è

ampiamente diffuso negli arrenatereti e mesobrome-

ti del Monte Barro anche in assenza di brassicacee.

Phyllotreta nemorum (Linneo, 1758)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutte le regioni.

Piante ospiti: Brassicacee.

Phyllotreta striolata (Fabricius, 1801)

Corotipo: Paleartico (PAL). La specie è presente

anche nelle regioni Neartica, Afrotropicale e Orien¬

tale probabilmente per effetto di importazione.

Presenza in Italia: Italia settentrionale, Emilia-Ro¬

magna, Toscana, Lazio, Abruzzo, Campania.

Piante ospiti: Brassicacee.

Phyllotreta ochripes (Curtis, 1837)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Italia settentrionale e centrale,

Puglia, Sicilia.

Piante ospiti: Brassicacee; sul Monte Barro Alba¬

na petiolata.

Phyllotreta aerea Allard, 1859

Corotipo: Europeo-Mediterraneo (EUM). La spe¬

cie è presente anche nella regione Neartica probabil¬

mente per effetto di importazione.

Presenza in Italia: tutte le regioni.

Piante ospiti: Brassicacee, Resedacee.

Aphthona cyparissiae (Koch, 1803)

Corotipo: Europeo (EUR).

Presenza in Italia: Friuli-Venezia Giulia, Veneto,

Trentino-Alto Adige, Lombardia, Val d’Aosta,

Abruzzo.

Piante ospiti: Euforbiacee del genere Euphor-

bia.

Aphthona lutescens (Gyllenhal, 1808)

Corotipo: Turanico-Europeo (TUE)

Presenza in Italia: tutte le regioni.

Piante ospiti: Litracee, Lamiacee (?), Rosacee.

Note biologiche: A. lutescens è caratteristica di

fragmiteti, dove vive su Lythrum salicaria, o di moli-

nieti, dove vive su Filipendula ulmaria; Doguet (1994:

127) asserisce di averla trovata in numero anche su

Rubus ma sul Monte Barro l’insetto non sembra fre¬

quentare questa pianta: è comune nella palude di Ca’

di Sala e assente nelle stazioni all’interno del parco,

se si esclude un unico reperto in Val di Faè, che rite¬

niamo del tutto accidentale.

Note sistematiche: alla varietà praeclara Weise,

che occupa la parte orientale dell’areale, alcuni auto¬

ri attribuiscono valore di sottospecie.

Aphthona pygmaea pygmaea Kutschera, 1861

Corotipo: Europeo (EUR).

Presenza in Italia: tutte le regioni.

Piante ospiti: Euforbiacee del genere Euphorbia.

Note biologiche: Perner (1996: 247, 253-254) la

considera specie xerotermofila; in praterie aride (teu-

crio-seslerieti) dell’ex Germania orientale ha riscon¬

trato la presenza di individui immaturi da fine luglio

a fine agosto e di femmine con uova da aprile a giu¬

gno; secondo questo autore gli adulti sono attivi fino

all’inizio di novembre e ricompaiono in aprile dopo

aver superato l’inverno.

Note sistematiche: è generalmente ammessa resi¬

stenza di una sottospecie (orientali Mulsant & Rey)

nelle regioni sud-orientali del Mediterraneo, caratteriz¬

zata dalla notevole finezza della punteggiatura elitrale.

Aphthona venustula venustula Kutschera, 1861

Corotipo: Europeo (EUR).

Presenza in Italia: ssp. tipica: Italia settentrionale e

centrale, Campania, Basilicata, Puglia; ssp. attica Wei¬

se, 1890: Sicilia.

Piante ospiti: Euforbiacee del genere Euphorbia.

Note biologiche: sul Monte Barro i maschi, molto

comuni in maggio, sembrano diventare più rari rispet¬

to alle femmine nel mese successivo. Abbiamo rileva¬

to la presenza di femmine con uova in giugno e un ma¬

schio non del tutto maturo è stato raccolto alla fine di

agosto. Secondo Perner (1996: 254, 257) gli adulti, in

praterie aride dell’ex Germania orientale, sono attivi

da aprile (dopo lo svernamento) all’inizio di luglio e

compaiono femmine con uova da aprile a giugno.

Aphthona coerulea (Geoffroy, 1785)

Corotipo: Turanico-Europeo (TUE).

Presenza in Italia: regioni settentrionali e centrali,

Campania, Basilicata, Puglia, Sicilia, Sardegna.

Piante ospiti: specie monofaga, sembra vivere

esclusivamente su Iris pseudacorus.

Note biologiche: A. coerulea è un elemento carat-

CRISOMELIDI (COLEOPTERA CHRYSOMELID AE) DEL MONTE BARRO (ITALIA. LOMBARDIA. LECCO)

203

teristico di ambienti palustri; è comunissima nella pa¬

lude di Ca’ di Sala, mentre la sua presenza, occasio¬

nalmente riscontrata, in altre stazioni è da ritenersi

del tutto accidentale.

Aphthona herbigrada (Curtis, 1837)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutte le regioni.

Piante ospiti: Cistacee del genere Helianthemunr,

sul Monte Barro soprattutto Helianthemnm nummu-

larium.

Note biologiche: per quanto l’insetto sul Monte

Barro sia stato raccolto anche in primavera, diventa

molto comune nella seconda metà dell’estate e all’i¬

nizio dell’autunno. Individui visibilmente immaturi

compaiono già alla fine di giugno ma si trovano nu¬

merosi soprattutto nei mesi di luglio e agosto (verso

la fine di questo mese rappresentano ancora circa il

10% degli esemplari raccolti). Il rapporto maschi/fem¬

mine, calcolato su 2 campioni, ha fornito i seguenti

valori: 0,88 (25.8.1992, dimensione del campione: 150

esemplari; 0,93 (25.9.1992, dimensione del campione:

108 esemplari). Perner (1996: 253, 255), in praterie

aride dell’ex Gemania orientale, ha osservato la pre¬

senza di femmine con uova da fine agosto a fine ot¬

tobre.

Aphthona ovata Foudras, 1860

Corotipo: Europeo (EUR).

Presenza in Italia: Italia settentrionale, Toscana,

Lazio, Calabria, Sicilia.

Piante ospiti: Euforbiacee del genere Euphorbia.

Sul Monte Barro comune soprattutto su Euphorbia

dulcis, nei boschi della Val di Faè.

Note biologiche: in un campione del 26 settembre

è stata riscontrata la presenza di un maschio e di una

femmina leggermente immaturi.

Aphthona atrovirens (Foerster, 1 849)

Corotipo: Centroeuropeo (CEU).

Presenza in Italia: Friuli-Venezia Giulia, Trentino-

Alto Adige, Lombardia, Piemonte, Toscana, Marche,

Lazio, Abruzzo, Molise (Matese: M.te Miletto, dato

inedito), Calabria.

Piante ospiti: secondo Weise (1893: 1137)

Euphorbia cyparissias L., secondo altri autori

(Mohr, 1966: 217; Warchalowski: 1978: 41; Biondi,

1990: 114) Helianthemum e Linum; sul Monte Barro

quasi tutti gli esemplari sono stati raccolti, insieme

ad Aphthona ovata , su Euphorbia dulcis, in prati del¬

la Val di Faè, ai margini di boschi dell’alleanza Car-

pinion betuli.

Longitarsus (s. str.) pellucidus (Foudras, 1860)

Corotipo: Centroasiatico-Europeo-Mediterraneo

(CEM). La specie è presente anche nella regione

Neartica, probabilmente per effetto di importazione.

Presenza in Italia: tutte le regioni.

Piante ospiti: Convolvulacee, soprattutto genere

Convolvulus.

Longitarsus (s. str.) succineus succineus (Foudras,

1 1860)

Corotipo: Paleartico (PAL). La specie è presente

anche nella regione Neartica probabilmente per ef¬

fetto di importazione.

Presenza in Italia: tutte le regioni.

Piante ospiti: Convolvulacee, Plantaginacee, La-

miacee, Boraginacee, Asteracee.

Note biologiche: è probabile che l'insetto abbia

uno sviluppo larvale primaverile, infatti sul Monte

Barro gli adulti sono relativamente rari in maggio,

mentre si riscontra una presenza massiccia di esem¬

plari immaturi nei mesi di giugno e luglio e di femmi¬

ne con uova in settembre. In un campione di 81 esem¬

plari, raccolto il 18.6.1991 e formato interamente da

individui più o meno immaturi, il rapporto maschi/fem¬

mine ha fornito il valore 1,25. Perner (1996: 252-254),

basandosi sul comportamento della specie in praterie

aride dell’ex Germania orientale, ritiene che nel L.

succineus gli stadi di svernamento possano essere

l'uovo, la larva o la pupa; egli ha osservato femmine

con uova da fine giugno a fine agosto e individui im¬

maturi dall’inizio di maggio alla fine di giugno.

Longitarsus (s. str.) noricus Leonardi, 1976

Corotipo: Centroeuropeo (CEU).

Presenza in Italia: Friuli-Venezia Giulia, Trentino-

Alto Adige, Veneto, Lombardia e Piemonte.

Piante ospiti: Plantaginacee del genere Plantago ,

Lamiacee del genere Salvia, Asteracee.

Longitarsus (s. str.) rubiginosus (Foudras, 1860)

Corotipo: Sibirico-Europeo (SIE). La specie è

presente anche nella regione Neartica probabilmente

per effetto di importazione.

Presenza in Italia: Friuli-Venezia Giulia, Trentino

Alto Adige, Lombardia, Piemonte, Toscana, Umbria,

Lazio, Abruzzo, Puglia, Basilicata, Sardegna.

Piante ospiti: Convolvulacee con particolare pre¬

ferenza per il genere Calystegia.

Longitarsus tabidus (Fabricius, 1775)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutte le regioni.

Piante ospiti: Scrofulariacee del genere Verba-

scum.

Longitarsus (s. str.) nigrofasciatus nigrofasciatus

(Goeze, 1977)

Corotipo: Turanico-Europeo-Mediterraneo (TEM).

Presenza in Italia: tutte le regioni.

Piante ospiti: Scrofulariacee dei generi Verbascum

e Scrophularia.

Longitarsus (s. str.) foudrasi Weise, 1893

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: Friuli-Venezia Giulia, Veneto,

Lombardia (prima segnalazione), Piemonte.

Piante ospiti: Scrofulariacee del genere Verba¬

scum.

Note: l’insetto è stato trovato in due soli esempla¬

ri il 26.IX.92, lungo un sentiero che va da Galbiate

verso la località di S. Michele.

Longitarsus (s. str.) lycopi (Foudras, 1860)

Corotipo: Turanico-Europeo-Mediterraneo (TEM).

Questa specie penetra marginalmente anche nella re¬

gione Afrotropicale.

Presenza in Italia: tutte le regioni.

Piante ospiti: Lamiacee dei generi Mentha e Lyco-

pus.

Note: questa specie è del tutto sporadica all’interno

del parco, in quanto tipica di ambienti molto umidi; ri¬

sulta invece comunissima nella palude a Cà di Sala.

204

CARLO LEONARDI & DAVIDE SASSI

Longitarsus (s. str.) obliteratus (Rosenhauer, 1847)

Corotipo: Turanico-Europeo (TUE).

Presenza in Italia: tutta la Penisola.

Piante ospiti: Lamiacee. Sul Monte Barro sembra

frequentare soprattutto i generi Stachys, Thymus e

Origanum.

Note biologiche: Perner (1996: 251-252) lo ritiene

specie xerotermofila; in praterie aride (Teucrio-Sesle-

rieti) dell’ex Germania orientale segnala la presenza

di femmine con uova da aprile a giugno e da settem¬

bre a novembre e di individui immaturi da luglio ad

agosto. Sul Monte Barro abbiamo riscontrato la pre¬

senza di femmine con uova da fine marzo a fine mag¬

gio e raccolto individui immaturi in agosto, settembre

e ottobre. Il rapporto maschi/femmine, calcolato su

quattro campioni, ha fornito i seguenti valori: 1,83

(23.5.1991, dimensioni del campione: 34 esemplari);

0,54 (25.8.1992, dimensione del campione: 17 esem¬

plari); 3,6 (25.9.1992, dimensione del campione: 23

esemplari); 0,54 (10.10.1990, dimensione del campio¬

ne 17 esemplari).

Longitarsus (s. str.) salviae Gruev, 1975

Corotipo: Centroeuropeo (CEU).

Presenza in Italia: Friuli-Venezia Giulia, Veneto,

Lombardia, Puglia.

Piante ospiti: Lamiacee del genere Salvia.

Note biologiche: Perner (1996: 252-253) lo ritiene

specie xerotermofila; in praterie aride (Teucrio-Sesle-

rieti) dell’ex Germania orientale segnala la presenza di

femmine con uova da aprile (immediatamente dopo lo

svernamento) all'inizio di giugno. Sul Monte Barro ab¬

biamo riscontrato la presenza di femmine con uova nei

mesi di marzo, aprile e maggio e raccolto numerosi

esemplari fortemente immaturi nei mesi di agosto e set¬

tembre. Il rapporto maschi/femmine, calcolato su 3 cam¬

pioni, ha fornito i seguenti valori: 2 (10. VI. 1991, dimen¬

sione del campione: 12 esemplari); 1,93 (25.8.1992, di¬

mensione del campione: 41 esemplari); 1,13 (26.9.1992,

dimensione del campione: 17 esemplari).

Longitarsus (s. str.) helvolus Kutschera, 1863

Corotipo: Cetroeuropeo (CEU).

Presenza in Italia: Friuli-Venezia Giulia, Lombar¬

dia, Liguria, Toscana, Calabria, Sicilia (?).

Piante ospiti: Lamiacee ( Teucrium chamaedrys ).

Note biologiche: Doguet (1993) scrive di averlo

raccolto sempre in stazioni calde su terreni calcarei.

Perner (1996: 249-250) lo ritiene specie xerotermofi¬

la; in praterie aride (Teucrio-Seslerieti) dell’ex Ger¬

mania orientale egli ha riscontrato la presenza di

femmine con uova da agosto a maggio e di individui

immaturi da luglio a settembre. Sul Monte Barro è

molto comune, soprattutto in settembre, nelle prate¬

rie cespugliate e con parziale affioramento roccioso

che formano la stazione 6; nelle raccolte compaiono

pochissimi esemplari immaturi. Il rapporto maschi

/femmine, calcolato su due campioni, ha fornito i se¬

guenti risultati: 0,36 (3.9.1991; dimensioni del cam¬

pione: 15 esemplari; 0,20 (25.9.1992; dimensioni del

campione: 73 esemplari).

Note sistematiche: tutte le citazioni di Longitarsus

membranaceus Foudras per la fauna italiana sembra¬

no riferirsi a questo taxon recentemente rivalutato da

Doguet.

Longitarsus (s. str.) melanocephalus (De Geer, 1775)

Corotipo: Turanico-Europeo (TUE).

Presenza in Italia: tutte le regioni.

Piante ospiti: Plantaginacee del genere Plantago.

Note biologiche: sono stati raccolti individui im¬

maturi in giugno e nella seconda metà di settembre.

Il rapporto maschi/femmine, calcolato su tre campio¬

ni, ha fornito i seguenti valori: 1,75 (15.6.1989, di¬

mensione del campione: 11 esemplari); 1,83

(27.6.1989, dimensione del campione: 17 esemplari);

0,71 (30.3.1990, dimensione del campione: 29 esem¬

plari).

Longitarsus (s. str.) niger (Koch, 1803)

Corotipo: Europeo (EUR).

Presenza in Italia: tutte le regioni.

Piante ospiti: Boraginacee (?), Plantaginacee del

genere Plantago. Sul Monte Barro abbiamo raccolto

questa specie in prati in cui erano presenti sia

Echium vulgare che Plantago lanceolata ma non ci è

stato possibile individuare con sicurezza la sua pian¬

ta ospite. Doguet (1994: 201) ha potuto riscontrare la

presenza di numerosi esemplari di L. niger nell’atto

di rodere foglie di Plantago lanceolata e questo dato

biologico conferma la vicinanza sistematica di questo

insetto con L. melanocephalus (De Geer).

Note biologiche: è stata riscontrata la presenza di

esemplari immaturi alla fine di giugno.

Longitarsus (s. str.) exoletus (Linnaeus, 1758)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: Friuli-Venezia Giulia, Trentino-

Alto Adige, Lombardia (prima segnalazione), Ligu¬

ria, Emilia-Romagna, Toscana, Lazio, Abruzzo, Cam¬

pania, Puglia, Sicilia.

Piante ospiti: Boraginacee; sul M. Barro è stato

raccolto solo su Echium vulgare.

Note sistematiche: gli esemplari raccolti sul M.

Barro presentano in parte le caratteristiche cromati¬

che dalla forma tipica, in parte quelle della razza me¬

diterranea rufulus (Foudras, 1860). Condividiamo l’o¬

pinione di Biondi (1990), che ritiene la ssp. rufulus

una semplice forma cromatica, non sufficientemente

distinta da poterle attribuire valore sistematico.

Note biologiche: secondo Miiller (1953), il quale

fa riferimento a un precedente lavoro di Buddeberg,

l’insetto sverna nel terreno come larva, diventa im¬

magine in primavera e depone le uova dalla fine di

giugno a metà agosto; sul Monte Barro noi abbiamo

trovato numerosi esemplari immaturi nel mese di

giugno e femmine con uova da metà luglio all’inizio

di ottobre.

Longitarsus (s. str.) lewisii (Baly, 1874)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: Friuli-Venezia Giulia, Trentino-

Alto Adige, Veneto, Lombardia, Piemonte, Valle

d’Aosta, Emilia-Romagna.

Piante ospiti: Plantaginacee del genere Plantago ; è

noto un caso di allotrofia su Mentha arvensis (Leo¬

nardi & Doguet, 1990: 41).

Note biologiche: per quanto si trovi anche in pri¬

mavera L. lewisii è un tipico insetto tardo-estivo au¬

tunnale; abbiamo raccolto femmine con uova all’ini¬

zio di aprile e a metà giugno, mentre esemplari im¬

maturi compaiono in settembre. Il rapporto

maschi/femmine, calcolato su 2 campioni, ha fornito i

seguenti valori: 1,67 (13.9.1990, dimensione del cam¬

pione: 32 esemplari); 1,10 (20.9.1989, dimensione del

campione: 65 esemplari).

I CRISOMELIDI (COLEOPTERA CHRY SOMELIDAE) DEL MONTE BARRO (ITALIA. LOMB.ARDIA. LECCO)

205

Longitarsus (s. str.) pratensis (Panzer. 1794)

Corotipo: Europeo-Mediterraneo (EUM). La spe¬

cie è presente anche nella regione Neartica probabil¬

mente per effetto di importazione.

Presenza in Italia: tutte le regioni.

Piante ospiti: Plantaginacee del genere Plantcìgo.

Note biologiche: sono state raccolte femmine con

uova a metà del mese di marzo. Il rapporto

maschi/femmine, calcolato su tre campioni, ha fornito

i seguenti risultati: 1,8 (14.3.1990, dimensione del

campione: 42 esemplari); 1,71 (10.6.1991; dimensione

del campione: 19 esemplari); 1,73 (20.9.1989, dimen¬

sione del campione: 71 esemplari).

Longitarsus (s. str.) longiseta Weise, 1889

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: Friuli-Venezia Giulia, Trentino-

Alto Adige, Lombardia, Piemonte.

Piante ospiti: Plantaginacee del genere Plantago e

Scrofulariacee del genere Veronica.

Note biologiche: abbiamo riscontrato la presenza

di individui immaturi all’inizio di agosto e nella se¬

conda decade di settembre, e di femmine con uova

dalla fine di maggio alla seconda decade di giugno. Al¬

cuni campioni ricavati da raccolte effettuate nei mesi

di marzo, giugno e settembre fanno credere che i ma¬

schi siano di norma più frequenti delle femmine, ma

questa impressione non è confermata dall’esame di

materiale proveniente da altre località (in un campio¬

ne di 48 esemplari, in gran parte immaturi, raccolto in

Val Vigezzo il 27.8.1971 la sex ratio è risultata 1,00).

Longitarsus nasturtii (Fabricius, 1972)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: Friuli-Venezia Giulia, Veneto,

Trentino- Alto Adige, Lombardia, Piemonte, Toscana,

Umbria, Lazio, Abruzzo, Calabria.

Piante ospiti: Boraginacee, soprattutto Symphy-

tum officinale.

Note biologiche: L. nasturtii vive generalmente in

ambienti piuttosto umidi; l’abbiamo rinvenuto esclu¬

sivamente nella palude di Ca’ di Sala.

Longitarsus (s. str.) holsaticus (Linnaeus, 1758)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: Italia settentrionale e centrale,

Campania.

Piante ospiti: Scrofulariacee dei generi Veronica,

Pedicularis e Gratiola.

Longitarsus (s. str.) luridus (Scopoli, 1763)

Corotipo: Paleartico (PAL). La specie è presente

anche nella regione Neartica probabilmente per ef¬

fetto di importazione.

Presenza in Italia: tutte le regioni.

Piante ospiti: Ranuncolacee dei generi Ranunculus

e Clematis, Boraginacee dei generi Symphytum e Pol¬

monaria, Lamiacee del genere Clinopodium, Plantagi¬

nacee del genere Plantago, Dipsacacee del genere Suc¬

cisa, Scrofulariacee del genere Rhinanthus.

Note biologiche: abbiamo raccolto femmine con

uova nella seconda metà di aprile e individui imma¬

turi da metà giugno a metà settembre, con un massi¬

mo di presenza da fine giugno a metà luglio. Il rap¬

porto fra i due sessi (abbastanza vicino a 1) non sem¬

bra variare significativamente dei diversi momenti

dell’anno.

Longitarsus (s. str.) fulgens (Foudras, 1860)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Lombardia, Piemonte.

Piante ospiti: Lamiacee dei generi Mentita, Lyco-

pus e Scutellaria.

Note biologiche: L. fulgens è un insetto caratteri¬

stico di prati molto umidi. Abbiamo riscontrato la sua

presenza solo nella palude di Ca’ di Sala, dove peral¬

tro era molto raro.

Longitarsus (s. str.) brunneus (Duftschmid, 1825)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Friuli-Venezia Giulia, Lombar¬

dia (prima segnalazione) Piemonte, Liguria, Toscana,

Abruzzo, Lazio, Campania, Calabria.

Piante ospiti: Ranuncolacee del genere Thalic-

trum. Secondo Gruev anche Asteracee ( Aster ), Bora¬

ginacee ( Symphytum ) e Lamiacee ( Stachys ). Per

quanto riguarda il Monte Barro l’insetto è stato rac¬

colto costantemente su Thalictrum , prevalentemente

Thalictrum minus.

Note biologiche: abbiamo raccolto femmine con

uova dalla prima decade di maggio alla fine di giugno

e un maschio fortemente immaturo a metà luglio;

nessun esemplare di L. brunneus è stato raccolto in

agosto, settembre e ottobre, pur essendo soprattutto

questi i mesi in cui, sulla base dell’esperienza acquisi¬

ta dall’esame di materiale di altra provenienza (Ve¬

nezia Giulia), dovrebbero comparire individui imma¬

turi. Per quanto riguarda la proporzione fra i due ses¬

si abbiamo rilevato una maggiore presenza di maschi,

soprattutto nel mese di maggio

Longitarsus (s. str.) minusculus (Foudras, 1860)

Corotipo: S-Europeo (SEU).

Presenza in Italia: Friuli-Venezia Giulia, Lombar¬

dia (prima segnalazione), Piemonte, Liguria, Emilia-

Romagna, Toscana, Lazio, Puglia (?).

Piante ospiti: Lamiacee, soprattutto dei generi Sta¬

chys, Teucrium, Sideritis e Salvia.

Note sistematiche: L. minusculus è stato citato an¬

che di Lucania, Sicilia (Biondi, 1990: 145) e Sardegna

(Leonardi, 1975: 9; Biondi, 1990: 145) dove invece

sembra essere sostituito da L. anacardius (All.); que¬

st’ultimo è un taxon a distribuzione sud-mediterra-

nea che è stato messo in sinonimia del L. minusculus

da Warchalowski (1969); successivamente uno di noi

(Leonardi) ebbe modo di esaminare due femmine

della serie tipica di L. anacardius nella collezione

Oberthur e, ritenendo il taxon una specie distinta, de¬

signò una di esse come Lectotypus, designazione che

è però rimasta in litteris. Doguet nel volume sugli Al-

ticinae della serie Faune de France (1994: 216) rivalu¬

ta L. anacardius, considerandolo sottospecie di L. mi¬

nusculus', le importanti differenze (soprattutto nella

conformazione della spermateca: Figg. 17-26) che

permettono di separarlo dal L. minusculus, fanno

preferire l’ipotesi che esso sia effettivamente una

specie a sè stante (]). Nel complesso le due entità si

possono riconoscere in base ai seguenti caratteri:

1 Microttero. Le/Lp (v. Fig. 27) nei maschi normal¬

mente < 3,20, nelle femmine normalmente < 3,40.

lp/Lp (v. Fig. 28) nei maschi normalmente < 1,45,

nelle femmine normalmente < 1,50. Edeago in vi¬

sione ventrale (Figg. 9a-12a) con una leggera

strozzatura circa ai 3/5 distali della sua lunghezza

e con apice subtriangolare, in visione laterale

206

CARLO LEONARDI & DAVIDE SASSI

(Figg. 9b-12b) caratterizzato quasi sempre da una

leggera deflessione apicale. Spermateca (Figg. 22-

26) con parte distale molto larga e non invaginata

nella parte basale; ansa del ductus appressata al

corpo della spermateca. Europa centrale e meri¬

dionale . L. minusculus (Foudras)

1’ Spesso macrottero. Le/Lp (v. Fig. 27) nei maschi

normalmente > 3,40, nelle femmine normalmen¬

te > 3,50. lp/Lp (v. Fig. 28) nei maschi normal¬

mente > 1,45, nelle femmine normalmente > 1,50.

Edeago in visione ventrale (Figg. 13a-16a) nella

metà distale con lati praticamente paralleli e api¬

ce di regola arrotondato, in visione laterale (Figg.

13b-16b) con deflessione apicale in genere più

debole o del tutto assente. Spermateca (Figg. 17-

21) con parte distale più sottile e debolmente in¬

vaginata nella parte basale; ansa del ductus più

staccata dal corpo della spermateca. Is. Baleari,

Sardegna, Sicilia, Lucania, Maghreb .

. L. anacardius (Allard)

Figg. 9-16 - Edeagi di Longitarsus minusculus (9-12) e L. anacardius (13-16) in visione ventrale (a) e laterale (b). I numeri

piccoli indicano la lunghezza elitrale in millimetri degli esemplari disegnati. Località degli esemplari raffigurati: Monte Bar¬

ro (9-10); Lazio. Riofreddo (11); Bohemia, Karlstein (12); Algeria, Constantine (13); Algeria, E1 Meridj (14);Tunisia, Le Kef

(15); Sardegna, Gennargentu (16).

Figg. 17-26 - Spermateche di Longitarsus anacardius (17-21) e L.

minusculus (22-26) in visione dorsale. I numeri piccoli indicano la

lunghezza elitrale in millimetri degli esemplari disegnati. Località

degli esemplari raffigurati: Basilicata, Policoro (17); Algeria, Al-

gier («ex Musaeo Allard»): Lectotypus + Paralectotypus (18-19);

Algeria, E1 Meridj (20); Algeria, Bòne (21); Istria, Mali Kras (22);

Friuli Venezia Giulia, Duino (23); Monte Barro (24); Lazio, Rio¬

freddo (25); Friuli Venezia Giulia, Bivio Aurisina (26).

Longitarsus (s. str.) linnaei linnaei (Duftschmid,

1825)

Corotipo: S-Europeo (SEU).

Presenza in Italia: tutte le regioni.

Piante ospiti: Boraginacee, soprattutto del genere

Symphytum.

Note biologiche: sul Monte Barro è stato raccolto

solo nei boschi di latifoglie della Val Faè.

Longitarsus (s. str.) pinguis Weise, 1888

Corotipo: S-Europeo (SEU).

Presenza in Italia: Friuli-Venezia Giulia, Veneto,

Trentino-Alto Adige, Lombardia, Emilia-Romagna,

Abruzzo.

Piante ospiti: Boraginacee. All’interno del Parco

del Monte Barro abbiamo raccolto il L. pinguis qua¬

si esclusivamente in Val Faè, senza riuscire a indivi¬

duare con certezza la pianta ospite. L’insetto è invece

molto comune nelle vicinanze del Lago d’Alserio, a

poca distanza dal Monte Barro, dove è stato raccolto

da uno di noi (Leonardi) su Pulmonaria officinalis.

Note biologiche: è stata riscontrata la presenza di

individui immaturi nel mese di settembre.

Note sistematiche: gli esemplari alpini di L. pin¬

guis fanno pensare a forme molto scure di L. luridus

(Scop.), dalle quali si differenziano per le elitre in ge¬

nere più largamente arrotondate all’apice (Figg. 29-

31) e digradanti sui fianchi in un arco un po’ meno re-

(') A lavoro ultimato abbiamo ricevuto un articolo di Doguet, Bastazo, Bergeal & Vela in cui si considera L. anacardius spe¬

cie distinta e si fissa come Lectotypus l’esemplare di cui è rappresentata la spermateca nella fig. 18 della nostra pubblica¬

zione.

I CRISOMELIDI (COLEOPTERA CHRYSOMELIDAE) DEL MONTE BARRO (ITALIA, LOMBARDIA. LECCO) 207

MASCHI FEMMINE

Fig. 27 - Variabilità della lunghezza delle elitre e del pronoto in Longitarsus anacardius e L. minusculus (valori in millime¬

tri). Le rette che descrivono la regressione di Le su Lp sono tracciate con una linea continua, quelle che descrivono la re¬

gressione di Lp su Le sono tracciate con una linea tratteggiata. L’analisi della covarianza applicata alle rette ha fornito i se¬

guenti risultati: maschi: F= 93,57 (Lp su Le, differenza altamente significativa); F= 64,53 (Le su Lp, differenza altamente si¬

gnificativa); femmine: F= 47,44 (Lp su Le, differenza altamente significativa); F= 30,23 (Le su Lp, differenza altamente si¬

gnificativa).

golare. Nella regione appenninica la forma elitrale

presenta una variabilità più marcata (Figg. 32-41) e

possono comparire individui con elitre accentuata-

mente compresse ai lati e debolmente subtroncate,

che fanno pensare piuttosto a L. anchusae (Paykull)

o a L. bonnairei (Allard). Altrettanto variabili sono il

rapporto lp/Lp, i cui valori medi comunque non sem¬

brano essere mai inferiori a 1,30, e la conformazione

dell’organo copulatore (Figg. 44-50): nell’edeago de¬

gli esemplari appenninici in genere il lembo interno

del bordo laterale è fortemente inclinato verso il fon¬

do della scanalatura ventrale, cosicché il bordo appa¬

re più stretto e la scanalatura più larga, inoltre l’api¬

ce è in visione ventrale abitualmente meno ottuso

che nella forma alpina e in visione laterale media¬

mente meno deflesso; gli esemplari quasi privi di de¬

flessione edeagica apicale (Figg. 46-47) ricordano, per

questa caratteristica, L. bulgaricus Gruev.

Esemplari abbastanza simili a quelli europei sono

stati raccolti nella regione caucasica, mentre in Israe¬

le è diffusa una forma con protorace relativamente

poco trasverso (lp/Lp abitualmente < 1,25) e margine

apicale delle elitre costantemente subtroncato (Figg.

42-43) che, pur essendo di chiara derivazione dal L.

pinguis, col quale ha in comune sia la conformazione

dell’edeago (Fig. 51) che quella della spermateca, è

stata trattata da Furth (1979: 116) come specie distin¬

ta col nome di L. truncatellus Weise.

Per la relativa brevità della callosità elitropleurale,

che si ferma all’inizio del margine apicale delle elitre,

e per la presenza di individui con elitre fortemente

compresse e subtroncate L. pinguis dovrebbe essere

incluso nel sottogenere Testergus Wse sensu Bechyné

(= Truncatus Pai.), ipotesi, questa, non sconvolgente,

dato che Heikertinger lo trattava addirittura come va¬

rietà di L. anchusae, cioè di una specie che Lopatin

(1977) include in questo sottogenere. D’altro canto, la

prima di queste caratteristiche può comparire, con

maggiore o minore frequenza, anche in alcuni Longi¬

tarsus attribuiti al sottogenere tipico, quali, per esem¬

pio, L. reichei (All.), L. medvedevi Shap., L. albineus

(Foudr.), e L. absynthii Kutsch., mentre le altre, data la

loro variabilità, fanno di L. pinguis, una specie di tran¬

sizione fra Longitarsus s. str. e Testergus Weise sensu

Bechyné. Riteniamo pertanto che quest’ultimo (che

Bechyné proponeva addirittura come genere distinto)

sia troppo insufficientemente caratterizzato dal punto

di vista morfologico per poter essere considerato come

un sottogenere distinto, pur essendo probabile che

molti dei taxa che vi sono inclusi formino realmente un

gruppo naturale. È questa la posizione sostenuta dalla

maggior parte degli specialisti (v. Doguet, 1994). Una

sua eventuale rivalutazione potrà essere, a nostro avvi¬

so, solo successiva a uno studio filogenetico accurato

dell’intero genere Longitarsus.

Non intendiamo invece entrare nel merito della

validità del sottogenere Testergus inteso nel senso

originale, che Weise istituì per due specie caucasiche

208

CARLO LEONARDI & DAVIDE SASSI

MASCHI

FEMMINE

su lp sono tracciate con una linea tratteggiata. L’analisi della covarianza applicata alle rette ha fornito i seguenti risultati:

maschi: F= 7,57 (lp su Lp, differenza significativa); F= 22,51 (Lp su lp, differenza altamente significativa); femmine: F= 12,54

(lp su Lp, differenza altamente significativa); F= 25,97 (Lp su lp, differenza altamente significativa).

(L. ledevi e L. pubescens) da lui stesso descritte, ca¬

ratterizzate dalle elitre saldate e pubescenti.

Ericacee, Onagracee, Litracee, Cistacee, Rosacee,

Scrofulariacee, Betulacee, Fagacee.

Attica oleracea (Linneo, 1758)

Corotipo; Asiatico-Europeo (ASE).

Presenza in Italia: tutte le regioni.

Piante ospiti: soprattutto poligonacee ma anche

Figg. 29-43 - Silouette elitrale in Longitarsus pinguis (29-41) e L.

truncatellus (42-43). Località degli esemplari raffigurati: Monte

Barro (20-30); Nieder Bayern (31); Emilia Romagna, Campigna

(32-34); Emilia Romagna, Passo Calla (35); Campania, Valle Pia¬

na (M.ti Picentini) (36); Abruzzo, Monte Marsicano (37); Molise,

Monte Miletto (38); Abruzzo, Gran Sasso (39); Abruzzo,

Blockhaus (40-41); Israele, N. Amud (42-43).

Attica carinthiaca (Weise, 1888), (Fig. 52)

Corotipo: Turanico-Europeo (TUE).

Presenza in Italia: Alpi (finora citata in modo ge¬

nerico delle Alpi Orientali e, dubitativamente, delle

Alpi Marittime; la presenza di questa specie sul Mon¬

te Barro costituisce il primo dato sicuro per le Alpi

Italiane), Lazio.

Piante ospiti: come piante ospiti di A. carinthiaca

figurano Sanguisorba minor (Rosacee) e Lathyrus

pratensis (Fabacee); data la rarità di questa specie

non siamo riusciti a confermare questi dati biologici

Attica impressicollis Reiche, 1862

Corotipo: Turanico-Europeo-Mediterraneo (TEM)

Presenza in Italia: tutte le regioni.

Piante ospiti: Enoteracee del genere Epilobium ,

Litracee ( Lythrum salicaria), Asteracee ( Eupatorium

cannabinum.

Note biologiche: Euforbiacee del genere Mercu¬

riali. Questa specie frequenta biotopi umidi. L’ab¬

biamo raccolta, in un numero limitato di esemplari,

solo nella palude di Ca’ di Sala.

Hermaeophaga mercurialis (Fabricius, 1792)

Corotipo: Europeo (EUR)

Presenza in Italia: regioni settentrionali, Lazio,

Abruzzo, Puglia.

CRISOMELIDI (COLEOPTERA CHRY SOMELID AE) DEL MONTE BARRO (ITALIA. LOMBARDIA. LECCO)

209

Figg. 44-51 - Edeagi di Longitarsus pinguis (44-50) e L. truncatel-

lus (51) in visione ventrale (a) e laterale (b). I numeri piccoli in¬

dicano la lunghezza elitrale in millimetri degli esemplari disegna¬

ti. Località degli esemplari raffigurati: Gòrz Piava (44); Monte

Barro (45); Liguria. Rezzoaglio d’Aveto (46); Emilia Romagna,

Campigna (47); Abruzzo, Monte Marsicano (48); Abruzzo,

Blockhaus (49-50); Israele (51).

Piante ospiti: Euforbiacee del genere Mercurialis.

Questo insetto è stato raccolto solo in Val di Faè, do¬

ve è frequente soprattutto nel sottobosco.

Lythraria salicariae (Paykull, 1800)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: regioni settentrionali e centrali,

Campania, Basilicata, Calabria.

Piante ospiti: Primulacee del genere Lysimachia ,

Litracee ( Lythrum salicaria).

Figg. 52-53 - Edeagi di Altica carinthiaca (52) e Asiorestia crassi-

cornis (53) del Monte Barro in visione ventrale (a) e laterale (b).

I numeri piccoli indicano la lunghezza elitrale in millimetri degli

esemplari disegnati.

Note biologiche: questa specie è caratteristica di

biotopi umidi; l’abbiamo raccolta solo nella palude di

Ca’ di Sala.

Asiorestia brevicollis (J. Daniel. 1904)

Corotipo: Sud-Europeo (SEU) (endemita Alpino-

Appenninico).

Presenza in Italia: tutte le regioni peninsulari ad

esclusione di Valle d'Aosta, Piemonte e Liguria.

Piante ospiti: Asteracee del genere Cirsium.

Note biologiche: questo insetto sembra predilige¬

re ambienti umidi; ne abbiamo raccolto una sola fem¬

mina nella palude di Ca' di Sala, ed era già noto del

Lago di Annone.

Asiorestia transversa (Marsham, 1802)

Corotipo: Europeo (EUR).

Presenza in Italia: regioni peninsulari e Sardegna.

Piante ospiti: Asteracee soprattutto del genere

Cirsium , Boraginacee (?), Plumbaginacee (?).

Note biologiche: il rapporto maschi/femmine ha

fornito il valore 0,79 in un campione di 41 esemplari

raccolto il 15.6.1990.

Asiorestia ferruginea (Scopoli, 1763)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutte le regioni.

Piante ospiti: Poacee, Fabacee, Poligonacee, Aste¬

racee, Boraginacee, Cannabacee, Urticacee.

Asiorestia crassicornis crassicornis (Faldermann,

1837), (Fig. 53)

Corotipo: S-Europeo (SEU).

Presenza in Italia: Friuli-Venezia Giulia, Veneto,

Lombardia (prima segnalazione per la regione), Val¬

le d’Aosta, Liguria, Emilia-Romagna (M. Fumaiolo,

dato inedito).

Piante ospiti: Asteracee del genere Centaurea.

O restia electra electra Gredler, 1868

Corotipo: S-Europeo (SEU) (endemita Alpino)

Presenza in Italia: ssp. electra: Trentino- Alto Adige

(Alpi Giudicane), Lombardia; ssp. brunnea

(Halbherr, 1898); Trentino- Alto Adige, Veneto.

Note biologiche: questa specie non frequenta la

vegetazione; la si raccoglie sotto sassi, fra i muschi o

nelle lettiere. Sul Monte Barro ne è stato raccolto un

solo maschio in Val Faè a m 620 di quota.

Derocrepis sodalis (Kutschera, 1860)

Corotipo: S-Europeo (SEU) (endemita Alpino-

Appenninico).

Presenza in Italia: regione alpina (dalle Alpi Reti-

che alle Liguri), Appennino centro-settentrionale,

Massiccio del Pollino.

Piante ospiti: Fabacee.

Crepidodera aurea (Geoffroy, 1785)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: regioni settentrionali e centrali,

Campania, Basilicata, Calabria, Sicilia.

Piante ospiti: Salicacee.

Crepidodera aurata (Marsham, 1802)

Corotipo: Asiatico-Europeo (ASE)

Presenza in Italia: tutte le regioni.

Piante ospiti: Salicacee.

Note sistematiche: di questa specie Heikertinger

210

CARLO LEONARDI & DAVIDE SASSI

(1910: (54)) ha descritto, su esemplari di Morea, la

razza peloponnesiaca. Noi abbiamo potuto esaminare

una serie di esemplari (MM, CZ) raccolti in Pelopon¬

neso (Korinthia: dint. Kaliani, 13. IX. 1995) da S. Zoia,

che corrispondono alla descrizione di questo taxon;

essi non appartengono sicuramente alla specie aura¬

ta, dalla quale si distinguono, oltre che per la confor¬

mazione dell’edeago e della spermateca, anche per

caratteristiche esterne, quali, soprattutto, la relativa

opacità elitrale. Riteniamo quindi che Crepidodera

peloponnesiaca sia una specie distinta o, forse, una

forma geografica di Cr. nigricoxis All., che conoscia¬

mo solo dalle descrizioni (Gruev & Tomov, 1986: 273,

274; Konstantinov, 1996: 29, 31-32). A favore della se¬

conda ipotesi sembra giocare una notevole rassomi¬

glianza, sia edeagica che spermatecale, fra i due taxa;

in nessuna descrizione di Cr. nigricoxis si accenna

però alla scarsa lucentezza elitrale, che caratterizza

invece Cr. peloponnesiaca.

Epitrix pubescens (Koch, 1803)

Corotipo: Turanico-Europeo (TUE).

Presenza in Italia: regioni settentrionali e centrali,

Basilicata, Sardegna.

Piante ospiti: Solanacee.

Podagrica fuscicomis (Linneo, 1766)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutte le regioni.

Piante ospiti: Malvacee, occasionalmente Astera-

cee del genere Carduus.

Note sistematiche: per la punteggiatura elitrale re¬

lativamente forte gli esemplari del Monte Barro sem¬

brano appartenere alla forma mediterranea, abitual¬

mente trattata come sottospecie, col nome di chryso-

melina (Waltl, 1835); il valore di questa razza geogra¬

fica può essere facilmente messo in discussione in

considerazione dell’elevata variabilità della specie e

dell’esistenza di troppe popolazioni con caratteristi¬

che intermedie.

Mantura (s. str.) obtusata (Gyllenhal, 1813)

Corotipo: Europeo (EUR).

Presenza in Italia: Friuli-Venezia Giulia, Veneto,

Lombardia, Piemonte, Emilia-Romagna, Toscana,

Lazio, Campania, Calabria, Sicilia.

Piante ospiti: Poligonacee del genere Rumex.

Chaetocnena (Tlanoma) concinna (Marsham, 1802)

Corotipo: Asiatico-Europeo (ASE)

Presenza in Italia: regioni peninsulari, Sicilia, Sar¬

degna (?).

Piante ospiti: Poligonacee dei generi Polygonum e

Rumex , Chenopodiacee del genere Atriplex.

Chaetocnema ( Tlanoma ) laevicollis (C. G. Thom¬

son, 1866)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: Friuli-Venezia Giulia, , Veneto,

Lombardia, Piemonte, Lazio.

Piante ospiti: Poligonacee, occasionalmente Bras-

sicacee.

Chaetocnema (Tlanoma) tibialis (Illiger, 1807)

Corotipo: Turanico-Europeo-Mediterraneo (TEM).

Presenza in Italia: tutte le regioni.

Piante ospiti: Chenopodiacee.

Chaetocnema ( Tlanoma ) conducta (Motschulski, 1838)

Corotipo: Turanico-Europeo-Mediterraneo (TEM),

secondariamente Afrotropicale.

Presenza in Italia: tutte le regioni.

Piante ospiti: Ciperacee, Giuncacee, Poacee.

Chaetocnema (s. str.) confusa (Bohemann, 1851)

Corotipo: Turanico-Europeo (TUE)

Presenza in Italia: Friuli-Venezia Giulia, Veneto,

Piemonte, Campania, Basilicata, Calabria.

Piante ospiti: Ciperacee del genere Carex , Giunca¬

cee del genere Juncus.

Note biologiche: si tratta di un insetto tipico di

ambienti umidi: l’abbiamo raccolto solo nella palude

di Ca’ di Sala.

Chaetocnema (s. str.) arida Foudras, 1860

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: regioni settentrionali e centrali,

Basilicata, Sicilia, Sardegna.

Piante ospiti: Ciperacee, Giuncacee.

Chaetocnema (s. str.) hortensis (Geoffroy, 1785)

Corotipo: Paleartico (PAL), secondariamente

Afrotropicale.

Presenza in Italia: tutte le regioni.

Piante ospiti: Poacee, Ciperacee (?).

Sphaeroderma testaceum (Fabricius, 1775)

Corotipo: Europeo (EUR).

Presenza in Italia: regioni peninsulari, Sicilia.

Piante ospiti: Asteracee dei generi Carduus e Cir-

sium.

Sphaeroderma rubidum (Graèlls, 1858)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutte le regioni.

Piante ospiti: Asteracee soprattutto dei generi

Centaurea , Carduus e Cirsium.

Argopus ahrensi (Germar, 1817)

Corotipo: S-Europeo (SEU).

Presenza in Italia: regioni nordorientali, Lombar¬

dia, Piemonte, Toscana, Abruzzo, Calabria.

Piante ospiti: Ranuncolacee del genere Clematis.

0.3 mm

Fig. 54 - Edeago di Dibolia foersteri del Monte Barro in visione

ventrale (a) e laterale (b). Il numero piccolo indica la lunghezza

elitrale in millimetri dell’esemplare disegnato.

I CRISOMELIDI (COLEOPTERA CHRY SOMELID AE) DEL MONTE BARRO (ITALIA. LOMBARDIA. LECCO)

211

Dibolia foersteri Bach, 1859, (Fig. 54)

Corotipo: Europeo (EUR).

Presenza in Italia: Friuli-Venezia Giulia, Veneto,

Trentino-Alto Adige, Lombardia (prima segnalazio¬

ne per questa regione), Piemonte, Lazio.

Piante ospiti: Lamiacee ( Stachys officinalis).

Dibolia cryptocephala (Koch, 1803)

Corotipo: Turanico-Europeo (TUE).

Presenza in Italia: regioni settentrionali, Toscana,

Abruzzo, Basilicata, Calabria, Sicilia.

Piante ospiti: Lamiacee, probabilmente dei generi

Thymus e Salvia. Salvia pratensis è presente sul Mon¬

te Barro in tutte e tre le stazioni in cui abbiamo rac¬

colto questo insetto.

Psylliodes affinis (Paykull, 1799)

Corotipo: Centroasiatico-Europeo-Mediterraneo

(CEM)

Presenza in Italia: regioni settentrionali e centrali,

Campania, Basilicata, Sardegna.

Piante ospiti: Solanacee, soprattutto Solarium dul¬

camara.

Psylliodes napi (Fabricius, 1792)

Corotipo: Turanico-Europeo-Mediterraneo (TEM).

Presenza in Italia: tutte le regioni.

Piante ospiti: Brassicacee.

Psylliodes toelgi Heikertinger, 1914

Corotipo: S-Europeo (SEU).

Presenza in Italia: Friuli-Venezia Giulia, Trentino-

Alto Adige, Lombardia, Piemonte, Val d’Aosta, Lazio

(Terminillo: Sella di Leonessa, dato inedito).

Piante ospiti: Brassicacee (Biscutella laevigata).

Note biologiche: individui immaturi sono stati rac¬

colti nei mesi di giugno e di luglio.

Note sistematiche: Ps. toelgi è una specie montana

molto vicina a Ps. brisouti Bedel; se ne distingue so¬

prattutto per il primo protarsomero dei maschi mo¬

destamente dilatato, per l’assenza del tipo alare bra-

chittero (nella popolazione del Monte Barro domina

la forma mesottera con una percentuale di circa il

15% di individui macrotteri) e per l’edeago (Figg. 57-

58) mediamente più esile e meno angolosamente ar¬

cuato; ulteriori particolarità edeagiche si riscontrano

nella scanalatura ventrale, dove la parte basale è re¬

lativamente lunga e la rigatura trasversale della par¬

te intermedia è spesso molto debole o del tutto as¬

sente. Il confronto (Figg. 59-60) fra i valori di Le, Lp,

Lt ed Ld ottenuti da un campione di Ps. toelgi del

Monte Barro e quelli ottenuti da un campione di Ps.

brisouti della stessa provenienza conferma inoltre re¬

sistenza di importanti differenze nei valori medi del

rapporto Le/Lp ed Lt/Ld, in sostanziale accordo con

quanto fu già scritto da uno di noi (Leonardi, 1971).

E da notare come gli individui del Monte Barro, for¬

se in relazione alla quota molto bassa (circa 300 m)

del ritrovamento, presentino dimensioni medie note¬

volmente superiori rispetto ai valori medi della spe¬

cie.

Psylliodes brisouti Bedel, 1898

Corotipo: S-Europeo (SEU).

Presenza in Italia: Veneto, Lombardia (prima se¬

gnalazione per questa regione), Piemonte, Val d’Ao¬

sta, Lazio, Abruzzo, Sicilia.

Piante ospiti: Brassicacee del genere Erysimum.

Figg. 55-58 - Edeagi di Psylliodes brisouti (55-56) e Ps. toelgi (57-

58) del Monte Barro in visione ventrale (a) e laterale (b). I nu¬

meri piccoli indicano la lunghezza elitrale in millimetri degli

esemplari disegnati.

Note biologiche: sono stati raccolti diversi indivi¬

dui immaturi nella seconda metà di giugno e all’inizio

di luglio.

Note sistematiche: è interessante osservare come

il Monte Barro sia l’unica località finora nota in cui

sono presenti sia Ps. brisouti Bedel che Ps. toelgi

Heikertinger, a conferma del valore specifico di que¬

sti due taxa che presentano indubbiamente un livello

di affinità assai elevato. Mentre Ps. toelgi vive esclusi¬

vamente su Biscutella laevigata, P. brisouti è stata rac¬

colta solo su Erysimum virgatum , ai margini della sta¬

zione 2; tutti gli esemplari sono risultati brachitteri e

i maschi presentano una forte dilatazione del primo

articolo protarsale oltre che un edeago (Figg. 55-56)

relativamente robusto e quasi angolosamente arcua¬

to; la scanalatura edeagica ventrale presenta spesso

un’evidente rigatura trasversale, che tipicamente in¬

teressa la parte intermedia ma talvolta si estende an-

212

CARLO LEONARDI & DAVIDE SASSI

MASCHI FEMMINE

Fig. 59 - Variabilità della lunghezza delle elitre e del pronoto in esemplari di Psylliodes brisouti e Ps. toelgi del Monte Bar¬

ro (valori in millimetri). Le rette che descrivono la regressione di Le su Lp sono tracciate con una linea continua, quelle che

descrivono la regressione di Lp su Le sono tracciate con una linea tratteggiata. L’analisi della covarianza applicata alle ret¬

te ha fornito i seguenti risultati: maschi: F= 78,71 (Lp su Le, differenza altamente significativa); F= 21,99 (Le su Lp, diffe¬

renza altamente significativa); femmine: F= 54,83 (Lp su Le, differenza altamente significativa); F= 18,41 (Le su Lp, diffe¬

renza altamente significativa).

che sulla parte basale; quest’ultima, non sempre ben

delimitata, è in genere più corta che in Ps. toelgi. I va¬

lori di Le, Lp, Lt ed Ld, messi a confronto con quelli

ottenuti da un campione di Ps. toelgi del Monte Bar¬

ro, sono riportati nelle Figg. 59-60.

Note geometriche: Ps. brisouti è nel complesso una

specie a gravitazione meridionale, per quanto possa

spingersi molto a nord, fino a raggiungere la punta

meridionale della Svezia (Baranowski, 1980). 1 Ma¬

schio e 1 femmina svedesi conservati presso il Museo

di Storia Naturale di Milano (dono Baranowski) for¬

niscono i seguenti dati morfometrici: maschio: Le =

1,840 mm, Lp - 0,605 mm, Lt = 0,740 mm, Ld - 0,177

mm; femmina: Le = 1,950 mm, Lp = 0,640 mm, Lt =

0,778 mm, Ld = 0,177 mm.

Psylliodes cupreus (Koch, 1803)

Corotipo: Centroasiatico-Europeo-Mediterraneo

(CEM)

Presenza in Italia: tutte le regioni.

Piante ospiti: Brassicacee.

Psylliodes instabilis Foudras, 1860

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: regioni peninsulari, Sicilia.

Piante ospiti: Brassicacee.

Psylliodes dulcamarae (Koch, 1803)

Corotipo: Turanico-Europeo (TUE)

Presenza in Italia: regioni settentrionali e centrali,

Campania, Basilicata, Calabria.

Piante ospiti: Solanacee ( Solarium dulcamara).

Cassida (Hypocassida) subferruginea Schrank, 1776

Corotipo: Paleartico (PAL).

Presenza in Italia: tutte le regioni.

Piante ospiti: Convolvulacee ( Convolvulus ); spo¬

radicamente Chenopodiacee (Beta). Un esemplare fu

raccolto in Monte Barro su Calystegia sepium.

Cassida (Odontionycha) viridis viridis Linnaeus, 1758

Corotipo: Paleartico (PAL).

Presenza in Italia: tutte le regioni.

Piante ospiti: specie igro-mesofila, legata a Lamiacee

dei generi Stachys, Mentita, Galeopsis, Lycopus, Salvia.

In Monte Barro fu sempre raccolta su Salvia glutinosa.

Cassida (s. str.) vibex Linnaeus, 1767

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: tutte le regioni.

Piante ospiti: Asteracee ( Cirsium , Carduus, Centau¬

rea , Arctium , Tanacetum , Achillea). In Monte Barro

sembra prevalentemente legata a Centaurea triumfettii.

Cassida (s. str.) ferruginea Goeze, 1777

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: penisola.

I CRISOMELIDI (COLEOPTERA CHRYSOMELID AE) DEL MONTE BARRO (ITALIA. LOMBARDIA. LECCO)

213

MASCHI

FEMMINE

Piante ospiti: Pulicaria dysenterica, su cui fu rac¬

colta anche in Monte Barro.

Note: specie tendenzialmente igrofila.

Cassida (s. str.) rubiginosa rubiginosa Miiller, 1776

Corotipo: Paleartico (PAL).

Presenza in Italia: tutte le regioni.

Piante ospiti: diversi generi di Asteracee.

Cassida (s. str.) denticollis Suffrian, 1844

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: tutta la penisola, nel complesso

piuttosto rara. Tendenzialmente submontana-monta-

na, specialmente al sud.

Piante ospiti: Asteracee (Achillea, Tanacetum ).

Cassida A- str.) sanguinolenta sanguinolenta Miil-

ler, 1776

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: penisola, Sicilia.

Piante ospiti: Asteracee ( Achillea , Tanacetum ).

Note: raccolte femmine con uova a metà luglio.

Cassida (Mionycha) margaritacea Schaller, 1783

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: penisola, Sicilia.

Piante ospiti: Cariofillacee ( Silene , Saponaria , Sper-

gula), Lamiacee (Thymus), Asteracee ( Centaurea ).

Note: specie tendenzialmente xerofila.

Cassida ( Mionycha ) subreticulata Suffrian, 1844

(Fig. 66)

Corotipo: Centroasiatico-Europeo (CAE).

Presenza in Italia: penisola, Sicilia.

Piante ospiti: Cariofillacee ( Silene , Saponaria,

Dianthus ). In Monte Barro raccolta su Saponaria of-

ficinalis.

Note biologiche: nel corso delle ricerche

(16.5.1991) furono raccolti sei esemplari di Cassida

subreticulata ed allevati con foglie fresche di Sapona¬

ria officinalis. Gli esemplari cominciarono subito a

nutrirsi e ad accoppiarsi frequentemente. Gli accop¬

piamenti continuarono, con lo stesso ritmo, almeno

fino alFinizio di luglio. Il giorno stesso della raccolta

iniziarono le prime deposizioni. Dopo breve tempo

(22 maggio) erano già state deposte circa 50 uova,

contenute singolarmente in piccole ooteche trasluci¬

de, formate da un sottile strato di secreto colleterico

ricoprente ciascun germe. Nella maggior parte dei ca¬

si le ooteche vennero applicate alla pagina superiore

delle foglie. La femmina non provvide mai a rivestir¬

le con materiale fecale. Le dimensioni medie delle

uova erano 1,15 mm X 0,58 mm. Quelle della intera

ooteca 1,58 mm X 1,14 mm. Le prime larve compar¬

vero il 29 maggio e iniziarono subito a nutrirsi, pro¬

ducendo piccoli fori subcircolari nella pagina inferio¬

re delle foglie, lasciando generalmente intatta quella

superiore. Come consuetudine per le larve dei cassi-

dini, i residui delle exuvie, parzialmente ricoperti da

214

CARLO LEONARDI & DAVIDE SASSI

un leggero strato di materia fecale, vennero conser¬

vati sulla turca anale, tenuta ripiegata in avanti e sol¬

levata al di sopra del dorso. Se molestate, le larve

scuotevano ritmicamente e con energia la furca al di

sopra dell’addome. Dopo circa un mese (21 giugno) e

quattro mute, le prime larve sgusciate, raggiunte le di¬

mensioni di 4,13 - 4,60 mm, smisero di nutrirsi e si fis¬

sarono ad una foglia con una goccia di sostanza vi¬

schiosa emessa dall’ano, senza liberarsi dei residui

delle mute precedenti, come osservato in altre specie.

Dopo poche ore si trasformarono in pupe e la com¬

parsa dei primi adulti si ebbe il 25 giugno. Appena na¬

te, le immagini sono di un giallo chiarissimo, soltanto

gli occhi e i palpi labiali sono neri. L’apice dell’ultimo

articolo antennale e, in parte, gli altri elementi bocca¬

li sono soltanto leggermente offuscati. La superficie

dorsale è opaca. Dopo poche ore la colorazione nera

interessa anche il labbro superiore. Dopo due giorni

l’esoscheletro elitrale è diventato lucido, si evidenzia¬

no le bozze juxtascutellari, inzia a vedersi per traspa¬

renza il capo attraverso il pronoto. A questa età il ca¬

po è completamente nero, e pure oscurato è il pro¬

sterno, compreso il processo prosternale. Più tardi la

colorazione scura si estende al mesosterno, al meta-

sterno e, successivamente, alla fascia centrale dell’ad¬

dome.

Larva di quinta età (Figg. 61 e 66): Larva allunga¬

ta, a lati debolmente convergenti in direzione cauda¬

le a partire dal metatorace; lungo i margini vi sono 16

paia di processi laterali così suddivisi: 4 paia nel pro¬

torace, 2 paia nel meso e 2 nel metatorace, 1 paio in

ciascun segmento addominale. Ogni processo porta

10-15 spinule di lunghezza variabile e diversamente

orientate. La superficie dorsale, escluso il protorace, è

solcata da rugosità piuttosto profonde, più o meno si¬

nuose. Colore interamente giallo paglierino. Lun¬

ghezza totale, esclusa la furca anale e i processi api-

cali, 4,60 mm. Larghezza massima (all’altezza del me¬

tatorace ed esclusi i processi laterali) 2,56 mm. L’ot¬

tavo segmento addominale reca la furca anale, priva

di spinule, lunga 2,70 mm. Il complesso dei frammen¬

ti delle exuvie e residui fecali applicate sulla furca

anale costituisce una struttura del tipo kompakte

Kotmaske, sensu Steinhausen (1950).

Capo subcircolare, ipognato. Fronte lievemente

depressa nel tratto postero-mediano. Ocelli in nume¬

ro di 5 per lato, dei quali quattro disposti internamen¬

te, in linea leggermente arcuata, il quinto, più piccolo,

in posizione latero caudale a detta linea, all’altezza del

terzo ocello. Labrum debolmente chitinizzato, con tre

paia di setole su ciascun lato e incavo mediano poco

accentuato, a fondo rettilineo e lati debolmente ango¬

losi. Antenne bisegmentate, con vari processi senso¬

riali all’apice, di cui uno maggiore in forma di papilla

debolmente conica. Clipeo trasverso, circa 5 volte più

largo che lungo. Mandibole con tre denti apicali.

Torace lungo circa 0,75 volte l’addome. Superficie

del protorace con vari solchi e rughe, più marcati la¬

teralmente. Scudo protoracico poco evidente, forma¬

to da due aree circolari, lievemente depresse, a fondo

rugoso portante qualche corta setola. Tali aree risul¬

tano separate da una regione mediana rilevata, di su¬

perficie più uniforme, con circa 20 setole spiniformi,

le maggiori lunghe fino a 0,1 mm, prevalentemente

disposte lungo il bordo interno delle aree circolari.

Alla base della quarta spina protoracica vi è lo spira-

colo anteriore, in una piccola area subtriangolare se¬

parata dal corpo del protorace da un solco obliquo.

Mesotorace poco meno di quattro volte più largo che

lungo, dorsalmente diviso in pre- e post-mesotergite

da una linea sinuosa. Metatorace quasi cinque volte

più largo che lungo.

Figg. 61-62 - Cassida subreticulata : larva al quinto stadio (61) e

pupa (62).

I CRISOMELIDI (COLEOPTERA CHRYSOMELIDAE) DEL MONTE BARRO (ITALIA, LOMBARDIA, LECCO)

215

Addome con tergiti divisi in pre- e post-tergite da

una linea arcuata, più marcata lateralmente. Superfi¬

cie con numerose piccole setole a disposizione più o

meno uniforme. Ai lati dei primi sette pretergiti si

trova una coppia di spiracoli addominali, a peritrema

molto saliente.

Pupa (Figg. 62 e 66): Lunghezza 4,77 mm. Lar¬

ghezza 2,98 mm. Colore interamente giallo paglieri¬

no, privo di zone pigmentate.

Superficie dorsale opaca, con microrugosità pre¬

valentemente disposta in senso trasversale.

Pronoto circa 3 volte più corto della lunghezza to¬

tale del corpo; subpentagonale, convesso; area poste¬

riore più saliente della anteriore. Superficie opaca,

con microrugosità variamente disposta; qualche bre¬

vissima setola, visibile solo a forte ingrandimento, è

presente soprattutto nella metà posteriore. Margine

anterolaterale con circa 40 spine di varia lunghezza e

per lo più semplici; solo due coppie centro-laterali,

più lunghe, portano qualche spinula. Al centro del

margine anteriore vi è una intaccatura subtriangola¬

re, dalla quale si diparte una linea liscia, sublucida e

leggermente rilevata che attraversa longitudinalmen¬

te i due terzi anteriori del pronoto ed è interrotta da

una areola trasversale, in forma di una fascia liscia e

male delimitata, che costituisce con la linea longitu¬

dinale una struttura a croce debolmente rilevata.

Margine posteriore bisinuato, con due marcate intac¬

cature sublaterali.

Meso e metatorace privi di particolari strutture ad

esclusione degli astucci alari i quali, ruotati lateral¬

mente e ventralmente, sono poco visibili dall’alto.

Tergiti addominali convessi, con linea mediana ri¬

levata quasi in forma di carena; inoltre un solco bre¬

vemente inciso, più evidente nei segmenti addomina¬

li anteriori, si stacca circa a metà del margine ante¬

riore di ciascun emitergite, raggiungendone la linea

mediana. Primi cinque segmenti addominali ciascuno

con una coppia di processi laterali in forma di lamine

appiattite in senso dorsoventrale. Gli anteriori più

ampi, i successivi progressivamente decrescenti in

senso caudale. Ciascun processo reca lungo il margi¬

ne laterale una serie di 7-9 spinule, la apicale sensi¬

bilmente più lunga. Alla base di ciascun processo,

spostato verso il margine anteriore del tergite, si tro¬

va uno spiracolo, con peritrema fortemente saliente.

Gli ultimi tre segmenti addominali recano coppie di

processi laterali spiniformi, orientati in direzione cau¬

dale, solo in parte visibili dall’alto perchè inseriti

piuttosto ventralmente.

Fronte marcatamente incavata. Antenne orientate

obliquamente verso l’estremità caudale, con segmen¬

ti apicali prossimi alla articolazione femoro-tibiale

anteriore. Astucci alari sottoposti al piano di giacitu¬

ra delle zampe anteriori e medie, ma in parte rico¬

prenti le posteriori, delle quali risultano ben visibili

solo tibie e tarsi.

Considerazioni biogeografiche

Le categorie corologiche indicate nel testo sono

state individuate secondo i criteri proposti da Vigna

Taglianti et al. (1992).

Dall’analisi dei singoli corotipi (Figg. 63-64) emer¬

ge una dominanza di elementi ad ampia distribuzio¬

ne nella regione Paleartica. È però cospiqua anche la

presenza di taxa a gravitazione europea, ivi compre¬

so un numero non indifferente di elementi Sudeuro¬

pei (17,88% del totale), mentre i taxa riferibili a co¬

rotipi Mediterranei rappresentano una percentuale

molto modesta (1,3%) delle specie raccolte. È stata

esclusa Leptinotarsa decemlineata in quanto zoogeo-

graficamente estranea alla fauna paleartica.

ASE f . li - „J-,- . .. „„ . . A ■ - . . - f 33

SEU *>■»---« • • -gp 27

PAL pta*as&.;. ■„*,>, Sl , -- ^ 19

EUR 15

TUE . . - . . -0 14

S'E 12

EUM K 10

TEM F ****4*imis*smj 7

CEU 5

0LA 3

CENI f 1 3

WME Fp 1

MED frP 1

CAE fr? 1

0 5 10 15 20 25 30 35

Fig. 63 - Spettro corologico delle specie raccolte.

Medit.

1,32%

Fig. 64 - Corotipi raggruppati per categorie sintetiche (Vigna Ta¬

glianti et al., 1991).

Fenologia

Dalle date di raccolta delle singole specie abbia¬

mo ricavato la Fig. 65, che rappresenta un semplice

quadro orientativo dell’abbondanza delle specie nel¬

le raccolte condotte in diversi periodi dell’anno, sen¬

za la pretesa di fornire una informazione completa

sulla fenologia delle specie.

Per ogni specie sono indicate le stazioni di presen¬

za (st), e per ogni stazione, il numero complessivo de¬

gli esemplari raccolti (n) e il numero medio di esem¬

plari raccolti per uscita (F), per il cui calcolo si è te¬

nuto conto solo delle uscite effettuate in periodi in

cui la specie è risultata presente.

Le altezze degli elementi di ogni istogramma sono

determinate, per ogni specie e per ogni stazione, dal

rapporto tra il numero medio di esemplari raccolto

nelle uscite effettuate in un particolare periodo e il

numero medio (F) di esemplari raccolto nelle uscite

effettuate in tutto l’arco dell’anno. In questo modo si

ottiene, per ciascun periodo, una misura dell’abbon¬

danza relativa della specie. Per facilitare la lettura di

questo dato, i rapporti calcolati sono stati raggruppa¬

ti in cinque classi di frequenza (<0, 5; 0,51-1; 1,01-1,50;

216

CARLO LEONARDI & DAVIDE SASSI

1,51-2; >2), corrispondenti a cinque diverse altezze

degli istogrammi.

Abbreviazioni usate nel testo

MM: Museo di Storia Naturale di Milano; CZ: col¬

lezione Zoia; Le: lunghezza (distanza apice - base)

dell’elitra; Lp: lunghezza del pronoto; lp: larghezza

del pronoto; Lt: lunghezza della tibia posteriore in

completa distensione; Ld: lunghezza della porzione

tibiale posteriore all’inserzione del metatarso; (...) m

valore medio di .

Ringraziamenti

Ringraziamo la Dr.ssa Nicole Berti, del Museo di

Storia Naturale di Parigi, per il prestito dei tipi di

Longitarsus anacardius , e gli amici Serge Doguet, per

il prestito di esemplari algerini di L. anacardius , Da¬

vid Furth, per il dono di esemplari di Longitarsus

truncatellus al Museo di Storia Naturale di Milano, e

Stefano Zoia, per il dono di esemplari di Crepidode-

ra peloponnesiaca al Museo di Storia Naturale di Mi¬

lano. Un particolare ringraziamento va inoltre al Dr.

Giuseppe Panzeri e al Dr. Mauro Villa, rispettiva¬

mente Presidente e Direttore del Consorzio Parco

Monte Barro, per l’aiuto fornitoci durante le nostre

ricerche.

I CRISOMELIDI (COLEOPTERA CHRYSOMELIDAE) DEL MONTE BARRO (ITALIA, LOMBARDIA, LECCO)

217

marzo aprile maggio giugno luglio agosto settembre ottobre novembre

14-30 1-15 16-30 1-15 16-30 1-15 16-30 1-15 16-30 1-15 16-30 1-15 16-30 1-15 16-30 1-15 16-30

218

CARLO LEONARDI & DAVIDE SASSI

marzo aprile maggio

giugno luglio agosto settembre ottobre novembre

1-15 16-30 1-15 16-30 1-15 16-30 1-15 16-30 1-15 16-30 1-15 16-30

219

220

CARLO LEONARDI & DAVIDE SASSI

Specie

Lup. flavipes

Lup. leonardii

Phyllotr. vittula

Phyllotr. nemorum

Phyllotr. striolata

Phyllotr. ochripes

Phyllotr. aerea

Aphth. cyparissiae

Aphth. lutescens

Aphth. pygmaea

Aphth. venustula

Aphth. coerulea

Aphth. herbigrada

Aphth. ovata

Aphth. atrovirens

Longit. pellucidus

marzo aprile maggio giugno luglio agosto settembre ottobre novembre

1-15 16-30 1-15 16-30 1-15 16-30 1-15 16-30 1-15 16-30

Longit. succineus

I CRISOMELIDI (COLEOPTERA CHRY SOMELID AE) DEL MONTE BARRO (ITALIA. LOMBARDIA. LECCO)

giugno luglio agosto settembre ottobre novembre

1-15 16-30 1-15 16-30 1-15 16-30 1-15 16-30 1-15 16-30 1-15 16-30

inni n i i 1 1 i imi

222

CARLO LEONARDI & DAVIDE SASSI

I CRISOMELIDI (COLEOPTERA CHRY SOMELID AE) DEL MONTE BARRO (ITALIA, LOMBARDIA, LECCO)

223

Specie

Chaetocn. conducta

Chaetocn. confusa

Chaetocn. arida

Chaetocn. hortensis

Sphaerod. testac.

Sphaerod. rubidum

Argopus ahrensi

Dibolia foersteri

Dibolia cryptoceph.

Psylliodes affinis

Psylliodes napi

Psylliodes toelgi

Psylliodes brisouti

Psylliodes cupreus

Psylliodes instabilis

Psylliodes dulcam.

Cassida subferrug.

Cassida viridis

Cassida vibex

marzo aprile maggio giugno

luglio agosto settembre ottobre novembre

1-15 16-30 1-15 16-30 1-15 16-30 1-15 16-30 1-15 16-30

III III I DII

224

CARLO LEONARDI & DAVIDE SASSI

aprile maggio giugno luglio

1-15 16-30 1-15 16-30 1-15 16-30 1-15 16-30

agosto settembre ottobre novembre

1-15 16-30 1-15 16-30 1-15 16-30 1-15 16-30

Fig. 65 - Tabella fenologica delle specie raccolte nelle stazioni 1-9.

I CRISOMELIDI (COLEOPTERA CHRYSOMELIDAE) DEL MONTE BARRO (ITALIA. LOMBARDIA. LECCO)

225

a

Fig. 66 - Cassida subreticulata. a) larva di quinta età con esuvie e residui fecali sulla furca anale; b) larva con furca anale par¬

zialmente ribaltata sul dorso; c) larve coperte daH’ombrello fecale; d) pupa; e) adulti neosfarfallati; f) adulti in accoppia¬

mento.

226

CARLO LEONARDI & DAVIDE SASSI

Fig. 67 - Stazioni di raccolta, a) staz. 1 (in loc. Piani di Barra); b) staz. 2 (in loc. Piani di Barra); c) staz. 5 (Pian Sciresa); d)

staz. 6 (superfici prative lungo il sentiero della «cresta occidentale»); e) staz. 7 (in Val di Faè); f) staz. 8 (in Val di Faè).

I CRISOMELIDI (COLEOPTERA CHRYSOMELIDAE) DEL MONTE BARRO (ITALIA, LOMBARDIA. LECCO)

227

BIBLIOGRAFIA

Balachowsky A.S., 1963 - Entomologie appliquée a l'agriculture,

tome I, Coleopteres, 2° volume Phytophagoidea (suite et fin)

: 566-1391 (567-873).

Baranowski R.. 1980 - Interessanta skalbaggsfynd 5 (Coleopte-

ra). End. Tidskr ; Lund, 101: 99-106.

Bedel., 1989-1901- Faune des Coléoptères du Bassin de la Seine.

Soc. ent. Fr., 4: 1-423.

Begon M., Harper J.L. & Townsend C.R., 1989 - Ecologia. Indi¬

vidui. popolazioni, comunità. Zanichelli , Bologna: I-XIII + 1-

854.

Berger W. H. & Parker F.L., 1970 - Diversity of Planktonic Fo-

raminifera in Deep-Sea Sediments. Science , 168: 1345-1347.

Berti N. & Rapilly M., 1976 - Faune d’Iran. Liste d’especes et re-

vision du Genre Lilioceris Reitter (Col, Chrysomelidae). Ann.

Soc. ent. Fr. (N. S.), 12 (I): 31-73.

Biondi M., 1990 - Elenco commentato dei Crisomelidi Alticini

della fauna italiana (Coleoptera). Fragni. Entomol., Roma, 22

(1): 109-183.

Biondi M„ Daccordi M., Regalin R„ & Zampetti M., 1994 -

Coleoptera Polyphaga XV (Chrysomelidae, Bruchidae). In

Minelli A., Ruffo S. & La Posta S. (eds.). Checklist delle specie

della fauna italiana, 60. Calderini , Bologna, 1-34.

Bourdonné J-C. & Doguet S„ 1991 - Données sur la biosysté-

matique des Chrysolina 1. s. (Coleoptera: Chrysomelidae:

Chrysomelinae). Ànn. Soc. ent. Fr. (N. S.), 27 (I): 29-64.

Burlini M., 1955 - Revisione dei Cryptocephalus italiani e della

maggior parte delle specie di Europa (Col. Chrysomelidae).

Meni Soc. ent. It., Genova, 34: 5- 287.

Corti M. & Loy A., 1985 - Morfometria multivariata e variazione

geografica. Biogeographia, 11: 91-113.

Doguet S., 1993 - Réhabilitation de Longitarsus helvolus Kut-

schera 1863 , espece distincte de Longitarsus membranaceus

(Foudras 1860) (Col. Chrysomelidae). Ent. gali. 4(2/3): 45-46.

Doguet S., 1994 - Coléoptères Chrysomelidae, voi 2: Alticinae.

Faune de France, 80: 1-696.

Doguet S., Bastazo G., Bergeal M„ Vela J. M., 1996 - Contri-

bution à l’étude des Chrysomelidae d’Andalousie (Coleopte¬

ra). Nuov. Revue Ent. (N.S.), 13 (4): 315-323.

Gruev B. & Tomov B., 1984 - Coleoptera Chrysomelidae Part 1:

Orsodacninae, Zeugophorinae, Donaciiinae, Criocerinae, Cly-

trinae, Cryptocephalinae, Lamprosomatinae, Eumolpinae.

Fauna Bilgariae. Acad. Scient. Bulg., Sofia, 13: 1-220.

Gruev B. & Tomov V, 1986 - Coleoptera, Chrysomelidae Part 2:

Chrysomelinae, Galerucinae, Alticinae, Hispinae, Cassidinae.

Fauna Bulgariae. Acad. Scient. Bulg., Sofia, 16: 1-387.

Heikertinger F, 1910 - Chalcoides aurata nov. var. peloponnesia¬

ca Heikert... Verh. zool. hot. Ges. Wien, 60: (54).

Kippenberg H., 1994 - 88. Familie:Chrysomelidae in Ergànzungen

und Berichtigungen zu Freude-Harde-Lohse «Die Kàfer Mit-

teleuropas». Goecke & Evers, Krefeld. Band 9 (1966). 3 Sup-

plementband.: 17-142.

Konstantinov A.S. & Vandenberg N.J., 1996 - Handbook of Pa-

learctic Flea Beetles (Coleoptera: Chrysomehidae: Alticinae).

Contrib. on Entom., International, Gainesville: 237-439.

■ Lambshead P.J.D., Platt H.M. & Shaw K.M., 1983 - The detec¬

tion of differences among assemblages of marine benthic spe-

cies based on an assessment of dominance and diversity.

Journ. of Nat. Hist., London, 17: 859-874.

Leonardi C., 1971 - Considerazioni sulle Psylliodes del gruppo

napi e descrizione di una nuova specie (Coleoptera Chryso¬

melidae). Atti Soc. ital. Sci. nat. Mus. civ. Stor. nat., Milano, 112:

485-533.

Lison L., 1961 - Statistica applicata alla biologia sperimentale. Ca¬

sa Editrice Ambrosiana, Milano: 1-381.

Lopatin I.K., 1977 - Zhuki-Listoedy (Chrysomelidae) Srednei

Azii i Kazakhstana. Nauka, Leningrad: 1-269.

Medvedev L.N., 1982 - Chrysomelidae of thè Mongolian People’s

Republic: identification key. Nauka, Moscow: 1-302.

Medvedev L.N., 1986 - Chrysomelidae in «Identification key of

insects of thè Sovietic Far East». Nauka, S.Petersburg: 533-

602.

Mohr K.-H., 1966 - Chrysomelidae in «Die Kàfer Mitteleuropas»,

Band 9. Goecke & Evers, Krefeld: 95-299. Phànologie. Centro

Sperim. Agricoltura e Foreste, Trieste: 1-686.

Muller G., 1951-1953 - I Coleotteri della Venezia Giulia. II.Co-

leoptera Phytophaga. La Edit. Libraria, Trieste: 225-685.

Perner J., 1996 - Zur Phànologie und Biotopbindung ausgewàhl-

ter Flohkàfer (Coleoptera, Chrysomelidae, Alticinae). Verh.

des 14. Intern. Symposiums iiber Entomofaunistik in Mitteleu-

ropa, Miinchen: 247-260.

Pesarini E, 1986 - Imenotteri Sinfiti del Piano Pedemontano in

Lombardia IL Note ecologiche. Memorie Soc. ent. ital., Geno¬

va, 64: 73-92.

Ruffo S., 1938 - Studi sui Crisomelidi. Boll. Ist. ent. Univ. Bologna,

10: 178-222 + 3 tavv.

Steinhausen W., 1950 - Vergleichende Morphologie, Biologie und

Òkologie der Entwicklungsstadien der in Niedersachsen hei-

mischen Schildkàfer (Cassidinae Chrysomelidae Coleoptera)

und deren Bedeutung fiir die Landwirtschaft. Diss. Tech. Ho-

chsch. Carolo-Wilh. Braunschweig : 69 pp, 8 pi..

Suffrian E., 1847 - Revision der Europàischen Arten der Gat-

tung Cryptocephalus. Linn. Ent., 2: 1-194.

Vigna Taglianti A., Audisio P.A., Belfiore C., Biondi M., Bo¬

logna M. A., Carpaneto G. M., De Biase A., De Felici S.,

Piattella E., Racheli T., Zapparoli M. & Zoia S. - 1992 -

Riflessioni i gruppo sui corotipi fondamentali della fauna W-

paleartica ed in particolare italiana. Biogeographia, 16: 159-

179.

Warchalowski A., 1969 - lìdie Systematik und Verbreitung eini-

ger westpalàarktischer Longitarsus- Arten (Coleoptera Chry¬

somelidae). Polskie Pismo Entom., Wroclaw, 39 (3): 515-527.

Warchalowski A., 1978 - Klucze do Oznaczania owadow Polski,

Cz. XIX, Ze. 94c: Stonkowate Chrysomelidae, Podrodziny

Halticinae, Hispinae, Cassidinae. Polskie Towarz. Entom.,

Warszawa, nr. 105 serii kluczy: 1-157.

Warchalowski A., 1991 - Chrysomelidae (Insecta Coleoptera)

Part IL (podrodziny: Clythrinae i Cryptocephalinae). Fauna

Polski. Tom 13, Warszawa:l-347.

Weise J., 1893 - Coleoptera. In: Erichson W.F. (Nicolaische Ver-

lags-Buchhandlung), Naturgeschichte der Insekten Deutsch-

lands, 1, 6: 1-1161.

Carlo Leonardi: Museo Civico di Storia Naturale, Corso Venezia 55, 20121 Milano

Davide SassùVia San Rocco 17, 22030 Castelmarte

Studi geobotanici ed entomofaunistici nel Parco Regionale del Monte Barro

Memorie della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano

Volume XXVII - Fascicolo II - 1997

..

Carlo Pesarini

I Curculionidi in senso lato (Coleoptera Attelabidae,

Apionidae e Curculionidae) del Monte Barro

(Italia, Lombardia, Lecco)

Riassunto - Col presente lavoro sono forniti i dati relativi alla popolazione curculionidica del Monte Barro, come risul¬

tato di una ricerca condotta negli anni 1989-1992 dal Museo di Storia Naturale di Milano. Le raccolte sono state effettuate

prevalentemente in 9 stazioni prative. Vengono analizzate le caratteristiche biogeografiche della popolazione curculionidi¬

ca, 9 specie ( Nanophyes annulatus, Apion armatum, A. flavimanum, A. filirostre, A. ebeninum, Thamiocolus signatus, Coelio¬

des dryados, Miarus distinctus, Miarus micros) sono segnalate come nuove per la Lombardia e si ribadisce la presenza in Ita¬

lia di Polydrusus corruscus.

Abstract - Weevils (Coleoptera Attelabidae, Apionidae and Curculionidae) from Monte Barro (Italy, Lombardy, Lec¬

co).

In thè present work data concerning thè weevil-fauna of Monte Barro are given, as result of a research carried out by

thè Naturai History Museum of Milano in thè years 1989-1992. Samplings have been largely addressed to thè study of mea-

dows and 9 sampling sites have been chiefly investigated. The biogegraphic pattern of thè weevil-population is analyzed, 9

species ( Nanophyes annulatus, Apion armatum, A. flavimanum, A. filirostre, A. ebeninum, Thamiocolus signatus, Coeliodes

dryados, Miarus distinctus, Miarus micros ) are recorded for thè first time from Lombardy, and thè presence in Italy of Poly¬

drusus corruscus is confirmed.

Key words: Monte Barro, Curculionidae, geographic distribution.

Le ricerche effettuate dal Museo di Storia Natura¬

le di Milano nel corso di quattro campagne annuali di

raccolta hanno fornito un quadro assai ampio e, nei

limiti del possibile, verosimilmente completo della

fauna curculionidica del M. Barro. Tale risultato è sta¬

lo possibile grazie anche agli elementi aggiuntivi che

hanno permesso di integrare la già ricca massa di da-

}ti prodotta dalle ricerche di Davide Sassi e Carlo

Leonardi. Tali elementi sono stati forniti dal lavoro

csvolto, nell’ambito di una tesi di laurea da me coordi¬

nata, dalla Dr.ssa Laura Bonini.

Osservazioni sulle stazioni di raccolta

Le raccolte sono state effettuate prevalentemente

in 9 stazioni prative, le cui caratteristiche ambientali

sono state ampiamente analizzate nel contributo di

Banfi, Galasso & Sassi, in questo stesso volume. Ul¬

teriori stazioni di raccolta, ispezionate soprattutto da

Laura Bonini e da Davide Sassi, sono state riunite,

nel quadro d’insieme, in una sorta di stazione cumu¬

lativa indicata con il numero 10.

Qui di seguito è data una breve descrizione delle

■stazioni 1-9 e sono indicate le specie esclusive (speci¬

ficità) per ciascuna stazione; le specie contrassegnate

da un asterisco pur non essendo state rinvenute in

nessun’altra fra le nove stazioni considerate risultano

presenti in uno o più dei biotopi riuniti al numero 10.

Stazione 1: Località Piani di Barra, 610 m, esp. W,

■ .

interessata da scavi archeologici (Grande Edificio). È

caratterizzata da una consistente presenza di prato

falciabile che indica una attività di foraggio residua.

Specificità: Lixus bardanae , Dorytomus taenicitus.

Stazione 2: Località Piani di Barra, 600 m, esp. W,

interessata da scavi archeologici (Edificio II). Si trat¬

ta di una prateria in cui è stata abbandonata la ge¬

stione a foraggio, vi è quindi presente un leggero

mantello. Specificità: Attelabus nitens*, Thamiocolus

signatus, Coeliodes dryados, Tychius longicollis *,

Rhynchaenus signi fer*.

Stazione 3: Conca prativa a monte del Monumento

dell’Alpino, 630 m, esp. W. Vi si nota la convivenza di

elementi di prateria, elementi di prato falciabile ed ele¬

menti di disturbo marginale. Specificità: Coenorhinus

aeneovirens*, Apion confluens, Apion flavimanum,

Apion oblivium, Apion holosericeum, Phyllobius etru-

scus*, Ceuthorhynchus cochleariae, Cionus thapsus.

Stazione 4: Località S. Michele, pendio in prossi¬

mità del sentiero per Pian Sciresa, 325 m, esp. E. Su

una base di Mesobromion è in pieno sviluppo il pra¬

to falciabile, che qui presenta il carattere oligo-meso-

trofico. Specificità: Otiorhynchus ovatus.

Stazione 5: Località Pian Sciresa, 435 m, esp. NE.

È un prato arido con montarozzi residui a brughiera;

per il resto il livello di base è costituito da prateria a

Brachypodium rupestre ssp. caespitosum. Specificità:

Apion subulatum, Sitona suturalis, Hypera venusta,

Micrelus ericae, Tychius polylineatus.

Stazione 6: Superfici prative lungo il sentiero del¬

la «Cresta occidentale», che dall’edificio dell’ex sana-

230

CARLO PESARINI

torio sale alla vetta, 750 m, esp. S. Si tratta di una pra¬

teria con parziale affioramento roccioso, fortemente

cespugliata e in via di chiusura, con forte influsso del-

relemento prenemorale (tendenza a un Quercetum

pubescenti s. 1.) Specificità: Apion aeneomicans ,

Apion cerdo, Apion opeticum , Magdalis exarata *, Ty-

chius junceus, Miarus rnicros.

Stazione 7: Località Fornaci Villa, in prossimità

deH'impluvio della Val Faè, 275 m, esp. NW. È una su¬

perficie prativa terrazzata all’interno del bosco meso¬

frio, molto simile a quella della stazione 8 ma più

aperta e con qualche elemento in più di Mesobro-

mion. Specificità: Apion rufirostre, Apion nigritarse,

Apion ebeninum, Polydrusus atomarius, Polydrusus

corruscus, Hypera nigrirostris , Hypera postica*.

Stazione 8: Località Fornaci Villa, in prossimità

deH’impluvio della Val Faè, 305 m, esp. NW. È un pra¬

to terrazzato irregolarmente gestito e contornato da

un bosco con notevoli contrassegni mesofili. Specifi¬

cità: Leiosoma concinnimi, Trichosirocalus rufulus.

Stazione 9: Località Ca’ di Sala, 226 m, sulla riva

settentrionale del bacino di Oggiono del Lago di An¬

none. Vi si evidenziano tre aspetti essenziali: 1) il can¬

neto, con accenni di aggruppamento a Iris pseudoa-

corus , elementi di magnocariceto e residui di bosca¬

glia ripariale 2) prato umido oligotrofico ( Molinion

coeruleae ); 3) vegetazione erbacea perenne e disor¬

ganizzata al margine superiore della stazione. Specifi¬

cità: Nanophyes marmoratus, Nanophyes annulatus,

Lepyrus capucinus, Hylobius transversovittatus, Rhi-

noncus perpendicularis, Pelenomus comari, Tapinotus

sellatus, Limnobaris t-album, Tychius meliloti, Dory-

tomus rufatus, Notaris scirpi, Rhynchaenus salicis.

Elenco delle specie raccolte

In tale elenco si è seguito l’ordine adottato nel re¬

cente lavoro di Abbazzi & Osella (1992) sulla curcu-

lionidofauna italiana, includendovi le famiglie Attela-

bidae, Apionidae e Curculionidae. Di tale lavoro so¬

no state seguite nel complesso anche le scelte siste¬

matiche, con l’unica eccezione di rilievo costituita dal

mantenimento del senso tradizionale del genere

Apion , che nel citato lavoro viene suddiviso in 39 ge¬

neri distinti, ai quali qui viene assegnato invece il ran¬

go più tradizionale (e che personalmente ritengo più

adeguato nella stragrande maggioranza dei casi) di

semplici sottogeneri.

Delle specie censite, 9 risultano nuove per la fau¬

na lombarda.

Lasiorhynchites (Coccigorhynchites) sericeus (Herbst)

Presenza in Italia: tutta Italia e Sicilia.

Piante ospiti: diverse specie del genere Quercus.

Due reperti sul versante meridionale verso Sella

d. Pila: 13. VI. 1990, lg. Bonini (su Quercus ); 30.V.1990,

lg. Sassi (su Quercus).

Coenorliinus (Pselaphorhynchites) nanus (Paykull)

Corotipo: Sibirico-Europeo (SIE)

Presenza in Italia: Liguria, Piemonte, Lombardia,

Veneto, Trentino-Alto Adige, Friuli-Venezia Giulia,

Emilia-Romagna, Toscana, Campania, Basilicata, Ca¬

labria.

Piante ospiti: in prevalenza salici ( Salix ), ma anche

Betula e Alnus.

Due esemplari raccolti a giugno nelle staz. 2 e 6.

Coenorhinus ( Pselaphorhynchites ) tomentosus (Gyl-

lenhal)

Corotipo: Sibirico-Europeo (SIE)

Presenza in Italia: tutta Italia, Sicilia.

Piante ospiti: in prevalenza salici (Salix), più di ra¬

do Populus.

Due esemplari raccolti a maggio e giugno nelle

staz. 2, 4, 5 e 6.

Coenorhinus (s.str.) germanicus (Herbst)

Corotipo: Sibirico-Europeo (SIE)

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: diverse Salicacee e Rosacee.

Svariati reperti singoli in maggio e giugno nelle

stazioni 1, 2, 3, 5, 6, in un prato attiguo alla stazione 4,

presso la stazione di osservazione ornitologica e sot¬

to la vetta.

Coenorhinus (s.str.) aeneovirens (Marsham)

Corotipo: Europeo (EUR)

Presenza in Italia: Liguria, Piemonte, Lombardia,

Veneto, Trentino -Alto Adige, Friuli-Venezia Giulia,

Emilia-Romagna, Toscana, Umbria, Marche, Lazio,

Abruzzo, Campania, Puglie.

Piante ospiti : in prevalenza querce (Quercus), ma

anche Rosacee.

Due esemplari raccolti a maggio nella staz. 3 e in

un prato della vai Faè vicino alla stazione 7.

Coenorhinus (s.str.) aequatus (Linneo)

Corotipo: Europeo (EUR)

Presenza in Italia: tutta Italia.

Piante ospiti: diverse Rosacee arboree e arbustive.

Due reperti (24.IV.1990, lg. Sassi, boschi della vai

Faè nei pressi della staz. 7; 13.VI.1990, lg. Bonini, a

sud della vetta sopra la stazione di osservazione orni¬

tologica)

Rhynchites (Involvulus) aethiops (Bach)

Corotipo: Europeo (EUR)

Presenza in Italia: tutta Italia, Sicilia.

Piante ospiti: Helianthemum nummularium.

Rinvenuto, spesso in numerosissimi esemplari,

sulla sua pianta ospite, nelle stazioni 3, 4, 5 e 6, sopra

la stazione di osservazione ornitologica e presso la

vetta, fra maggio e luglio, con un marcato picco di

maggiore abbondanza in giugno.

Apoderus coryli (Linneo)

Corotipo: Sibirico-Europeo (SIE)

Presenza in Italia: tutta Italia.

Piante ospiti: in prevalenza nocciolo (Corylus

avellana), ma anche Alnus e Betula.

Rinvenuto svariate volte, ma in pochi esemplari,

nelle stazioni 1, 2, 4, 5, 6 e sul versante meridionale,

lungo un sentiero che dall’eremo conduce alla sella

della Pila, fra maggio e luglio, con maggiore frequen¬

za in maggio.

Attelabus nitens (Scopoli)

Corotipo: Sibirico-Europeo (SIE)

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: in prevalenza querce (Quercus), ma

anche Castanea.

Un reperto nella stazione 2 (24.6.1990, lg. Sassi) e

uno sul versante meridionale, lungo un sentiero che

dall’eremo conduce alla Sella della Pila (30. V. 1990,

lg. Sassi).

I CURCULIONIDI IN SENSO LATO (COLEOPTERA ATTELABIDAE. APIONIDAE E CURCULIONIDAE) DEL MONTE BARRO

231

Nanophyes annulatus Aragona

Corotipo: Mediterraneo (MED)

Presenza in Italia: Liguria, Piemonte, Veneto, Tren¬

tino-Alto Adige, Friuli-Venezia Giulia, Emilia-Roma¬

gna, Toscana, Lazio, Abruzzo, Campania, Calabria, Si¬

cilia. La specie risulta nuova per la Lombardia.

Piante ospiti: Lythrum salicaria.

Due soli esemplari provenienti dalla staz. 9, rac¬

colti il 25.V.1990 e il 6.VII.1990.

Nanophyes marmoratus (Goeze)

Corotipo: Sibirico-Europeo (SIE)

Presenza in Italia: tutta Italia.

Piante ospiti: Lythrum salicaria.

Numerosi esemplari provenienti dalla staz. 9, rac¬

colti il 24.V.89, il 16.V.1990 ed il 15.VI.1990.

Apion (Ceratapion) armatum Gerstàcker

Corotipo: Centroeuropeo (CEU)

Presenza in Italia: Liguria, Piemonte, Veneto, Friu¬

li-Venezia Giulia, Lazio, Abruzzo, Campania, Cala¬

bria. La specie risulta nuova per la Lombardia.

Piante ospiti: Centaurea spp.

Numerosi esemplari provenienti dalle stazioni 2,4,

5 e 7 e sul versante meridionale, ai margini di un sen¬

tiero che dall’eremo va alla Sella della Pila, raccolti fra

fine aprile (25. IV) e oltre metà settembre (20.IX).

Apion ( Ceratapion ) onopordi Kirby

Corotipo: Centroasiatico-Europeo (CAE)

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: Asteraceae della tribù Cynareae.

Particolarmente abbondante nella staz. 9, ma rin¬

venuto anche nelle staz. 1, 2, 3, 4, 5, 8, ai margini di un

sentiero a nord-ovest dei Piani di Barra e in un prato

presso Camporeso da fine marzo a settembre.

Apion (Diplapion) confluens Kirby

Corotipo: Europeo-Mediterraneo (EUM)

Presenza in Italia: Piemonte, Val d’Aosta, Lom¬

bardia, Trentino-Alto Adige, Friuli-Venezia Giulia,

Toscana, Umbria, Lazio, Puglia, Basilicata, Calabria,

Sicilia, Sardegna.

Piante ospiti: specie dei generi Matricaria e Anthemis.

Due reperti in staz. 3 (9.V.1990, lg. Sassi;

16.V.1991, leg. Bonini).

Apion (Aspidapion) aeneum (Fabricius)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie dei generi Malva e Althaea.

Alcuni esemplari raccolti nelle stazioni 1, 2 e 3 in

maggio e giugno.

Apion (Squamapion) atomarium Kirby

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: Italia settentrionale, Toscana,

Abruzzi, Sardegna.

Piante ospiti: specie del genere Thymus.

Alcuni esemplari rinvenuti da maggio a settembre

nelle staz. 3, 4 e 5.

Apion ( Squamapion ) flavimanum Gyllenhal

Corotipo: Europeo (EUR).

Presenza in Italia: Piemonte, Veneto, Trentino- Al¬

to Adige, Friuli-Venezia Giulia, Emilia-Romagna, To¬

scana, Sicilia, Sardegna. La specie risulta nuova per la

Lombardia.

Piante ospiti: specie del genere Mentila.

Un esemplare proveniente dalla staz. 3 (19.V.1991,

lg. Bonini).

Apion ( Squamapion ) minutissimum Rosenhauer

Corotipo: Europeo (EUR).

Presenza in Italia: Liguria, Piemonte, Lombardia,

Veneto, Lazio, Toscana.

Piante ospiti: specie del genere Thymus.

Tre esemplari, raccolti in differenti località e date:

staz. 2, 19.V.1991, lg. Leonardi, staz. 3, 14.III. 1990, lg.

Leonardi, e in un prato della Val Faè prossimo alla

staz. 7, 25.IV.1990, lg. Sassi.

Apion ( Squamapion ) oblivium Schilsky

Corotipo: Europeo (EUR).

Presenza in Italia: Liguria, Piemonte, Lombardia.

Piante ospiti: specie del genere Thymus.

Un solo esemplare raccolto nella staz. 3

(20.IX.1989, lg. Leonardi).

Apion (Taeniapion) urticarium (Herbst)

Corotipo: W-Paleartico (WPA).

Presenza in Italia: tutta Italia, Sicilia.

Piante ospiti: Unica dioica.

Alcuni esemplari raccolti nelle staz. 3, 4 e 9 fra fi¬

ne marzo e metà giugno.

Apion ( Pseudapion ) rufirostre (Fabricius)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: Malva sylvestris e neglecta.

Tre esemplari raccolti nella staz. 7 (V.1992, lg. Sassi).

Apion ( Trichopterapion ) holosericeum Gyllenhal

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: noto di gran parte d’Italia e Sicilia.

Piante ospiti: Carpinus betulus e orientalis.

Alcuni esemplari raccolti nella staz. 3 (19.V.1991,

lg. Bonini).

Apion (Exapion) difficile Herbst

Corotipo: Centroeuropeo (CEU).

Presenza in Italia: Italia settentrionale, Toscana,

Lazio, Abruzzi, Puglia, Calabria.

Piante ospiti: specie del genere Genista.

Svariati esemplari raccolti fra metà maggio e fine

giugno nelle staz. 1, 2, 5 e 6 e ai margini di un sentie¬

ro a nord-ovest dei Piani di Barra.

Apion ( Exapion ) formaneki Wagner

Corotipo: Centroeuropeo (CEU).

Presenza in Italia: Italia settentrionale, Toscana,

Abruzzi, Campania, Puglia, Basilicata.

Piante ospiti: specie dei generi Genista e Cytisus.

Svariati esemplari raccolti in maggio e giugno nelle

staz. 2, 3, 4, 5 e 6, ai margini di un sentiero a nord-ovest

dei Piani di Barra e nei prati sotto la Sella della Pila.

Apion (Protapion) filirostre Kirby

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Liguria, Piemonte, Friuli-Vene¬

zia Giulia, Emilia- Romagna, Toscana, Umbria, Lazio,

Campania. La specie risulta nuova per la Lombardia.

Piante ospiti: specie del genere Medicago.

Due singoli esemplari raccolti nelle stazioni 1 e 7

(rispettivamente il 19.V.1991 ed il 16.V.1990, lg. Leo¬

nardi).

232

CARLO PESARINI

Apion (Protapion) nigritarse Kirby

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie del genere Trifolium.

Un solo esemplare raccolto nella staz. 7

(16.V.1990, lg. Leonardi).

Apion ( Protapion ) fulvipes Geoffroy

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie dei generi Trifolium, Medica-

go e Ononis.

Numerosi esemplari raccolti fra fine aprile e giu¬

gno nelle staz. 1, 2, 3, 4, 5, 6. 7 e 9, in un prato vicino

alla staz. 7 e in un prato vicino a Camporeso.

Apion ( Protapion ) trifolii (Linneo)

Corotipo: Paleartco (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie del genere Trifolium.

Numerosi esemplari raccolti in tutte le stazioni in

maggio e giugno.

Apion ( Protapion ) interj ectum Desbrochers

Corotipo: Mediterraneo (MED).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: prevalentemente Trifolium monta-

num ; indicata anche Ononis repens.

Due singoli esemplari raccolti nelle staz. 2 e 3 (ri¬

spettivamente 19.V.1991 e 20.IX.1989, lg. Leonardi).

Apion (Protapion) apricans Herbst

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: Trifolium pratense.

Svariati esemplari raccolti fra fine aprile e metà

giugno nelle staz. 1-8 e nei boschi della Val Faè.

Apion (Protapion) ononicola Bach

Corotipo: W-Paleartico (WPA).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie del genere Ononis.

Alcuni esemplari raccolti fra metà maggio e giu¬

gno nelle staz. 2 e 6, ai margini di un sentiero che dal-

l’eremo porta alla Sella della Pila e nell’area a nord-

ovest dei Piani di Barra.

Apion (Protapion) assimile Kirby

Corotipo: W-Paleartico (WPA).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie del genere Trifolium.

Numerosi esemplari raccolti da marzo a giugno

nelle staz. 1-9, ai margini di un sentiero a nord-ovest

dei Piani di Barra, in un prato vicino alla staz. 7, in un

prato presso Camporeso e in località S.Michele (in un

prato attiguo alla stazione 4).

Apion (Protapion) difforme Ahrens

Corotipo: W-Mediterraneo (WME).

Presenza in Italia: Liguria, Piemonte, Lombardia,

Veneto, Friuli-Venezia Giulia, Toscana, Umbria, La¬

zio, Basilicata, Sicilia, Sardegna.

Piante ospiti: specie del genere Trifolium.

Alcuni esemplari raccolti nel staz. 2 e 7 e nei bo¬

schi della Val Faè da fine maggio a metà giugno.

Apion (Protapion) varipes Germar

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie del genere Trifolium.

Alcuni esemplari raccolti nelle staz. 1, 3, 5 e 6 da

maggio a settembre.

Apion (Helianthemapion) aciculare Germar

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: Liguria, Lombardia, Veneto,

Trentino-Alto Adige, Friuli-Venezia Giulia, Emilia-

Romagna, Toscana, Abruzzi.

Piante ospiti: specie dei generi Helianthemum, Tu¬

berà ria e Fumaria.

Numerosi esemplari raccolti da fine aprile a fine

maggio nelle staz. 1, 2 e 5, a Camporeso, in un prato

della Val Faè vicino alla staz. 7 e sul versante meri¬

dionale, ai margini di un sentiero che dall’eremo con¬

duce alla Sella della Pila.

Apion (Pseudostenapion) simum Germar

Corotipo. Europeo-Mediterraneo (EUM)

Presenza in Italia: Piemonte, Lombardia, Trenti¬

no-Alto Adige, Friuli-Venezia Giulia, Toscana, Mar¬

che, Lazio, Abruzzi, Campania, Basilicata, Sicilia.

Piante ospiti: specie del genere Hypericum.

Alcuni esemplari nelle stazioni 2 e 5 in maggio.

Apion (Perapion) curtirostre Germar

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie del genere Rumex.

Numerosi esemplari raccolti nelle staz. 1, 2, 4 e 5 e

in un prato attiguo alla staz. 4, fra fine marzo e inizio

luglio.

Apion (Perapion) violaceum Kirby

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie del genere Rumex.

Alcuni esemplari raccolti nelle staz. 1, 2, 4 e 5, e in

località S.Michele (in un prato attiguo alla stazione 4)

da fine marzo a inizio giugno.

Apion (s.str.) cruentatum Walton

Corotipo: Europeo (EUR).

Presenza in Italia: Piemonte, Lombardia, Veneto,

Trentino- Alto Adige, Friuli-Venezia Giulia, Toscana,

Campania, Puglia, Calabria, Sicilia, Sardegna.

Piante ospiti: specie del genere Rumex.

Alcuni esemplari raccolti nelle staz. 2, 3, 4, 5, 7, 8 e

in località S.Michele (in un prato attiguo alla stazione

4) da fine marzo a settembre.

Apion (Catapion) seniculus Kirby

Corotipo: W-Paleartico (WPA).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: in prevalenza specie del genere

Trifolium ; vi sono però anche indicazioni relative ai

generi Medicago, Ononis, Vicia e Melilotus.

Numerosi esemplari raccolti quasi ovunque da

marzo a settembre.

Apion (Trichapion) simile Kirby

Corotipo: Paleartico (PAL).

Presenza in Italia: Italia settentrionale.

Piante ospiti: Betula penduta.

Alcuni esemplari raccolti nelle staz. 2, 4 e 5 fra

marzo e luglio.

I CURCULIONIDI IN SENSO LATO (COLEOPTERA ATTELABIDAE. APIONIDAE E CURCULIONIDAE) DEL MONTE BARRO

233

Apion ( Stenopterapion ) tenue Kirby

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie del genere Medicago.

Numerosi esemplari raccolti in marzo e aprile nel¬

le staz. 4, 7 e 8 e in località S.Michele (in un prato at¬

tiguo alla stazione 4).

Apion ( Ischnopterapion ) aeneomicans Wencker

Corotipo: Europeo (EUR).

Presenza in Italia: Liguria, Lombardia, Veneto,

Friuli-Venezia Giulia, Umbria, Marche, Sicilia.

Piante ospiti: specie del genere Dorycninm.

Un unico reperto: staz. 6 (11. VI. 1990, lg. Bonini).

Apion (Ischnopterapion) loti Kirby

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia.

Piante ospiti: specie del genere Lotus.

Numerosi esemplari raccolti un po’ dovunque (la

specie risulta assente solo nelle staz. 8 e 9) da marzo

a luglio.

Apion ( Ischnopterapion ) virens Herbst

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie del genere Trifolium.

Numerosi esemplari raccolti fra marzo e giugno

nelle staz. 1, 3, 4, 7 e 8, in un prato attiguo alla staz. 4,

in un prato attiguo alla staz. 7 e in un prato vicino a

Camporeso.

I Apion (Synapion) ebeninum Kirby

Corotipo: Europeo (EUR).

Presenza in Italia: Liguria, Piemonte, Veneto,

Trentino- Alto Adige, Friuli-Venezia Giulia, Abruzzi.

La specie risulta nuova per la Lombardia.

Piante ospiti: Fabacee dei generi Lotus , Onobry-

chis , Vicia, Astragalus e Trifolium.

Un unico esemplare raccolto nella staz. 7

(23.V.1991, lg. Bonini).

Apion ( Holotrichapion ) pisi Fabricius

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie del genere Medicago.

Numerosi esemplari raccolti da fine marzo a fine

maggio nelle staz. 1, 2, 4, 5, 7 e 9, in un prato attiguo

alla staz. 7, in un prato vicino a Camporeso e in loca¬

lità S.Michele (in un prato attiguo alla stazione 4).

Apion ( Hemitrichapion ) pavidum Germar

Corotipo: Paleartico (PAL).

Presenza in Italia: Italia settentrionale, Toscana,

Lazio, Puglia e Sicilia.

Piante ospiti: Coronilla varia.

Numerosi esemplari raccolti da marzo a giugno

nelle staz. 2 (dove la specie è particolarmente abbon¬

dante a metà giugno), 3, 4, 7 e 8, ai margini di un sen¬

tiero a nord-ovest dei Piani di Barra e, sul versante

meridionale, ai margini di un sentiero che dall’eremo

va alla Sella della Pila.

Apion (Cyanapion) gyllenhali Kirby

Corotipo: Europeo (EUR).

Presenza in Italia: segnalato di gran parte delle re¬

gioni Italiane e di Sicilia, ma non ancora noto di Lom¬

bardia.

Piante ospiti: specie del genere Vicia.

Un unico esemplare raccolto nella staz. 2

(16.V.1991, lg. Bonini).

Apion (Oxystoma) cerdo Gerstàcker

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie del genere Vicia.

Un unico esemplare raccolto nella staz. 6

(23.V.1991, lg. Bonini).

Apion ( Oxystoma ) subulatum Kirby

Corotipo: W-Paleartico (WPA).

Presenza in Italia: noto di gran parte d’Italia e Si¬

cilia.

Piante ospiti: specie del genere Lathyrus.

Un unico esemplare raccolto nella staz. 5

(23.V.1991, lg. Bonini).

Apion ( Oxystoma ) opeticum Bach

Corotipo: Europeo (EUR).

Presenza in Italia: Italia settentrionale e centrale,

Basilicata, Calabria e Sicilia.

Piante ospiti: Lathyrus vernus.

Un unico esemplare raccoilto nella staz. 6

(23.V.1991,lg. Bonini)

Apion (Eutrichapion) gribodoi Desbrochers

Corotipo: S-Europeo (SEU).

Presenza in Italia: Piemonte, Lombardia, Veneto,

Friuli-Venezia Giulia, Emilia-Romagna, Toscana,

Umbria, Lazio, Campania, Basilicata e Calabria.

Piante ospiti: Galega officinalis.

Due esemplari raccolti a nord-ovest dei Piani di

Barra (23.VI.1991, lg. Bonini).

Apion ( Eutrichapion ) ervi Kirby

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie dei generi Lathyrus e Vicia.

Alcuni esemplari raccolti in maggio e giugno nel¬

le staz. 1, 2, 3, 6, 7 e 8, ai margini di un sentiero a nord-

ovest dei Piani di Barra e in un prato presso Campo¬

reso.

Apion ( Eutrichapion ) viciae Paykull

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie dei generi Lathyrus e Vicia.

Alcuni esemplari raccolti in maggio nelle staz. 2, 3,

6 e 7 e in un prato presso Camporeso.

Otiorhynchus (s.str.) salicicola Heyden

Corotipo: Alpino.

Presenza in Italia: Italia settentrionale, Toscana.

Piante ospiti: specie verosimilmente polifaga.

Alcuni esemplari raccolti nelle staz. 3, 4, 7, 8 e nei

boschi della Val Faé in maggio e giugno.

Otiorhynchus (s.str.) vehemens Boheman

Corotipo: Alpino.

Presenza in Italia: Alpi e Prealpi occidentali, Ap¬

pennino settentrionale.

Piante ospiti: specie verosimilmente polifaga.

Alcuni esemplari raccolti in maggio e giugno nel¬

le staz. 2, 3, 6, 7 e 8, nei prati sotto Sella della Pila (m

700) e nei boschi della Val Faè.

234

CARLO PESARINI

Otiorhynchus (s. str.) frescati Boheman

Corotipo (SEU)

Presenza in Italia: Italia settentrionale e centrale,

Campania.

Piante ospiti: specie polifaga.

Un esemplare raccolto nella staz. 9 (15.VI.1990, lg.

Sassi) e uno in un prato della Val Faè vicino alla staz.

7 (25.IV.1990, lg. Sassi).

Otiorhynchus ( Dorymerus ) carmagnolae Villa

Corotipo: Alpino.

Presenza in Italia: Alpi e Prealpi biellesi e lombar¬

de.

Piante ospiti: specie verosimilmente polifaga.

Alcuni esemplari raccolti nelle staz. 2 e 5 e nei bo¬

schi della Val Faè in giugno e luglio.

Otiorhynchus (Toumieria) ovatus (Linneo)

Corotipo: Centroasiatico-Europeo (CAE).

Presenza in Italia: Italia settentrionale, Emilia-Ro¬

magna, Toscana, Abruzzi.

Piante ospiti: specie polifaga.

Un unico reperto (staz. 4, 30.V.1989, lg. Sassi).

Homorhythmus hirticomis (Herbst)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia, Sicilia.

Piante ospiti: specie polifaga.

Numerosi esemplari raccolti in maggio e giugno

nelle staz. 1, 2, 5, 6 e 7, ai margini di un sentiero a

nord-ovest dei Piani di Barra e nei boschi della Val

Faè.

Phyllobius (Parnemoicus) subdentatus Boheman

ssp .roboretanus Gredler

Corotipo: Europeo (EUR).

Presenza in Italia: Italia settentrionale e centrale.

Piante ospiti: Salicacee e Rosacee.

Numerosi esemplari raccolti nelle staz. 2, 3, 5, 6 e

9 e nei prati sotto Sella d. Pila (m 700) in maggio e

giugno.

Phyllobius ( Parnemoicus ) chloropus (Linneo)

Corotipo: Europeo (EUR).

Presenza in Italia: Valle d’Aosta, Piemonte, Lom¬

bardia, Trentino-Alto Adige, Emilia-Romagna, To¬

scana, Marche, Abruzzi, Lazio, Campania, Basilicata.

Piante ospiti: Alnus glutinosa e viridis.

Alcuni esemplari raccolti in maggio nelle staz. 1, 6

e 7 e nei boschi della Val Faè.

Phyllobius (s.str.) virideaeris Laicharting ssp .pada-

nus Pesarini

Corotipo: Alpino.

Presenza in Italia: Italia settentrionale.

Piante ospiti: Salicacee.

Alcuni esemplari raccolti nelle staz. 1, 2, 3 e 5 in

maggio e giugno.

Phyllobius (s.str.) pyri (Linneo) s. str.

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: la sottospecie nominale è diffu¬

sa in tutta l’Italia settentrionale e centrale.

Piante ospiti: Rosacee arboree o arbustive.

Numerosissimi esemplari raccolti un po’ dovun¬

que (la specie non è stata rinvenuta solamente nella

staz. 4) da aprile a giugno.

Phyllobius (s.str.) etruscus Desbrochers

Corotipo: Alpino-Appenninico.

Presenza in Italia: tutta Italia, Sicilia.

Piante ospiti: Rosacee e Salicacee.

Alcuni esemplari raccolti in aprile e maggio nella

staz. 3 e in un prato della Val Faè vicino alla staz. 7.

Phyllobius (Dieletus) argentatus (Linneo) s.str.

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia.

Piante ospiti: Rosacee.

Alcuni esemplari raccolti in maggio e giugno nel¬

le staz. 2, 3, ai margini di un sentiero a nord-ovest dei

Piani di Barra e nei boschi della Val Faè.

Polydrusus (Metallites) marginatus Stephens

Corotipo: W-Europeo (WEU).

Presenza in Italia: tutta Italia

Piante ospiti: Rosacee.

Un esemplare raccolto nei boschi della Val Faè

(30. V. 1990, lg. Bonini).

Polydrusus (Metallites) atomarius (Olivier)

Corotipo: Centroeuropeo (CEU).

Presenza in Italia: regioni alpine e Appennino set¬

tentrionale.

Piante ospiti: Conifere.

Un esemplare raccolto nella staz. 7 (22.VI.1992, lg.

Leonardi).

Polydrusus (Tylodrusus) corruscus Germar, Figg. 1,5

Corotipo: Europeo (EUR).

Presenza in Italia: Piemonte, Lombardia, Veneto,

Trentino- Alto Adige, Toscana.

Fig. 1 - Polydrusus corruscus Germar, cT.

I CURCULIONIDI IN SENSO LATO (COLEOPTERA ATTELABIDAE. APIONIDAE E CURCULIONIDAE) DEL MONTE BARRO

235

Piante ospiti: specie del genere Salix.

Un esemplare raccolto nella staz. 7 (23.V.1991, lg.

Bonini).

Osservazioni: singolarmente, questa specie risulta

esclusa dalla fauna italiana nel citato lavoro di Ab-

bazzi & Osella (1992), a dispetto delle precedenti se¬

gnalazioni di svariati autori. Tale esclusione non è da

attribuirsi ad una semplice svista, poiché essa viene

esplicitamente ribadita nel successivo lavoro di Ab-

bazzi. Osella, Calamandrei & Altea (1993), in cui P.

corruscus è elencato fra le specie che si ritengono er¬

roneamente segnalate d’Italia. Oltre al reperto relati¬

vo al M. Barro, ho personalmente raccolto in serie

questa specie anche nei dintorni di Lodi lungo la

sponde del fiume Adda su Salix (9.V.65). Essa si può

distinguere agevolmente dagli affini P pterygomalis

Boheman e Pflavipes (Degeer) in base ai seguenti ca¬

ratteri, già sottolineati in parte da precedenti autori:

1 Porzione dorsale delle tempie fortemente ed an¬

golosamente rilevata a ciascun lato, occhi relativa¬

mente grandi e poco convessi (Fig. 3). Elitre con

pubescenza biancastra discretamente lunga e den¬

sa, sollevata in modo netto anche nella porzione

basale . pterygomalis Boheman

- Porzione dorsale delle tempie debolmente e non

angolosamente rilevata, occhi più piccoli e con¬

vessi (figg. 4, 5). Pubescenza elitrale, nella porzio¬

ne basale, pressoché totalmente coricata . 2

2 Elitre con pubescenza formata da peli nerastri

nettamente sollevati sulla porzione apicale. Occhi

discretamente ma non fortemente convessi, a con¬

vessità uniforme (Fig. 4) . flavipes (Degeer)

- Elitre con pubescenza formata da peli biancastri

totalmente coricati su tutta la superficie. Occhi

fortemente convessi, a convessità leggermente ir¬

regolare (Fig. 5) . corruscus Germar

Polydrusus (Tylodrusus) pterygomalis Boheman,

Figg- 2, 3

Corotipo: sibirico-europeo (SIE).

Presenza in Italia: tutta Italia

Piante ospiti: diverse specie arboree di Fagales.

Un esemplare raccolto nei boschi della Val Faè

(23.V.1991, lg. Sassi).

Polydrusus (Eustolus) cervinus (Linneo)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutta Italia, Sicilia.

Piante ospiti: specie rizofaga allo stato larvale su

Dactylis glomerata.

Numerosi esemplari raccolti in maggio e giugno nel¬

le staz. 2, 3, 4, 5 e 6 e sul versante meridionale, ai mar¬

gini di un sentiero che dall’eremo va alla Sella della Pi¬

la.

Polydrusus ( Eustolus ) confluens Stephens

Corotipo: Europeo (EUR).

Presenza in Italia: Piemonte, Lombardia, Friuli-

Venezia Giulia, Emilia-Romagna.

Piante ospiti: specie dei generi Cytisus , Ulex e Ge¬

nista.

Alcuni esemplari raccolti nelle staz. 1, 3 e 5 in

maggio.

Figg. 3-5 - Capo visto di tre quarti di: 3) Polydrusus pterygomalis

Boheman; 4) P. flavipes (Degeer) e 5) P corruscus Germar.

Polydrusus (Thomsoneonymus) sericeus (Schaller)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia

Piante ospiti: specie polifaga.

Numerosi esemplari raccolti in tutte le stazioni

(ad eccezione delle staz. 1 e 8) da fine aprile a metà

giugno.

Liophloeus (s.str.) tessulatus (Muller) s.str.

Corotipo: Centroeuropeo (CEU).

Presenza in Italia: Piemonte, Valle d'Aosta, Lom¬

bardia, Veneto, Trentino-Alto Adige.

Piante ospiti: Heracleum sphondylium.

Due esemplari (staz. 5, 30.V.1991, lg. Leonardi, e

staz. 8, 16.V.1990, lg. Sassi).

Stasiodis parvulus (Fabricius)

Corotipo: Alpino- Appenninico.

Presenza in Italia: Liguria, Piemonte, Lombardia,

Trentino-Alto Adige, Emilia-Romagna, Toscana,

Umbria, Abruzzi.

236

CARLO PESARINI

Piante ospiti: Trifolium repens.

Numerosissimi esemplari raccolti in gran parte

delle stazioni (la specie non è stata rinvenuta nelle

staz. 7 e 9) in maggio e giugno.

Sciaphilus asperatus (Bonsdorff)

Corotipo: Centroeuropeo (CÉU).

Presenza in Italia: Piemonte, Lombardia, Veneto,

Trentino-Alto Adige, Toscana.

Piante ospiti: Primula officinali.

Un singolo esemplare raccolto nei boschi della Val

Faé (11. VI. 1991, lg. Bonini).

Strophosoma (s.str.) melanogrammum (Forster)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia, Sardegna.

Piante ospiti: specie polifaga.

Numerosi esemplari raccolti a fine aprile e maggio

nelle staz. 1, 2, 5 e nei boschi della Val Faè.

Barynotus obscurus (Fabricius)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia, Sicilia.

Piante ospiti: specie polifaga.

Alcuni esemplari raccolti a maggio nelle staz. 2 e 6.

Sitona (s.str.) tibialis (Herbst)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutta Italia.

Piante ospiti: specie dei generi Cytisus, Genista e

Ulex.

Alcuni esemplari raccolti da fine marzo a fine

maggio nelle staz. 5 e 6, inoltre ai margini di un sen¬

tiero che va dall’eremo alla Sella d. Pila e in un prato

della Val Faè vicino alla staz. 7.

Sitona (s.str.) suturali Stephens

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia.

Piante ospiti: specie dei generi Vida e Lathyrus.

Un singolo esemplare raccolto nella staz. 5

(30.V.1991, lg. Leonardi).

Sitona (s.str.) sulcifrons (Thunberg) ssp.argutulus

Gyllenhal

Corotipo: S-Europeo (SEU).

Presenza in Italia: tutta Italia.

Piante ospiti: specie dei generi Trifolium e Medi-

cago.

Numerosi esemplari raccolti in tutte le stazioni da

marzo a settembre.

Sitona (s.str.) Jlavescens (Marsham)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia.

Piante ospiti: Papilionacee, soprattutto dei generi

Trifolium e Medicago.

Un esemplare raccolto nella staz. 5 (10. VI. 1991, lg.

Bonini) e uno nella staz. 9 (15. VI. 1990, lg. Sassi).

Sitona (s.str.) puncticollis Stephens

Corotipo: Centroasiatico-Europeo (CAE).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: Papilionacee, soprattutto del genere

Trifolium.

Due esemplari raccolti il 10. VI. 1991 nella staz. 1

(lg. Leonardi) e nella staz. 2 (lg. Bonini).

Sitona (s.str.) humeralis Stephens

Corotipo: W-Paleartico (WPA).

Presenza in Italia: tutta Italia.

Piante ospiti: Papilionacee, soprattutto del genere

Medicago.

Alcuni esemplari raccolti nelle staz. 4, 5, 7, 9 e in

Località San Michele (in un prato attiguo alla stazio¬

ne 4) da fine marzo a giugno.

Sitona (s.str.) hispidulus (Fabricius)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutta Italia.

Piante ospiti: Papilionacee.

Alcuni esemplari raccolti nelle staz.l, 3, 7, 8 e in

località San Michele (in un prato attiguo alla stazio¬

ne 4) da marzo a giugno.

Pseudocleonus cinereus (Schrank)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: diverse Asteracee.

Un esemplare raccolto in un prato della Val Faé

prossimo alla staz. 7 (6.V.1990, lg. Sassi) e un altro nei

prati sotto Sella della Pila (m 700) (30.V.1990, lg. Sassi).

Pseudocleonus grammicus (Panzer)

Corotipo: Europeo (EUR).

Presenza in Italia: Italia settentrionale.

Piante ospiti: Centaurea jacea.

Un esemplare raccolto nella staz. 2 (25. Vili. 1992,

lg. Sassi) ed uno nella staz. 3 (10.X.1991, lg. Leonardi).

Lixus (Dilixellus) bardanae (Fabricius)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia.

Piante ospiti: specie del genere Rumex.

Un unico reperto (staz. 1, 9.VI.1991, lg. Sassi)

Larinus (Larinorhynchus) stumus (Schaller)

Corotipo: W-Paleartico (WPA).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie del genere Cirsium , più di ra¬

do Carduus e Centaurea.

Alcuni esemplari raccolti nelle staz. 2, 3 e 9 da

maggio a ottobre.

Larinus (Larinomesius) obtusus Gyllenhal

Corotipo: Centroasiatico-Europeo (CAE).

Presenza in Italia: tutta Italia, Sicilia.

Piante ospiti: specie del genere Centaurea.

Numerosi esemplari raccolti da maggio a settem¬

bre nelle staz. 1, 2, 3, 5, 6, ai margini di un sentiero a

nord-ovest dei Piani di Barra e ai margini di un sen¬

tiero che dall’eremo porta alla Sella della Pila.

Hypera zoilus (Scopoli)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie dei generi Trifolium e Medicago.

Tre esemplari raccolti nelle staz. 2, 3 e in località

San Michele (in un prato attiguo alla stazione 4) da

giugno a ottobre.

Hypera vidua (Gené), Fig. 6

Corotipo: Alpino.

Presenza in Italia: Liguria, Piemonte, Lombardia,

Trentino-Alto Adige, Toscana.

Piante ospiti: specie del genere Geranium.

I CURCULIONIDI IN SENSO LATO (COLEOPTERA ATTELABIDAE. APIONIDAE E CURCULIONIDAE) DEL MONTE BARRO

237

Fig. 6 - Hypera vidua (Gené), 8, habitus.

Quattro esemplari raccolti nella staz.2 (10.III.1991,

lg. Leonardi, 14.III.1990 e 10.X.1991 lg. Sassi) e un

esemplare nella staz. 5 (18.VI.1991, lg. Sassi).

Hypera nigrirostris (Fabricius)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutta Italia.

Piante ospiti: specie dei generi Trifolium e Ononis.

Un esemplare raccolto nella staz. 7 (23.V.1991, lg.

Bonini).

Hypera postica (Gyllenhal)

Corotipo: Olartico (OLA).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie dei generi Trifolium e Medi-

cago.

Due esemplari raccolti il 25.IV.1990 (lg. Sassi) nel¬

la staz. 7 e in un prato attiguo alla stessa.

Hypera venusta (Fabricius)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: numerose specie di Papilionacee.

Quattro esemplari raccolti nella staz. 5 (16.V.1990

e 8.VII.1990, lg. Leonardi e Sassi).

Donus oxalidis (Herbst)

Corotipo: Europeo (EUR).

Presenza in Italia: Italia settentrionale.

Piante ospiti: Petasites e Adenostyles.

Un esemplare raccolto nella staz. 2 (12. VII. 1992,

lg. Sassi), uno nella staz. 7 (23.V.1991, lg. Bonini), al¬

cuni esemplari nel bosco sottostante al monumento

dell’ Alpino e un altro nei boschi della vai Faè.

Donus intermedius (Boheman)

Corotipo: Centroeuropeo (CEU).

Presenza in Italia: Piemonte, Lombardia, Trenti¬

no-Alto Adige, Friuli-Venezia Giulia, Emilia-Roma¬

gna, Toscana, Marche.

Piante ospiti: specie del genere Mentha.

Due esemplari raccolti nella staz. 1 (18. VI. 1991 e

10.X.1991, lg. Sassi), uno nella staz. 2 (12. VII. 1991, lg.

Sassi) ed uno nella staz. 4 (10.X.1990, lg. Leonardi).

Limobius borealis (Paykull)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie del genere Geranium.

Numerosissimi esemplari raccolti nelle staz. 1,2,4,

5 e 6 da marzo a giugno.

Lepyrus capucinus (Schaller)

Corotipo: Europeo (EUR).

Presenza in Italia: Liguria, Piemonte, Lombardia,

Veneto, Trentino-Alto Adige, Emilia-Romagna, To¬

scana, Lazio.

Piante ospiti: specie polifaga.

Alcuni esmplari raccolti in giugno nella staz. 9.

Hylobius (Hylobitelus) transversovittatus (Goeze)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Piemonte, Lombardia, Trenti¬

no-Alto Adige, Emilia-Romagna, Toscana, Lazio,

Campania, Basilicata, Sicilia.

Piante ospiti: Lythrum salicaria.

Alcuni esemplari raccolti nella staz. 9 nei mesi di

maggio, giugno, settembre e ottobre (lg. Sassi).

Liparus (s.str.) dirus (Herbst)

Corotipo: Centroeuropeo (CEU).

Presenza in Italia: Italia settentrionale e centrale.

Piante ospiti: specie del genere Laserpitium.

Numerosi esemplari raccolti a maggio nelle staz.

2, 5, 6 e 7, inoltre presso la vetta e lungo un sentiero

che dall’eremo va alla Sella della Pila.

Leiosoma concinnum Boheman

Corotipo: Alpino.

Presenza in Italia: Piemonte, Lombardia, Veneto,

Trentino- Alto Adige, Toscana, Marche.

Piante ospiti: biologia sconosciuta.

Due esemplari raccolti nella staz. 8 (25.IV. 1990, lg.

Sassi e 16.V.1990, lg. Bonini).

Magdalis (Neopanus) cerasi (Linneo)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: Rosacee arboree ed arbustive.

Alcuni esemplari raccolti a maggio nelle staz. 8 e 9

e sul versante meridionale, ai margini di un sentiero

che dall'eremo va alla Sella della Pila.

Magdalis ( Neopanus ) exarata Brisout

Corotipo: Europeo (EUR).

Presenza in Italia: nota di gran parte delle regioni

d’Italia e di Sicilia, ma non mancora segnalata per la

Lombardia.

Piante ospiti: specie del genere Quercus.

Alcuni esemplari raccolti a maggio nella staz. 6 e

sotto la vetta del M. Barro

238

CARLO PESARINI

Acalles lemur (Germar)

Corotipo: Europeo (EUR).

Presenza in Italia: Italia settentrionale e centrale,

Calabria.

Piante ospiti: specie polifaga.

Un unico esemplare raccolto nel sottobosco della

Val Faé (21.IX.1992).

Echinodera ( Ruteria ) hypocrita (Boheman)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia, Sicilia.

Piante ospiti: specie polifaga.

Due reperti (staz. 7, 21.V.1991, lg. Bonini; staz. 8,

25. V. 1990, lg. Sassi)).

Mononychus punctumalbum (Herbst)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: Iris pseudacorus.

Svariati esemplari raccolti in maggio e giugno nel¬

le staz. 6 e 9.

Rhinoncus (s.str.) bruchoides (Herbst)

Corotipo: Paleartico (PAL).

Presenza in Italia: noto di gran parte dell’Italia

settentrionale e centrale, Campania, Basilicata e Sar¬

degna.

Piante ospiti: specie del genere Polygonum.

Alcuni esemplari raccolti in maggio e giugno nel¬

le staz. 1, 2 e 4.

Rhinoncus (s.str.) pericarpius (Linneo)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie del genere Rumex.

Alcuni esemplari raccolti a maggio nelle staz. 1, 2,

4, 5 e 9.

Rhinoncus (Amalorhinoncus) perpendicularis (Rei-

che)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie del genere Polygonum.

Un unico reperto (staz. 9, 15.VI.1990, lg. Sassi).

Pelenomus comari (Herbst)

Corotipo: Europeo (EUR).

Presenza in Italia: Liguria, Piemonte, Lombardia,

Veneto, Trentino-Alto Adige, Emilia-Romagna, To¬

scana.

Piante ospiti: svariate piante di diverse famiglie:

Lythrum salicaria, Comarum palustre, Alchemilla vul-

garis, Sanguisorba officinalis, Polygonum persicaria.

Un unico reperto (staz. 9, 30.III.1990, lg. Leonar¬

di).

Tapinotus sellatus (Fabricius)

Corotipo: Europeo (EUR).

Presenza in Italia: Piemonte, Lombardia, Veneto,

Friuli-Venezia Giulia, Emilia-Romagna, Toscana, Lazio.

Piante ospiti: Lysimachia vulgaris.

Un unico reperto (staz. 9, 15. VI. 1990, lg. Sassi).

Ceutorhynchus (s.str.) floralis (Paykull)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: svariate Brassicacee, ma soprattutto

Capsella bursa-pastoris.

Alcuni esemplari raccolti nelle staz. 1-5, da fine

marzo a maggio.

Ceutorhynchus (s.str.) erysimi (Fabricius)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: svariate Brassicacee, ma soprattutto

Capsella bursa-pastoris.

Alcuni esemplari raccolti nelle staz. 1, 2, 3 e 4,

presso l’Osservatorio ornitologico e ai margini di un

sentiero che dall’eremo porta alla Sella della Pila.

Ceutorhynchus (s.str.) contractus (Marsham)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: numerose specie di svariate famiglie,

soprattutto Brassicaee e Resedacee.

Numerosi esemplari raccolti nelle staz. 3, 4, 5, 7 e

8 da fine marzo a giugno.

Ceutorhynchus (s.str.) cochleariae (Gyllenhal)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: noto di gran parte d’Italia set¬

tentrionale e centrale, Basilicata.

Piante ospiti: numerose specie di Brassicacee.

Due reperti in staz. 3 (9.V.1990, lg. Sassi;

16.V.1991,lg. Bonini).

Ceutorhynchus (Glocianus) punctiger (Gyllenhal)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutta Italia.

Piante ospiti: Taraxacum officinale.

Alcuni esemplari raccolti nelle staz. 1, 2, 3 e 8 in

marzo e maggio.

Ceutorhynchus (Glocianus) distinctus Brisout

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia, Sicilia.

Piante ospiti: Asteracee dei generi Hypochoeris,

Crepis, Lactuca e Hieracium.

Alcuni esemplari raccolti a maggio nelle staz. 1, 2,

3 e 5.

Nedyus quadrimaculatus (Linneo)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: Unica dioica.

Alcuni esemplari raccolti in maggio e giugno nel¬

le staz. 2, 3, 5 e 9 e nei boschi della Val Faè.

Thamiocolus signatus (Gyllenhal)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: Liguria, Piemonte, Veneto,

Trentino- Alto Adige, Friuli-Venezia Giulia, Lazio. La

specie risulta nuova per la Lombardia.

Piante ospiti: Stachys recta.

Alcuni esemplari raccolti nella staz. 2 tra il 23.V e

il 10. VI.

Trichosirocalus rufulus (Dufour)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: Lombardia, Emilia-Romagna,

Toscana, Italia meridionale, Sicilia.

Piante ospiti: specie del genere Plantago.

Un unico reperto (staz. 8, 14.III.1990, lg. Leonardi).

Trichosirocalus troglodytes (Fabricius)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

CURCULIONIDI IN SENSO LATO (COLEOPTERA ATTELABIDAE, APIONIDAE E CURCULIONIDAE) DEL MONTE BARRO

239

Piante ospiti: Plantago lanceolata.

Alcuni esemplari raccolti da marzo a maggio nel¬

le staz. 3, 5 e 8.

Micrelus ericae (Gyllenhal)

Corotipo: Europeo (EUR).

Presenza in Italia: Piemonte, Lombardia, Veneto,

Trentino-Alto Adige, Friuli-Venezia Giulia, Emilia-

Romagna, Toscana.

Piante ospiti: Calluna vulgaris.

Numerosi esemplari raccolti nella staz. 5 fra il

16.V e il 10. VI.

Zacladus geranii (Paykull)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie del genere Geranium.

Numerosissimi esemplari raccolti in maggio e giu¬

gno nelle staz. 1, 2, 4, 5, 6, 7, 8 e 9, presso l’Osservato-

rio ornitologico, a Camporeso, ai margini di un sen¬

tiero a nord-ovest dei Piani di Barra e nei boschi del¬

la Val Faè.

Coeliodes dryados (Gmelin)

Corotipo: Europeo (EUR).

Presenza in Italia: Liguria, Piemonte, Trentino-Al¬

to Adige, Emilia-Romagna, Toscana, Umbria, Campa¬

nia, Puglia. La specie risulta nuova per la Lombardia.

Piante ospiti: Quercus robur e petraea.

Un unico reperto (staz. 2, 3.IV.1991, lg. Bonini).

Orobitis cyaneus (Linneo)

Corotipo: Europeo (EUR).

Presenza in Italia: Piemonte, Lombardia, Veneto,

Trentino-Alto Adige, Emilia-Romagna, Toscana, La¬

zio, Abruzzi, Campania, Calabria.

Piante ospiti: specie del genere Viola.

Un unico esemplare raccolto nei boschi della Val

Faè (25.IV.1990, lg. Sassi).

Baris scolopacea Germar

Corotipo: Centroasiatico-Europeo (CAE).

Presenza in Italia: Piemonte, Lombardia, Veneto,

Toscana, Lazio, Campania, Sicilia, Sardegna.

Piante ospiti: Chenopodiacee.

Due soli reperti (staz 4, 8.VII.1990, lg. Sassi e staz.

5, 28.V.1990, lg. Bonini).

Limnobaris t-album (Linneo)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia.

Piante ospiti: Ciperacee.

Alcuni esemplari raccolti nella staz. 9 da marzo a

giugno.

Anthonomus (s.str.) rubi (Herbst)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia.

Piante ospiti: numerose specie di Rosacee.

Numerosi esemplari raccolti da aprile a giugno

nelle staz. 1, 2, 3, 4, 5, 6, 8, 9 e sul versante meridiona-

ì le, ai margini di un sentiero che va dalPeremo alla

I Sella della Pila.

Curculio glandium Marsham

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie del genere Quercus.

Alcuni esemplari raccolti in aprile e maggio nelle

staz. 2 e 5.

Curculio nucum Linneo

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia.

Piante ospiti: Corylus avellana.

Alcuni esemplari raccolti da maggio a luglio nelle

staz. 2 e 5.

Balanobius pyrrhoceras (Marsham)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: parassita di galle di Cinipidi su querce.

Alcuni esemplari raccolti nelle staz. 2, 5 e 6 e in un

prato della Val Faè vicino alla staz. 7.

Tychius (s.str.) meliloti Stephens

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie del genere Melilotus.

Alcuni esemplari raccolti fra il 9.V e 1T1.VI nella

staz. 9.

Tychius (s.str.) polylineatus (Germar)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie del genere Trifolium.

Un unico reperto (staz. 5, 23. V. 1991, lg. Bonini).

Tychius (s.str.) schneideri (Herbst)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia, Sicilia.

Piante ospiti: Anthyllis vulneraria.

Alcuni esemplari raccolti in maggio nelle staz. 5 e 6.

Tychius (s.str.) junceus (Reich)

Corotipo: Centroasiatico-Europeo (CAE).

Presenza in Italia: noto di gran parte dellTtalia

settentrionale e centrale, Basilicata, Sicilia.

Piante ospiti: specie dei generi Trifolium e Melilotus.

Un unico reperto (staz. 6, 23. V. 1991, lg. Bonini).

Tychius (s.str.) stephensi Schònherr

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia, Sicilia.

Piante ospiti: Specie del genere Trifolium, soprat¬

tutto T.pratense.

Numerosi esemplari raccolti nelle staz. 1, 2, 3, 4, 5,

6, 8 e 9 e nei boschi della Val Faè.

Tychius (s.str. ) longicollis Brisout

Corotipo: S-Europeo (SEU).

Presenza in Italia: tutta Italia.

Piante ospiti: Ononis repens.

Alcuni esemplari raccolti a maggio nella staz. 2 e

nei boschi della Val Faè.

Tychius (s.str.) picirostris (Fabricius)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie del genere Trifolium , soprat¬

tutto T. repens.

Alcuni esemplari raccolti in maggio e giugno nel¬

le staz. 3 e 5.

Tychius (s.str.) cuprifer (Panzer)

Corotipo: W-Paleartico (WPA).

240

CARLO PESARINI

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie del genere Trifolium.

Alcuni esemplari raccolti in maggio e giugno nel¬

le staz. 1, 2, 3 e 5 e in un prato presso Camporeso.

Sibinia viscariae (Linneo)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia.

Piante ospiti: specie dei generi Silene e Lychnis.

Alcuni esemplari raccolti in maggio e giugno nel¬

le staz. 1, 2, 3, 4 e 7.

Sibinia pellucens (Scopoli)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutta Italia.

Piante ospiti: Lychnis dioica.

Alcuni esemplari raccolti da maggio a luglio nelle

staz. 2, 3, 4 e 5 e nei boschi della Val Faè.

Dorytomus (s.str.) taeniatus (Fabricius)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutta Italia, Sicilia.

Piante ospiti: Salicacee.

Alcuni esemplari raccolti in maggio e giugno nel¬

la staz. 1.

Dorytomus (Olamus) rufatus (Bedel)

Corotipo: Europeo (EUR).

Presenza in Italia: Piemonte, Lombardia, Trenti¬

no-Alto Adige, Emilia- Romagna, Toscana, Abruzzi,

Molise.

Piante ospiti: specie del genere Salix.

Numerosi (25) esemplari raccolti nella staz. 9

(16.V.1990, lg. Leonardi). Oltre a questa serie, la spe¬

cie è stata raccolta nella medesima stazione solo in

tre esemplari (25.V.1990, lg. Sassi e 19.V.1991, lg. Leo¬

nardi), il che indica come la specie presenti verosi¬

milmente una comparsa massiccia e di breve durata,

discontinua da un anno all’altro.

Notaris (s.str.) scirpi (Fabricius)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Piemonte, Lombardia, Veneto,

Emilia-Romagna, Toscana, Umbria, Abruzzi, Molise,

Basilicata, Calabria, Sicilia.

Piante ospiti: Carex paludosa.

Un unico reperto (staz. 9, 25.V.1990, lg. Sassi).

Pachytychius (s.str.) sparsutus (Olivier)

Corotipo: W-Paleartico (WPA).

Presenza in Italia: tutta Italia, Sicilia.

Piante ospiti: specie dei generi Cytisus, Genista e

Ulex.

Numerosi esemplari raccolti in maggio e giugno

nelle staz. 5 e 6, inoltre lungo un sentiero a nord-ove¬

st dei Piani di Barra e nei prati intorno alla Sella d. Pi¬

la.

Rhynchaenus (s.str.) rufus (Schrank)

Corotipo: Europeo (EUR).

Presenza in Italia: Piemonte, Lombardia, Trenti¬

no-Alto Adige, Friuli-Venezia Giulia, Emilia-Roma¬

gna, Toscana, Lazio, Basilicata, Sardegna.

Piante ospiti: Ulmus campestris.

Un esemplare raccolto presso l’Osservatorio orni¬

tologico (13. VI. 1990, lg. Bonini) e uno nei prati verso

Sella della Pila (6. VII. 1990, lg. Sassi).

Rhynchaenus (Alyctus) signifer (Creutzer)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia.

Piante ospiti: specie del genere Quercus, soprat¬

tutto Q. robur.

Due esemplari raccolti nella staz. 2 (1 5. VI. 1990, lg.

Leonardi), uno nei prati sotto la Sella d. Pila

(30. V.l 990, lg. Sassi), e uno ai margini di un sentiero

che dall’eremo porta alla Sella della Pila (30. V. 1990).

Rhynchaenus (Tachyerges) salicis (Linneo)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutta Italia.

Piante ospiti: specie del genere Salix, soprattutto

Salix cinerea.

Un esemplare raccolto nella staz. 9 (24.VI.1989, lg.

Sassi).

Rhamphus pulicarius (Herbst)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie del genere Salix.

Due esemplari raccolti sul versante meridionale, sot¬

to Sella d. Pila (m 700) (6.V.1990 e 30.V.1990, lg. Sassi).

Mecinus janthinus (Germar)

Corotipo: Europeo (EUR).

Presenza in Italia: Noto di gran parte d’Italia, Sicilia.

Piante ospiti: specie del genere Linaria.

Alcuni esemplari raccolti in maggio e giugno nel¬

le staz. 2, 5 e 9.

Mecinus pyraster (Herbst)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: Plantago lanceolata.

Alcuni esemplari raccolti da marzo a giugno nelle

staz. 3, 4, 5 e 9 e nei boschi della Val Faè.

Mecinus circulatus (Marsham)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie del genere Plantago, soprat¬

tutto P. lanceolata.

Alcuni esemplari raccolti in maggio e giugno nel¬

le staz. 1, 9 e nei boschi della Val Faè.

Miarus (Miaromimus) graminis (Gyllenhal)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: noto di gran parte d’Italia.

Piante ospiti: specie del genere Campanula.

Alcuni esemplari raccolti in maggio nelle staz. 2,5,

6, 8 e 9 e in un prato presso Camporeso.

Miarus (Miaromimus) distinctus (Boheman)

Corotipo: Alpino-Appenninico.

Presenza in Italia: Piemonte, Veneto, Emilia-Ro¬

magna, Toscana, Basilicata. Risulta nuovo per la

Lombardia.

Piante ospiti: specie del genere Campanula.

Alcuni esemplari raccolti in giugno nelle staz. 2 e

6, ai margini di un sentiero a nord-ovest dei Piani di

Barra e presso l’Osservatorio ornitologico.

Miarus (Miaromimus) micros (Germar)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: Piemonte, Veneto, Emilia-Roma¬

gna, Sicilia. La specie risulta nuova per la Lombardia.

I CURCULIONIDI IN SENSO LATO (COLEOPTERA ATTELABIDAE, APIONIDAE E CURCULIONIDAE) DEL MONTE BARRO

241

Piante ospiti: verosimilmente Campanulacee.

Un unico reperto (staz. 6, 23.V.1991, lg. Bonini).

Miarus (s.str.) campanulae (Linneo)

Corotipo: Paleartico (PAL).

Presenza in Italia: Liguria, Piemonte, Lombardia,

Veneto, Trentino- Alto Adige, Toscana, Lazio, Campa¬

nia, Calabria.

Piante ospiti: svariate Campanulacee.

Numerosi esemplari raccolti in aprile e maggio

nelle staz. 2, 5, 6 e 8, presso la vetta e ai margini di un

sentiero che dall’eremo porta alla Sella della Pila.

Gymnetron (s.str.) pascuorum (Gyllenhal)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia.

Piante ospiti: Piantalo lanceolata.

Alcuni esemplari raccolti in maggio e giugno nel¬

le staz. 1, 2, 5, 7, 9, presso la stazione di osservazione

ornitologica e nei boschi della Val Faè.

Gymnetron (Rhinusa) tetrum (Linneo)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie del genere Verbscum , più di

rado Scrophularia.

Alcuni esemplari raccolti in giugno nelle staz. 3 e 9.

Gymnetron ( Rhinusa ) antirrhini (Paykull)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutta Italia, Sicilia.

Piante ospiti: specie del genere Linaria.

Un reperto in staz. 2 e uno in staz, 5 (23. V. 1991, lg.

Bonini).

Gymnetron ( Rhinusa ) linariae (Panzer)

Corotipo: Europeo (EUR).

Presenza in Italia: noto di gran parte d’Italia set¬

tentrionale e centrale, Campania, Sicilia.

Piante ospiti: specie del genere Linaria.

Alcuni esemplari raccolti in maggio e giugno nel¬

le staz. 1, 2 e 5 e ai margini di un sentiero a nord-ove¬

st dei Piani di Barra.

Cionus tuberculosus (Scopoli)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia, Sicilia.

Piante ospiti: specie del genere Scrophularia.

Alcuni esemplari raccolti in maggio e giugno nel¬

le staz. 1, 2 e ai margini di un sentiero a nord-ovest dei

Piani di Barra.

Cionus olivieri Rosenschòld

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie del genere Verbascum, so¬

prattutto V. thapsus.

Alcuni esemplari raccolti in maggio e giugno nel¬

le staz. 4 e 5.

Cionus thapsus (Fabricius)

Corotipo: Centroasiatico-Europeo (CAE).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Piante ospiti: specie del genere Verbascum.

Tre esemplari raccolti nella staz. 3 (18.V.1991, lg.

Sassi).

Stereonychus fraxini (Degeer) s.str.

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: noto di gran parte d'Italia, Sicilia.

Piante ospiti: Fraxinus excelsior.

Alcuni esemplari raccolti a maggio nelle staz. 6, 7

e nei boschi della Val Faè.

Nella seguente tabella (Tabella 1) sono riuniti i

dati relativi alla presenza delle specie nelle diverse

stazioni. Nel numero 10 sono riunite le località del

Monte Barro collocate al difuori delle stazioni di rac¬

colta identificate con precisione; si tratta per lo più di

località site nei boschi della Val Faè; indicazioni più

dettagliate, peraltro, si possono ricavare dalla prece¬

dente trattazione delle singole specie.

Tabella 1 - Tabella riassuntiva delle specie raccolte.

242

CARLO PESARINI

I CURCULIONIDI IN SENSO LATO (COLEOPTERA ATTELABIDAE. APIONIDAE E CURCULIONIDAE) DEL MONTE BARRO

243

Considerazioni conclusive

Col presente lavoro vengono segnalate 166 specie

di Curculionidae (sensu lato) per la zona del M. Bar¬

ro. Come già accennato in apertura, si tratta di un

quadro sufficientemente ampio della fauna dell’area

in questione, anche se mancano alcuni elementi, sicu¬

ramente presenti, il cui campionamento avrebbe ri¬

chiesto tecniche di raccolta mirate, come ad esempio

le specie della tribù Cossonini, gli Acalles e più gene¬

ralmente le specie strettamente legate al terreno. Gli

elementi raccolti, peraltro, consentono di delineare

un quadro sicuramente significativo della fauna cur-

culioniodica, dal quale emerge una prevalenza di spe¬

cie mesoterme ad ampia distribuzione, come si può

rilevare dalla tabella 2, basata sulle categorie corolo¬

giche delle specie censite e dalla fig. 7, dove i corotipi

sono raggruppati per categorie sintetiche.

Tabella 2 - Spettro corologico delle specie raccolte.

Le sigle dei corotipi fondamentali sono ricavate dal

lavoro di Vigna Taglianti et al. (1991).

Per quanto riguarda il confronto fra le stazioni 1-

9 in base alle specie che vi sono presenti, utilizzando

l’indice di Dice/Sorensen e applicando la cluster

analysis secondo il metodo WPGMA si è ottenuto il

dendrogramma di somiglianza riportato in fig. 8. Pre¬

scindendo dalla contrapposizione fra la stazione 9 e

le rimanenti, abbastanza ovvia in considerazione del¬

le caratteristiche particolari di quel biotopo, si sepa¬

rano in primo luogo i due prati della Val Faè, proba¬

bilmente per via della loro esposizione fresca, e suc¬

cessivamente la stazione 6, che, oltre ad essere la più

xerotermica,si distingue fisionomicamente dalle altre

stazioni prative per la tendenza molto più spiccata al¬

la ricostruzione della foresta.

Medit.

1,81%

Fig. 7 - Corotipi raggruppati per categorie sintetiche.

Q

0.31 0.48 0.65 0.83 1.00

Fig. 8 - Dendrogramma di similarità fra le stazioni 1-9 basato sui

campionamenti di Curculionidi (indice di Dice/Sorensen + WPG¬

MA).

244

CARLO PESARINI

BIBLIOGRAFIA

Abbazzi P., Colonnelli E., Masutti L. & Osella G., 1995 -

Checklist delle specie della fauna italiana. 61. Coleoptera

Polyphaga XVI (Curculionoidea). Ed. Calderini, Bologna.

Abbazzi P. & Osella G., 1992 - Elenco sistematico-faunistico de¬

gli Anthribidae, Rhinomaceridae, Attelabidae, Apionidae,

Brentidae, Curculionidae italiani. I Parte. Redia , 75:267-427.

Abbazzi R, Osella G., Calamandrei S., Altea T., 1993 - Elen¬

co sistematico-faunistico degli Anthribidae. Rhinomaceridae,

Attelabidae, Apionidae, Brentidae, Curculionidae italiani. II

Parte. Redia, 75:179-221.

Caldara R., 1990 - Revisione tassonomica delle specie palearti¬

che del genere Tychius Germar (Coleoptera Curculionidae).

Metri. Soc. dal. Sci. Nat. Mus. civ. Stor. nat. Milano , Milano,

25:53-218.

Dieckmann L., 1972 - Beitrage zur Insektenfauna der DDR: Co¬

leoptera: Curculionidae, Cethorhynchinae. Beitr. Ent., 22:3-

128.

Dieckmann L., 1977 - Beitrage zur Insektenfauna der DDR: Co¬

leoptera Curculionidae (Apioninae). Beitr. Ent., 27:7 -143.

Pesarini G, 1980 - Le specie paleartiche della tribù Phyllobiini

(Coleoptera Curculionidae). Boll. Zool. agr. Bachic., 15:49-

230.

Porta A., 1932 - Fauna Coleopterorum Italica. Voi. V Rhyn-

chophora Lamellicornia. Piacenza.

Vigna Taglianti A., Audisio P.A., Belfiore G, Biondi M„ Bo¬

logna M.A., Carpaneto G.M., De Biase A., De Felici S.,

Piattella E., Racheli T., Zapparoli M. & Zoia S., 1992 -

Riflessioni di gruppo sui corotipi fondamentali della fauna W-

paleartica ed in particolare italiana. Biogeographia, 16: 159-

179.

Carlo Pesarini: Museo Civico di Storia Naturale di Milano, Corso Venezia 55, 20121 Milano

Studi geobotanici ed entomofaunistici nel Parco Regionale del Monte Barro

Memorie della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano

Volume XXVII - Fascicolo II - 1997

Fausto Pesarini

Gli Imenotteri Sinfiti (Hymenoptera Megalodontidae,

Cephidae, Argidae, Cimbicidae, Tenthredinidae)

del Monte Barro (Italia, Lombardia, Lecco)

Riassunto - L’autore presenta un elenco di 43 specie di Imenotteri Sinfiti censite nell’area del Monte Barro (Lecco). Il

materiale è stato raccolto nell’ambito di una ricerca entomofaunistica condotta dal Museo di Storia Naturale di Milano ne¬

gli anni 1989-1992. La maggior parte delle raccolte è stata effettuata in nove stazioni prative (staz. 1-9), 8 delle quali situa¬

te all’interno del parco regionale. Di ciascuna stazione è fornita una breve descrizione. Per ognuna delle specie censite si

forniscono i dati corologici e biologici essenziali e il numero di esemplari raccolti in ogni stazione con l’indicazione del ses¬

so. Due specie ( Tenthredo diana e Macrophya rufipes ) sono risultate nuove per la Lombardia.

Abstract - Sawflies (Hymenoptera Megalodontidae, Cephidae, Argidae, Cimbicidae, Tenthredinidae) from Monte Bar¬

ro (Italy, Lombardy, Lecco).

The author makes a list of 43 species of Hymenoptera Symphyta collected in thè area of Monte Barro (Lecco). The ma¬

terial has been sampled during a research accomplished by thè Naturai History Museum of Milano in thè years 1989-1992.

Nine sampling sites (eight of which placed inside thè Regional Park) have been especially investigated and briefly descri-

bed. For each sampled species biological and distributional data are given, together with thè number of both male (m) and

female (f) collected specimens.Two species ( Tenthredo diana and Macrophya rufipes ) are new for Lombardy.

Key words: Monte Barro, Symphyta, geographical distribution.

Nel corso delle campagne di raccolta sulla ento-

mofauna del Monte Barro, condotte dal Museo Civi¬

co di Storia Naturale di Milano negli anni 1989-1992,

sono stati campionati 136 esemplari di Imenotteri

Sinfiti appartenenti a 43 specie. Si tratta di un picco¬

lo contingente, che potrebbe certamente venire mol¬

to incrementato con ulteriori indagini. Pur con evi¬

denti lacune (quali ad esempio Punica specie, per di

più alquanto banale, di Nematinae), si può però con¬

siderare tale campione discretamente indicativo del¬

la fisionomia dell’ambiente indagato e della sinfito-

fauna relativa. È degna di nota, infatti, la notevole ali¬

quota di specie infeudate a poacee (almeno 13 su 43,

pari al 30,2 %), molte volte superiore all’analoga

quota (4,2 %) che si ottiene prendendo in esame l’in¬

tero complesso di specie europee di Sinfiti di cui è

nota le pianta ospite (Liston, 1995). Pur non potendo

escludere che abbiano avuto un’influenza non trascu¬

rabile, nella composizione del campione, le tecniche

di raccolta impiegate, nonché la stessa casualità (visto

il numero complessivamente modesto di specie censi¬

te), sembra però plausibile ricollegare tale dato ad

; elementi fisionomici propri delle biocenosi oggetto di

studio.

Nel complesso delle specie censite, due sono ri-

; sultate nuove per la Lombardia ( Tenthredo diana

Benson e Macrophya rufipes (L.)), mentre altre tre

( Sterictiphora angelicae (Panzer), Tenthredopsis d ti¬

bia Konow e Tenthredopsis palmata (Geoffroy)) era¬

no state segnalate, per la stessa regione, sotto altro

; nome.

Osservazioni sulle stazioni di raccolta

La maggior parte delle raccolte va riferita a 9 sta¬

zioni prative (staz. 1-9) di cui si riportano le caratteri¬

stiche ambientali ricavate dal contributo di Banfi,

Galasso & Sassi, in questo stesso volume. Altre sta¬

zioni sono state riunite, nella tabella riassuntiva (tab.

1), sotto il numero 10.

Stazione 1: Località Piani di Barra, 610 m, esp. W,

interessata da scavi archeologici (Grande Edificio). È

caratterizzata da una consistente presenza di prato

falciabile che indica una attività di foraggio residua.

Stazione 2: Località Piani di Barra, 600 m, esp. W,

interessata da scavi archeologici (Edificio II). Si trat¬

ta di una prateria in cui è stata abbandonata la ge¬

stione a foraggio, vi è quindi presente un leggero

mantello.

Stazione 3: Conca prativa a monte del Monumen¬

to dell’Alpino, 630 m, esp. W. Vi si nota la convivenza

di elementi di prateria, elementi di prato falciabile ed

elementi di disturbo marginale.

Stazione 4: Località S. Michele, pendio in prossi¬

mità del sentiero per Pian Sciresa, 325 m, esp. E. Su

una base di Mesobromion è in pieno sviluppo il pra¬

to falciabile, che qui presenta il carattere oligo-meso-

trofico.

Stazione 5: Località Pian Sciresa, 435 m, esp. NE.

È un prato arido con montarozzi residui a brughiera;

per il resto il livello di base è costituito da prateria a

Brachypodium rupestre ssp. caespitosum.

Stazione 6: Superfici prative lungo il sentiero del¬

la «Cresta occidentale», che dall’edificio dell’ex sana-

246

FAUSTO PESARINI

torio sale alla vetta, 750 m, esp. S. Si tratta di una pra¬

teria con parziale affioramento roccioso, fortemente

cespugliata e in via di chiusura, con forte influsso del¬

l’elemento prenemorale (tendenza a un Quercetum

pubescenti s. 1.)

Stazione 7: Località Fornaci Villa, in prossimità

deU’impluvio della Val Faè, 275 m, esp. NW. È una su¬

perficie prativa terrazzata all’interno del bosco meso¬

frio, molto simile a quella della stazione 8 ma più aper¬

ta e con qualche elemento in più di Mesobromion.

Stazione 8: Località Fornaci Villa, in prossimità

dell’impluvio della Val Faè, 305 m, esp. NW. È un pra¬

to terrazzato irregolarmente gestito e contornato da

un bosco con notevoli contrassegni mesofili.

Stazione 9: Località Ca’ di Sala, 226 m, sulla riva

settentrionale del bacino di Oggiono del Lago di An¬

none. Vi si evidenziano tre aspetti essenziali: 1) il can¬

neto, con accenni di aggruppamento a Iris pseudoa-

corus , elementi di magnocariceto e residui di bosca¬

glia ripariale 2) prato umido oligotrofico ( Molinion

coeruleae ); 3) vegetazione erbacea perenne e disor¬

ganizzata al margine superiore della stazione.

Elenco delle specie raccolte

Nell’elenco che segue si è adottato l’ordinamento

seguito nella recentissima check-list dei Sinfiti italia¬

ni di Masutti & Pesarini (1995).

Megalodontidae

Megalodontes cephalotes (Fabricius, 1781)

Corotipo: Centroeuropeo (CEU).

Presenza in Italia: regioni settentrionali, Toscana.

Piante osoiti: Apiacee del genere Peucedanum.

Staz.4: 10.VI.91, leg. Leonardi, 1 f; 18.VI.91, leg.

Sassi, 1 f. Staz. 5: 10.VI.90, leg. Sassi, 1 f. Staz. 7:

19.V.92, leg. Sassi, 1 f.

Megalodontes klugii (Leach, 1817)

= M. spissicornis (Klug, 1824)

Corotipo: Centroeuropeo (CEU).

Presenza in Italia: regioni settentrionali, Toscana.

Piante ospiti: Apiacee dei generi Laserpitium,

Peucedanum, Seseli.

1 f, 30.V.90, leg. Sassi, sul versante meridionale, ai

margini di un sentiero che va dall’eremo alla Sella

della Pila.

Cephidae

Cephus brachycercus Thomson, 1871

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: regioni settentrionali, Toscana,

Marche, Lazio, Sardegna.

Piante ospiti: sconosciute, con molta probabilità

poacee.

Staz. 1: 23.V.91, leg. Sassi, 1 f. Staz. 2: 23.V.91, leg.

Leonardi, 1 f. Staz. 4, 23.V.91, leg. Leonardi, 3 ff.

Cephus cultratus Eversmann, 1847

= C. pilosulus Thomson, 1871

Corotipo: Europeo (EUR).

Presenza in Italia: regioni settentrionali, Toscana e

Sicilia.

Piante ospiti: Poacee dei generi Phleum e Dactylis.

Staz. 1: 23.V.91, leg. Sassi, 1 m; 30.V.91, leg. Sassi, 1

m. Staz. 2: 10. VI. 91. leg. Leonardi, 1 f. Staz. 3: 30.V.91,

leg. Leonardi, 1 f.

Calameuta pallipes (Klug, 1803)

Corotipo: Europeo (EUR).

Presenza in Italia: Piemonte, Valle d’Aosta, Lom¬

bardia, Liguria, Calabria, Sardegna.

Piante ospiti: sconosciute, con molta probabilità

poacee.

Staz. 1: 30.V.91, leg. Leonardi, 1 f. Staz. 2: 15. VI. 89,

leg. Leonardi, 1 f; 10. VI. 91, leg. Leonardi, 1 m. Staz. 8:

19.V.92, leg. Sassi, 1 f.

Argidae

Sterictiphora angeliche (Panzer, 1799)

= S. furcata auctt., partim, nec Villers, 1789

Corotipo: Europeo (EUR).

Presenza in Italia: a lungo confusa con S. furcata

(Villers), l’unico dato Pubblicato era relativo all’Ap-

pennino Romagnolo (Pesarini & Campadelli, in

stampa). Ne ho potuti esaminare, in realtà, esemplari

provenienti da svariate regioni, ed è probabile che

molti dei reperti di S. furcata della letteratura siano

da assegnare a S. angelicae. Di Lombardia essa mi è

nota anche di Casiino al Piano (Pesarini, 1983, sub S.

furcata ) e di Mercallo (in coll. Museo di Milano).

Piante ospiti: sconosciute, probabilmente rosacee.

Staz. 1: 19.V.91, leg. Leonardi, 1 m.

Cimbicidae

Corynis obscura (Fabricius, 1775)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutta Italia e Sicilia.

Piante ospiti: probabilmente Geranium sylvati-

cum.

Staz. 6: 27. VI. 89, leg. Leonardi, 1 f 1 m.

Tentredinidae

Selandriinae

Brachytops flavens (Klug, 1814)

Corotipo: Olartico (OLA).

Presenza in Italia: nonostante l’enorme areale, per

il nostro Paese risulta segnalato solo di Piemonte,

Lombardia e Veneto.

Piante ospiti: Ciperacee del genere Carex.

Staz. 2: 9.IV.90, leg. Leonardi, 1 f 3 mm. Staz. 9:

15.VI.90, leg. Leonardi, 1 m.

Dolerus (Dicrodolerus) vestigialis (Klug, 1814)

Corotipo: Olartico (OLA).

Presenza in Italia: regioni settentrionali e peninsu¬

lari.

Piante ospiti: Equisetum palustre e sylvaticum.

Staz. 9: 19.V.91, leg. Leonardi, 1 f.

Dolerus (Poodolerus) gonager (Fabricius, 1781)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: regioni settentrionali, Toscana,

Lazio, Calabria.

Piante ospiti: Poacee dei generi Agrostis , Festuca ,

Po a.

Staz. 3: 19.V.91, leg. Leonardi, 1 f. Staz. 4: 30.III.90,

leg. Leonardi, 1 f; 23.V.91, leg. Leonardi, 1 f.

Dolerus (Poodolerus) niger (Linnaeus, 1767)

Corotipo: Europeo (EUR).

Presenza in Italia: regioni settentrionali, Toscana,

Lazio, Campania e Calabria.

GLI IMENOTTERI SINFITI (HYMENOPTERA MEGALODONTIDAE, CEìPHIDAE. ARGIDAE. CIMBICIDAE. TENTHREDINIDAE)

247

Piante ospiti: poacee dei generi Avena, Hordeum.

Triticum.

Staz. 1: 23.V.91, leg. Sassi, 1 f.

Dolerus (Poodolerus) picipes (Klug. 1814)

Corotipo: Europeo (EUR).

Presenza in Italia: regioni settentrionali, Marche,

Calabria.

Piante ospiti: Poacee dei generi Agrostis e Festuca.

Staz. 4: 23.V.91, leg. Leonardi, 1 f; 30.V.91, leg. Leo¬

nardi, 1 f. Staz. 5: 30.V.91, leg. Leonardi, 1 f.

Dolerus (Poodolerus) puncticollis Thomson, 1871

Corotipo: Europeo (EUR).

Presenza in Italia: regioni settentrionali, Toscana,

Calabria; mi è noto anche di Lazio, Abruzzo e Puglia

(Gargano).

Piante ospiti: sconosciute, con tutta probabilità

poacee.

Staz. 8: 14.III.90, leg. Sassi, 1 f.

Tenthredininae

Aglaostigma aucupariae Klug, 1814)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: regioni settentrionali, Toscana,

Lazio, Basilicata.

Piante ospiti: Galium mollugo e boreale.

Staz. 2: 19.V.91, leg. Leonardi, 1 m. Staz. 7:

21.IV.92, leg. Sassi, 1 f.

Aglaostigma fulvipes (Scopoli, 1763)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Lombardia, Trentino, Friuli,

Emilia-Romagna e Toscana; mi è noto anche di Pie¬

monte, Veneto, Liguria, Marche, Abruzzo e Calabria.

Piante ospiti: Galium.

Staz. 4: 30.III.90, leg. Sassi, 1 f.

Tenthredopsis dubia Konow, 1890

= T. picticeps auctt. nec Cameron, 1881

Corotipo: Europeo (EUR).

Presenza in Italia: da precisare, data l’estrema in¬

certezza sull’identità delle specie del genere Tenthre¬

dopsis Costa. Con i nomi di T. dubia Konow o pictice¬

ps Cameron risulta segnalata di Veneto, Emilia-Ro¬

magna e Abruzzo, ma è certamente molto più diffusa.

Di Lombardia mi era nota di Faloppio, Olgelasca, Ca-

priano, Calolziocorte (Pesarini, 1983, sub T. nassata

(L.), partim).

Piante ospiti: Triticum vulgare e Agropyron re-

pens.

Staz. 1: 19.V.91, leg. Leonardi, 1 f. Staz. 2: 23.V.91,

leg. Leonardi, 1 m. Staz. 6: 19.V.92, leg. Sassi, 1 f. Staz.

7: 21.IV.92, leg. Leonardi, 1 m.

Tenthredopsis nassata (Linnaeus, 1767)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: tutta Italia continentale, forse

Sicilia.

Piante ospiti: Poacee dei generi Agropyron e De-

schampsia ; anche Carex.

Staz. 6: 19.V.92, leg. Sassi, 2 mm. Staz. 7: 19.V.92.

leg. Sassi, 1 f.

Tenthredopsis palmata (Geoffroy, 1785)

= T. campestri auctt., Partim, nec Linnaeus, 1758

= T. scutellaris (Fabricius, 1798)

Corotipo: Centroeuropeo (CEU).

Presenza in Italia: da precisare, per le stesse ragio¬

ni esposte al riguardo di T. dubia Konow; sembra co¬

munque essere meno diffusa e frequente di quest'ul-

tima. Di Lombardia mi era nota di Olgiate Comasco,

Casiino al Piano, Verano Brianza, Sartirana, Brivio

(Pesarini, 1983, sub T. nassata (L.), partim).

Piante ospiti: Poacee dei generi Agropyron, Dacty-

lis, Festuca e Poa.

Staz. 2: 23.V.91, leg. Sassi, 1 f. Staz. 6, 19.V.92, leg.

Sassi. 1 m; Boschi della Val Faè, 19.V.92, leg. Sassi, 1 f.

Tenthredopsis sordida (Klug, 1814)

Corotipo: Centroeuropeo (CEU).

Presenza in Italia: regioni settentrionali, Toscana,

Abruzzo, Campania, Basilicata, Calabria.

Piante ospiti: Poacee dei generi Agropyron. Arrhe-

naterum, Lolium\ anche Carex.

Staz. 1: 19.V.91, leg. Leonardi, 1 f. Staz. 2: 9.V.90,

leg. Sassi, 1 f 2 mm; 23.V.91, leg. Leonardi, 1 f; 30.V.91,

leg. Leonardi, 1 f. Staz. 8, 16.V.90, 1 f. Inoltre 2 mm

(25.IV.90, leg. Sassi) in un prato della vai Faè prossi¬

mo alla staz. 7.

Tenthredopsis stigma (Fabricius, 1798)

Corotipo: Europeo (EUR).

Presenza in Italia: regioni settentrionali, Toscana,

Abruzzo, Campania, Calabria.

Piante ospiti: Triticum intermedium.

Staz. 6: 19.V.92, leg. Sassi, 2 ff 2 mm. Staz. 8:

19.V.92, leg. Sassi, 1 f.

Rhogogaster genistae Benson, 1949

Corotioo: Europeo-Mediterraneo (EUM).

Presenza in Italia: Piemonte, Lombardia, Friuli-

Venezia Giulia, Liguria, Emilia-Romagna, Toscana.

Piante ospiti: Sarothamnus e Genista.

Staz. 5: 30.V.91, leg. Sassi, 1 m.

Rhogogaster viridis (Linnaeus, 1758)

Corotipo: Olartico (OLA).

Presenza in Italia: in Passato venivano confuse

con Rh. viridis (L.) almeno altre due specie del gene¬

re Rhogogaster Konow. I dati certi riguardano le re¬

gioni settentrionali, la Toscana e il Lazio.

Piante ospiti: specie spiccatamente polifaga, si svi¬

luppa su Salix. Populus, Quercus. e più tipicamente

Alnus ; ma anche su Stellaria, Filipendula, Circaea,

Epilobium ( Chamnaerion ).

Staz. 5: 16.V.90, leg. Sassi, 1 f. Staz. 6: 19.V.92, leg.

Sassi, 1 f.

Tenthredo brevicomis Konow, 1886)

= T. nitidior Konow, 1888 = acerrima Benson, 1952

Corotipo: Europeo (EUR).

Presenza in Italia: per lungo tempo confusa con al¬

meno tre altre specie del gruppo arcuata ; i dati certi

riguardano le regioni settentrionali (Alpi e pedemon¬

te alpino) e l’Appennino daH’Emilia al Molise.

Piante ospiti: Lotus corniculatus.

Staz. 1: 18.VI.91, leg. Sassi, 1 m; 10.X.91, leg. Sassi,

3 ff. Staz. 2: 9.V.90. leg. Sassi, 1 f.

Tenthredo notha Klug, 1814

= T. perkinsi Morice, 1919

Corotipo: Europeo (EUR).

Presenza in Italia: valgono le considerazioni fatte

per la precedente specie. I dati certi riguardano l’in-

248

FAUSTO PESAR1NI

tero arco alpino. l'Abruzzo (Gran Sasso) e il Molise

(Matese).

Piante ospiti: Trifolium repens , Vida cracca.

Boschi della Val Faè, 13. IX. 90, leg Leonardi, 1 f.

Tenthredo sp. gruppo arcuata

Staz. 4: 10. VI. 91, leg. Leonardi. 1 m.

Tenthredo diana Benson, 1968

Corotipo: Europeo (EUR).

Presenza in Italia: descritta come sottospecie ap¬

penninica di T. maculata Geoffroy, T. diana è stata ri¬

conosciuta come specie distinta solo di recente (Pe¬

sarmi, 1989) ed è in realtà assai più ampiamente dif¬

fusa di quanto non si ritenesse un tempo; è attual¬

mente nota di Italia e di Francia, il suo areale di di¬

stribuzione resta però da precisare, perchè è probabi¬

le sia stata per molto tempo confusa con la specie af¬

fine. In Italia i dati certi riguardano Piemonte, Emi¬

lia-Romagna, Toscana, Marche, Abruzzo; nuova per

la Lombardia.

Piante ospiti: sconosciute; l'affine T maculata si

sviluppa su Poacee dei generi Brachypodium e Dacty-

lis.

Staz. 6: 19. V, 92, leg. Sassi, 2 ff.

Pachyprotasis rapae (Linnaeus, 1767)

Corotipo: Olartico (OLA).

Presenza in Italia: regioni settentrionali e peninsu¬

lari.

Piante ospiti: specie polifaga; si sviluppa principal¬

mente su varie Lamiacee, Scrofulariacee, Solanacee e

Asteracee, ma anche su Plantago , Hypericum, Epilo-

bium, Angelica, Sarothamnus, Fraxinus, Quercus,

Corylus.

Boschi della Val Faè, 13.IX.90, leg. Sassi, 1 f. Prato

adiacente alla staz. 4, 13.IX.90, leg. Sassi, 1 f.

Macrophya albipuncta (Fallén, 1808)

Corotipo: Europeo (EUR).

Presenza in Italia: Lombardia, Emilia-Romagna,

Toscana; probabilmente è molto più diffusa, ma non

è frequente.

Piante ospiti: Geranium sylvaticum.

Staz. 1: 30.V.91, leg. Sassi, 1 m. Staz. 2, 23.V.91, leg.

Leonardi, 1 f; idem, leg. Sassi, 1 f 1 m; 9.VI.91, leg. Sas¬

si. 1 f. Staz. 6, 19.V.92. leg. Sassi. 1 m.

Macrophya annulata (Geoffroy, 1785)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutte le regioni settentrionali e

peninsulari, Sicilia.

Piante ospiti: in letteratura è riportata più fre¬

quentemente Potentilla reptans , ma sono indicati an¬

che Rosa, Rubus e Origanum.

Staz. 2: 15. VI. 89, leg. Leonardi, 3 ff; 9.VI.91, leg.

Sassi, 1 m; 10. VI. 91, leg. Leonardi, 2 ff 1 m; 18. VI. 91,

leg. Sassi, 2 ff 1 m. Staz. 4: 10. VI. 91, leg. Leonardi, 1 f.

Staz. 5: 30.V.91, leg. Sassi. 1 f; 18. VI. 91, leg. Sassi, 1 f.

Tornante lungo la strada che sale al monumento del¬

l’Alpino, 9. VI. 91, leg. Sassi, 1 f.

Macrophya duodecimpunctata (Linnaeus, 1758)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: regioni settentrionali, Toscana,

Lazio, Abruzzo, Campania, Basilicata, Calabria.

Piante ospiti: Poacee a foglia coriacea e Ciperacee

( Carex ).

Staz. 2: 18. VI. 91, leg. Sassi, 1 m. Staz. 9: 16.V.90, leg.

Leonardi. 2 mm; idem, leg. Sassi, 2 ff 2 mm; 15. VI. 91,

leg. Leonardi, 1 f.

Macrophya rufipes (Linnaeus, 1758)

Corotipo: Turanico-Europeo (TUE).

Presenza in Italia: Piemonte, Emilia-Romagna,

Toscana, Abruzzo. Sicilia. Probabilmente presente in

tutta Italia come già riportava genericamente Costa

(1894); in letteratura non esistevano comunque dati

lombardi. Di questa regione mi è nota anche del La¬

go d’Endine (in Coll. Pesarini).

Piante ospiti: non note con certezza; forse Vitis vi¬

nifera.

Staz. 9: 15.VI.90, leg. Leonardi, 1 f.

Allantinae

Empria tridens (Konow, 1896)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: da precisare; i dati di letteratu¬

ra riguardano Piemonte e Lombardia.

Piante ospiti: Rosacee dei generi Rubus e Geum.

Boschi della Val Faè, 25.VI.90, leg. Sassi, 1 f.

Ametastegia tenera (Fallén, 1808)

Corotipo: Olartico (OLA).

Presenza in Italia: Piemonte, Lombardia, Trenti¬

no-Alto Adige, Friuli-Venezia Giulia, Liguria; generi¬

camente indicata di Sicilia.

Piante ospiti: piante erbacee varie: Cyrsium lan-

ceolatum , Filipendula ulmaria , più tipicamente Ru-

mex spp..

Staz. 3: 14.III.90, leg. Leonardi, 1 f. Staz. 4: 26.IX.92,

leg. Leonardi, 1 f. Boschi della Val Faè, 25. VI. 90, leg.

Sassi, 1 m.

Emphytus calceatus (Klug, 1814)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: regioni settentrionali, Toscana,

Lazio, Abruzzo; citato di Sardegna, ma il dato proba¬

bilmente è da riferire a E. laticinctus (Lepeletier,

1823) (= E. balteatus (Klug, 1818 nec Klug, 1817)).

Piante ospiti: Rosacee di svariati generi: Filipen¬

dula, Fragaria, Rosa, Rubus, Alchemilla, Sanguisorba.

Staz. 9: 15. VI. 90, leg. Leonardi, 1 f; 16.V.91, leg. Sas¬

si, 1 f; 19.V.91, leg. Leonardi, 1 f.

Emphytus cingulatus (Scopoli, 1763)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Piemonte, Lombardia, Marche,

Abruzzo, Campania. Calabria, Sicilia, Sardegna.

Piante ospiti: Fragaria e Rosa, ma anche Corylus e

Betula.

Staz. 2: 15.VI.89. leg. Leonardi, 1 f.

Athaliinae

Athalia circularis (Klug, 1813)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: regioni settentrionali e peninsu¬

lari, Sardegna.

Piante ospiti: varie Lamiacee e Scrofulariacee, ma

anche Plantago e Capsella.

Staz. 9: 25.V.90, leg. Sassi, 1 m.

Athalia cordata Lepeletier, 1823

Corotipo: W-Paleartico (WPA).

GLI IMENOTTERI SINFITI (HYMENOPTERA MEGALODONTIDAE, CEìPHIDAE, ARGIDAE. CIMBICIDAE, TENTHREDINIDAE)

249

Presenza in Italia: regioni settentrionali e peninsu¬

lari, Sardegna.

Piante ospiti: piante erbacee varie: Ajuga, An-

tirrhinum e Plantago.

Staz. 3: 13. IX. 90, leg. Leonardi, 1 f. Staz. 4,

26. IX. 92, leg. Leonardi, 1 f. Staz. 7: 21.IV.92. leg. Sassi,

1 f. Prato adiacente alla staz. 4, 13. IX. 90, leg. Sassi, 1 f.

Athalia glabricollis Thomson, 1870

Corotipo: W-paleartico (WPA).

Presenza in Italia: tutta Italia, incluse Sicilia e Sar¬

degna.

Piante ospiti: Brassicacee dei generi Diplotaxis,

Erysimum, Raphanus, Sinapis e Sisymbrium.

Staz. 4: 20. IX. 89, leg. Leonardi. 1 f.

Blennocampinae

Monophadnus pallescens (Gmelin. 1790)

Corotipo: Olartico (OLA).

Presenza in Italia: regioni settentrionali, Toscana,

Basilicata, Calabria.

Piante ospiti: diverse specie del genere Ranuncu-

lus.

Staz. 3: 14.III.90, leg. Leonardi, 1 f; idem, leg. Sas¬

si, 1 f. Staz. 4: 30.III.90, leg. Sassi, 1 f. Staz. 8, 14. III. 90,

leg. Leonardi, 2 ff 2 mm; idem. leg. Sassi, 5 ff 1 m.

Stethomostus fuliginosus (Schrank, 1781)

Corotipo: Asiatico-Europeo (ASE); introdotto in

Nord America.

Presenza in Italia: regioni settentrionali, Toscana,

Lazio, Abruzzo, Campania, Calabria.

Piante ospiti: diverse specie del genere Ranuncu-

lus.

Staz. 9: 15.VI.90, leg. Leonardi, 1 m.

Eutomostethus luteiventris (Klug, 1814)

Corotipo: Europeo (EUR); introdotto in Nord

America.

Presenza in Italia: regioni settentrionali, Toscana,

Lazio, Calabria.

Piante ospiti: Juncus effusus.

Staz. 9: 15. VI. 90. leg. Leonardi, 1 f.

Claremontia confusa (Konow, 1886)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: regioni settentrionali, Calabria;

citata da Costa (1894) anche di Sardegna sub Blen-

nocampa cinereipes (Hartig).

Piante ospiti: Rosacee dei generi Sanguisorba, Po¬

tentina, Fragaria.

Staz. 9: 30.III.90, leg. Sassi, 1 f.

Nematinae

Cladius pectinicomis (Geoffroy, 1785)

Corotipo: Olartico (OLA).

Presenza in Italia: regioni settentrionali, Toscana,

Sardegna; probabilmente diffuso in tutto il Paese, ma

i molti dati esistenti in letteratura possono riferirsi al-

) l’affine C. difformis (Panzer, 1799).

Piante ospiti: Rosacee dei generi Filipendula, Fra¬

garia, Rosa, Sanguisorba ; forse Lamiastrum galeob-

dolon.

Staz. 1: 10.X.91, leg. Sassi, 1 f. Staz 9: 30.III.90, leg.

Sassi, 1 f; 15.VI.90, leg. Leonardi, 1 f.

Tabella 1 - Tabella riassuntiva delle specie raccolte.

Considerazioni zoogeografiche

Il quadro corologico delle specie raccolte sul

Monte Barro indica una netta predominanza di ele¬

menti ad ampia distribuzione paleartica e la totale as¬

senza di specie mediterranee, come si può vedere dal¬

la tabella 2 e, con maggior evidenza, dalla figura 1,

dove i corotipi sono stati raggruppati per categorie

sintetiche.

250

FAUSTO PESARINI

Tabella 2 - Spettro corologico delle specie raccol¬

te. I corotipi sono stati definiti in base al lavoro di Vi¬

gna Taglianti et alii (1992).

Fig. 1 - Corotipi raggruppati per categorie sintetiche.

BIBLIOGRAFIA

Costa A., 1895 - Prospetto degli Imenotteri italiani, parte 3:Ten-

tredinidei e Siricidei. Atti Accad. Sci. fis. mat., Napoli, serie II,

7: 1-212.

Liston A.D., 1995 - Compendium of European Sawflies. Chala-

stos Forestry, Gottfrieding, 190 pp.

Masutti L. & Pesarini F., 1995 - Hymenoptera Symphyta. In: Mi-

nelli A., Ruffo S. & La Posta S. (eds.), Checklist delle specie

della fauna italiana. Calderini , Bologna, 92.

Pesaresi E, 1983 - Imenotteri Sinfiti del piano pedemontano in

Lombardia. I. Indagine faunistica (Hymenoptera Symphyta).

Boll. Ist. Zool. agr. Bachic.. Milano, ser. IL 17 (1982-83): 63-113.

Pesaresi F., 1989 - Studi sulle Tenthredininae (Hymenoptera

Tenthredinidae). Meni. Soc. ent. ital.,61 (1988): 337-3S8.

Pesaresi E, Campadelli G. & Crudele G., 1995 - Imenotteri

Sinfiti delle Foreste Demaniali Casentinesi (Materiali per una

sinfitofauna appenninica. I.). Boll. Ist. Ent. «G. Grandi», Bolo¬

gna, 50: 29-55.

Vigna Taglianti A., Audisio P.A., Belfiore C., Biondi M., Bo¬

logna M.A., Carpaneto G.M., De Biase A., De Felici S.,

Piattella E., Racheli T., Zapparoli M. & Zoia S., 1992 - Ri¬

flessioni di gruppo sui corotipi fondamentali della fauna W-pa-

leartica ed in particolare italiana. Biogeographia, 16: 159-179.

Fausto Pesarini: Museo Civico di Storia Naturale, Via De Pisis, 24 - 44100 Ferrara

Studi geobotanici ed entomofaunistici nel Parco Regionale del Monte Barro

Memorie della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano

Volume XXVII - Fascicolo II - 1997

Carlo Pesarmi

I Ragni (Arachnida Araneae) del Monte Barro

(Italia, Lombardia, Lecco)

Riassunto - Col presente lavoro sono forniti i dati relativi al popolamento araneologico del Monte Barro (Lecco), co¬

me risultato di una ricerca condotta negli anni 1989-1992 dal Museo di Storia Naturale di Milano col contributo del Con¬

sorzio Parco Monte Barro. Le raccolte sono state effettuate prevalentemente in 9 stazioni prative. Vengono analizzate le ca¬

ratteristiche biogeografiche della popolazione araneologica, e vengono segnalate 32 specie come nuove per la fauna lom¬

barda, fra le quali 5 ( Ceratinella scabrosa, Erigone autumnalis, Enoplognatha thoracica, Cheiracanthium montanum, Philo-

dromus praedatus) nuove per la fauna italiana.

Abstract - Spiders (Arachnida Araneae) from Monte Barro (Italy, Lombardy, Lecco).

In thè present work data concerning thè spider-fauna of thè Monte Barro are given, as result of a research carried out

by thè Naturai History Museum of Milano in thè years 1989-1992. Meadows have been chiefly investigated, with particular

regard to 9 sampling sites.The biogegraphic pattern of thè spider-population is analyzed; furthermore, 32 species are recor-

ded as new for thè Lombard fauna, 5 among which ( Ceratinella scabrosa, Erigone autumnalis, Enoplognatha thoracica, Chei¬

racanthium montanum, Philodromus praedatus ) are new for Italy.

Key words: Monte Barro, Araneae, geographic distribution.

Negli anni 1989-1992 il Museo Civico di Storia Na¬

turale di Milano ha condotto una ricerca entomofau-

nistica nell’area del Monte Barro (Lombardia, Lecco)

col contributo del Consorzio Parco. Per quanto ri¬

guarda la fauna araneologica, alle raccolte effettuate

da Davide Sassi e Carlo Leonardi sono da aggiunger¬

si quelle prodotte, nell’ambito di un lavoro di tesi di

laurea da me coordinato, dalla Dr.ssa Monica Aureg-

gi. Il quadro complessivo così ottenuto è discreta¬

mente ricco, anche se verosimilmente non del tutto

completo. Si riscontrano infatti delle lacune per quan¬

to riguarda la fauna del terreno, sicuramente molto

più abbondante di quanto non appaia dall’elenco qui

fornito; ciò va imputato alla modalità delle ricerche

condotte, indirizzate essenzialmente ad un monito-

raggio della fauna legata alla vegetazione. A dispetto

di tale lacuna, peraltro, i dati ottenuti sono di indub¬

bio interesse, ed hanno condotto alla segnalazione di

32 specie nuove per la Lombardia, fra cui 5 nuove per

la fauna italiana ( Ceratinella scabrosa, Erigone au¬

tumnalis, Enoplognatha thoracica, Cheiracanthium

montanum, Philodromus praedatus). Tale segnalazio¬

ne viene fornita in modo generico per l’Italia setten¬

trionale nella check-list delle specie italiane da me re¬

centemente pubblicata (Pesarmi, 1995); dati più det¬

tagliati, limitatamente alle specie di Linyphiidae della

sottofamiglia Erigoninae sono invece da me forniti in

un’altra pubblicazione attualmente in stampa.

»

Osservazioni sulle stazioni di raccolta

Le raccolte sono state effettuate prevalentemente

in nove stazioni (staz.1-9) caratterizzate da una forte

presenza prativa; ulteriori stazioni di raccolta sono

state riunite, nel quadro riassuntivo (Tabella 1), in

una sorta di stazione cumulativa indicata con il nu¬

mero 10.

Qui di seguito è data una breve descrizione delle

stazioni 1-9; esse corrispondono più o meno a quelle

della ricerca generale ma hanno quasi sempre confi¬

ni più ampi e in alcuni casi sono fisionomicamente

più varie. Per ogni stazione sono indicati i taxa esclu¬

sivi (specificità). Le specie contrassegnate da un *,

pur essendo state rinvenute in una sola delle nove

stazioni considerate, risultano presenti in uno o più

dei biotopi riuniti al numero 10.

Stazione 1: Località Piani di Barra, 610 m. esp. W,

interessata da scavi archeologici (Grande Edificio). E

caratterizzata da una consistente presenza di prato

falciabile che indica un’attività di foraggio residua.

Specificità: Clubiona terrestris*.

Stazione 2: Località Piani di Barra, 600 m, esp. W,

interessata da scavi archeologici (Edificio II). Si trat¬

ta di una prateria in cui è stata abbandonata la ge¬

stione a foraggio ed è presente un leggero mantello

con forte copertura di Geranium sanguineum. Nella

stessa area si collocano boschi moderatamente ter¬

mofili con Quercus pubescens, Ostrya carpinifolia e

Corylus avellana.

Specificità: Aculepeira ceropegia, Porrhomma

pygmaeum, Episinus truncatus*, Trochosa ruricola *,

Xerolycosa nemoralis*, Xysticus bufo * Brigittea la-

tens, Heliophanus aeneus.

Stazione 3: Conca prativa a monte del Monumen¬

to dell’Alpino, 630 m, esp. W. Vi si nota la convivenza

di elementi di prateria, elementi di prato falciabile ed

elementi di disturbo marginale.

252

CARLO PESARINI

Specificità: Araneus sturmi, Ar. triguttatus, Meione-

ta rurestris, Cheiracanthium montanum.

Stazione 4: Località S. Michele, pendio in prossi¬

mità del sentiero per Pian Sciresa, 325 m, esp. E. Su

una base di Mesobromion è in pieno sviluppo il pra¬

to falciabile, che qui presenta il carattere oligo-meso-

trofico.

Stazione 5: Località Pian Sciresa, 435 m, esp. NE.

Prevalenza di prateria arida a Brachypodium rupestre

ssp. caespitosum , con montarozzi residuali a brughie¬

ra. La continuità della prateria è interrotta qua e là da

Betula penduta, Corylus avellana e alberi caratteristi¬

ci di boschi moderatamente termofili ( Quercus pube-

scens, Ostrya carpinifolia).

Specificità: A raneus alsine, Ero aphana, Ero furca-

ta, Ceratinella scabrosa , Erigone autumnalis, Dipoena

melanogaster*, Arctosa perita , Par dosa hortensis, Par-

dosa riparia, Nigma flavescens, Zelotes praeficus, Phi-

lodromus praedatus, Xysticus ninnii, Aelurillus v-insi-

gnitus, Marpissa nivoyi, Philaeus chrysops.

Stazione 6: Superfici prative lungo il sentiero del¬

la “Cresta occidentale” che dall’edificio dell’ex sana¬

torio sale alla vetta, partendo da una quota di circa

750 m, esp. S. Prateria con parziale affioramento roc¬

cioso. All’inizio appare fortemente cespugliata e in

via di chiusura, con forte influsso dell’elemento pre-

nemorale verso un Quercetum pubescenti s.L; più in

alto dominano i molinieti e i seslerieti.

Specificità: Lepthyphantes tenuis, Peponocranium

orbiculatum, Salticus scenicus.

Stazione 7: Località Fornaci Villa, in prossimità

deH'impluvio della Val Faè, 275 m, esp. NW. Superfi¬

cie prativa terrazzata all’interno del bosco mesofilo,

molto simile a quella della stazione 8 ma più aperta e

con qualche elemento in più di Mesobromion.

Specificità: Lepthyphantes flavipes*,

Stazione 8: Località Fornaci Villa, in prossimità

dell’impluvio della Val Faè, 305 m, esp. NW. Superfi¬

cie terrazzata, irregolarmente gestita e contornata da

un bosco con notevoli contrassegni mesofili, in con¬

seguenza dell’esposizione fresca e di un maggiore svi¬

luppo del suolo.

Specificità: Ozyptila randa.

Stazione 9: Località Ca’ di Sala, 226 m, sulla riva set¬

tentrionale del bacino di Oggiono del Lago di Annone.

Vi si evidenziano tre aspetti essenziali: 1) il canneto

con accenni di aggruppamenti a Iris pseudoacorus , ele¬

menti di magnocariceto e residui di boscaglia ripariale.

2) il prato umido oligotrofico ( Molinion coeruleae). 3)

vegetazione erbacea perenne e disorganizzata, al mar¬

gine superiore della stazione, riconducibile alle classi

Artemisietea vulgaris e Plantaginetea majoris.

Specificità: Tetragnatha extensa, Hypsosinga heri*,

Gnathonarium dentatum*, Par dosa prativaga, Agele-

na labyrinthica, Clubiona phragmitis, Misumenops tri-

cuspidatus, Runcinia laterali, Xysticus ulmi.

Elenco delle specie raccolte

In tale elenco si è seguito l’ordine adottato nella

redazione della check-list delle specie italiane (Pesa¬

rmi, 1995). Si è quindi seguito un ordine sistematico

nella trattazione delle varie famiglie, mentre all’inter¬

no di ogni singola famiglia le specie vengono elenca¬

te in ordine alfabetico.

Si è colta l’occasione, per alcune specie, di fornire

illustrazioni degli organi genitali, sempre molto utili

per l’identificazione, quando di tali organi non è age¬

volmente disponibile, in letteratura, un’iconografia

adeguata. Gli esemplari raffigurati, salvo contraria in¬

dicazione, provengono dalle raccolte effettuate nel¬

l’area del M. Barro.

Atypidae

Atypus affinis (Sulzer)

Corotipo: europeo (EUR).

Presenza in Italia: Lombardia e Toscana.

Un esemplare giovanile raccolto nell’alneto lungo

il torrente della Val Faè (14. III. 1990, lg. Aureggi).

Dysderidae

Dasumia taeniifera Thorell

Corotipo: Alpino appenninico.

Presenza in Italia: Lombardia, Emilia-Romagna,

Toscana, Lazio.

Alcune 9 9 raccolte nelle staz. 2 e 5.

Tetragnathidae

Pachygnatha clercki (Sundevall)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Piemonte, Lombardia, Veneto,

Trentino-Alto Adige, Friuli-Venezia Giulia, Emilia-

Romagna, Toscana, Umbria, Calabria.

Un S raccolto nell’alneto lungo il torrente della

Val Faè (14.III.1990, lg. Aureggi).

Pachygnatha degeeri (Sundevall)

Corotipo: Paleartico (PAL).

Presenza in Italia: Liguria, Lombardia, Veneto,

Trentino-Alto Adige, Friuli-Venezia Giulia, Emilia-

Romagna, Toscana, Marche, Umbria, Lazio, Campa¬

nia, Calabria.

Alcuni esemplari raccolti nelle staz. 2 e 5 e nei bo¬

schi della Val Faè.

Tetragnatha extensa (Linneo)

Corotipo: Olartico (OLA).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

2 8 <5 e 3 9 9 raccolti nella staz. 9.

Metidae

Meta segmentata (Clerck)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Numerosi esemplari raccolti nelle staz. 3, 5 e 7, nei

boschi della Val Faè e nella zona ad Ovest dei Piani di

Barra.

Araneidae

Aculepeira ceropegia (Walckenaer)

Corotipo: Paleartico (PAL).

Presenza in Italia: gran parte d’Italia, Sicilia, Sar¬

degna.

Un esemplare giovanile raccolto nella staz. 2

(12.VI.1991,lg. Aureggi).

Agalenatea redii (Scopoli)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Alcune 9 9 raccolte nelle staz. 2 e 5 e un esem-

I RAGNI ( ARACHNIDA ARANEAE) DEL MONTE BARRO (ITALIA, LOMBARDIA. LECCO)

253

piare giovanile raccolto nell'alneto lungo il torrente

della vai Faè.

Araneus disine (Walckenaer)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Piemonte, Lombardia, Veneto.

Una $ raccolta nella staz. 5 (20.IX.1989,lg. Auriggi).

Araneus sturmi (Hahn)

Corotipo: Europeo (EUR).

Presenza in Italia: Liguria, Piemonte, Lombardia,

Veneto, Trentino-Alto Adige, Emilia-Romagna, To¬

scana, Lazio, Campania, Puglia, Calabria.

Un 8 raccolto nella staz. 3 (13.IX.1990, lg. Leo¬

nardi).

Araneus triguttatus (Fabricius)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Lombardia, Veneto, Trentino- Al¬

to Adige, Emilia-Romagna, Umbria, Lazio, Abruzzi.

Un 8 raccolto nella staz. 3 (13. IX. 1990, lg. Leo¬

nardi).

Araniella cucurbitina (Clerck)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Alcuni esemplari raccolti nelle staz. 2, 5 e 6.

Argiope bruennichi (Scopoli)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Alcuni esemplari, per lo più giovanili, raccolti nel¬

le staz. 5 e 6 ed in prossimità dell’Osservatorio orni¬

tologico.

Cercidia prominens (Westring)

Corotipo: Olartico (OLA).

Presenza in Italia: Lombardia, Veneto, Trentino-

Alto Adige, Emilia-Romagna, Toscana, Umbria,

Abruzzi, Puglia, Calabria, Sardegna.

Alcuni esemplari raccolti nelle staz. 5 e 8 e nei bo¬

schi della Val Faè.

Cyclosa conica (Pallas)

Corotipo: Olartico (OLA).

Presenza in Italia: Tutta Italia, Sicilia, Sardegna.

Alcuni esemplari raccolti nelle stazioni 2 e 5 e 1 $

raccolta nei boschi della vai Faè (23.V.1991 lg. Sassi).

Gibbaranea bituberculata (Walckenaer)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Numerosi esemplari raccolti nelle staz. 2, 3, 5, 6 e

7 e nei boschi della Val Faè.

Hypsosinga heri (Hahn)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Italia settentrionale, Emilia-Ro¬

magna, Toscana, Umbria, Calabria, Sicilia.

Alcuni esemplari raccolti nella staz. 9 e nei boschi

della Val Faè.

Hypsosinga sanguinea (Koch)

Corotipo: Europeo (EUR).

Presenza in Italia: Trentino- Alto Adige, Friuli-Vene¬

zia Giulia, Emilia-Romagna, Toscana, Marche, Lazio,

Calabria. La specie risulta nuova per la Lombardia.

Alcuni esemplari raccolti nelle stazioni 4 e 5.

Larinioides comutus (Clerck)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Alcuni esemplari raccolti nelle stazioni 4 e 9.

Mangora acalypha (Walckenaer)

Corotipo: W-Paleartico (WPA).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Numerosissimi esemplari raccolti nelle staz. 2, 3, 5,

6, 7 e 9, nei boschi della Val Faè, presso l’Osservato¬

rio ornitologico e ad Ovest dei Piani di Barra.

Neoscona adiantum (Walckenaer)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Numerosi esemplari raccolti nelle staz. 2, 5, 6 e 9 e

nei pressi dell’Osservatorio ornitologico.

Zilla diodia (Walckenaer)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Alcuni esemplari raccolti nelle staz. 5 e 6 e ad

Ovest dei Piani di Barra.

Mimetidae

Ero aphana (Walckenaer)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: Liguria, Piemonte, Lombardia,

Veneto, Friuli-Venezia Giulia, Emilia-Romagna, To¬

scana, Marche, Umbria, Calabria.

Un esemplare giovanile raccolto nella staz. 5

(23.V.1991, lg. Auriggi).

Ero furcata (Villers)

Corotipo: Europeo (EUR).

Presenza in Italia: Lombardia, Trentino-Alto Adi¬

ge, Toscana.

Una 2 raccolta nella staz. 5 (28.V.1990,lg. Aureggi).

Linyphiidae

Ceratinella scabrosa (Pickard-Cambridge)

Corotipo: Centroeuropeo (CEU).

Presenza in Italia: da me recentemente indicata,

sulla scorta del presente reperto, in occasione della

compilazione della check-list delle specie italiane del¬

l’ordine (Pesarmi 1995).

Un 8 raccolto nella staz. 5 (28.V.1990, lg. Aureggi).

Osservazioni: il presente reperto è l’unico noto

per la fauna italiana.

Cresmatoneta mutinensis (Canestrini), Fig. 1, 2

Corotipo: S-Europeo (SEU).

Presenza in Italia: Liguria, Lombardia, Emilia-Ro¬

magna, Toscana, Umbria, Puglia, Calabria.

Alcuni esemplari raccolti nelle stazioni 3 e 9.

Erigone autumnalis Emerton

Corotipo: Olartico (OLA).

Presenza in Italia: da me recentemente indicata,

sulla scorta del presente reperto, in occasione della

compilazione della check-list delle specie italiane del¬

l’ordine (Pesarini 1995).

2 8 8 raccolti nella stazione 3 (10.VI.1991) e 5

8 8 raccolti nella staz. 5 (30.V.1989, lg. Leonardi).

Osservazioni: fino a pochi anni fa, questa specie

era nota solo della fauna neartica; di recente Hànggi

254

CARLO PESARINI

(1990) l’ha segnalata del Canton Ticino (M. Genero¬

so e M. S.Giorgio), quindi di un’area assai prossima al

M. Barro. Sembrerebbe peraltro verosimile che l’ef¬

fettiva diffusione della specie in Europa, pur se tutto¬

ra pressoché ignota, sia notevolmente più ampia.

Erigone dentipalpis (Wider)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Piemonte, Lombardia, Veneto,

Friuli-Venezia Giulia, Emilia-Romagna, Toscana, La¬

zio, Campania.

Alcuni esemplari raccolti nelle staz. 5 e 9 e nell’al-

neto lungo il torrente della Val Faè.

Gncitìionarium dentatimi (Wider)

Corotipo: Paleartico (PAL).

Presenza in Italia: Piemonte, Friuli-Venezia Giu¬

lia, Emilia-Romagna, Toscana. La specie risulta nuo¬

va per la Lombardia.

Alcuni esemplari raccolti nella staz. 9 e nell’alne-

to lungo il torrente della Val Faè.

Hylyphantes nigritus (Simon)

Corotipo: Europeo (EUR).

Presenza in Italia: Piemonte, Friuli-Venezia Giu¬

lia, Toscana. La specie risulta nuova per la Lombar¬

dia.

Alcuni esemplari raccolti nelle staz. 2 e 9 e nell’al-

neto lungo il torrente della Val Faè.

Lepthyphantes flavipes (Blackwall)

Corotipo: Europeo (EUR).

Presenza in Italia: Trentino- Alto Adige, Campa¬

nia.

Alcuni esemplari raccolti nella staz. 7 (3 S S e 9

9 9 , 9.V.1990, lg. Aureggi) e nei boschi della Val Faè

(1 9, 16.V.1990, lg. Aureggi).

Osservazioni: in realtà questa specie, che risulta

nuova per la Lombardia, è assai comune e diffusa, al¬

meno nell’Italia settentrionale, a dispetto dell’inspie-

gabile scarsità di precedenti segnalazioni.

Personalmente, mi è anche nota delle seguenti lo¬

calità: Liguria: Finale Ligure (15.V.88, lg. Sciaky, 1 S ).

Piemonte: Crissolo (30.IV.1983, lg. Sciaky, 1 9); Ro-

vasenda (prov. Vercelli, Vili. 1984, lg. Gozzi, 1 1).

Lombardia: Dumenza (prov. Varese, 12.VII.1987, lg.

Zanon, 19); Val Fredda (prov. Varese, 4. X. 1983, lg.

Baratelli, 1 9); Bernate Ticino (prov. Milano,

XII.1989, 1.1990, 11.1990, lg. Pasquetto, 7 SS e 5 9 9);

Monza Parco (IX. 1985, lg. Sciaky, 1 S e 2 9 9 ); Mon-

torfano (prov. Brescia, 11.1991, 4 S S e 6 9 9 , lg. Ghi-

lardi). Veneto: M. Cesen (prov. Treviso, 2.V.1988, lg.

Zanon, 19); Col Perer (prov. Belluno, 25. VI. 1988, lg.

Zanon, 1 d e 1 9); Cima di Campo (prov. Belluno,

25. VI. 1988, 2 SS e 2 99). Friuli-Venezia Giulia:

Grotta Ercole presso Gabrovizza (prov. Trieste,

18. Vili. 1986, lg. Zanon, 19). Emilia- Romagna: Ba-

dagnano (prov. Piacenza, 24.III.1982, lg. Pavesi, 1 d).

Lepthyphantes tenuis (Blackwall)

Corotipo: Europeo (EUR).

Presenza in Italia: Veneto, Friuli-Venezia Giulia,

Emilia-Romagna, Toscana, Umbria, Marche, Lazio,

Campania, Puglia, Calabria. La specie non risultava

segnalata per la Lombardia.

Una 9 raccolta nella staz. 6 (11. VI. 1990, lg. Au¬

reggi)

Linyphia hortensis Sundevall

Corotipo: Centroasiatico-Europeo (CAE).

Presenza in Italia: Piemonte, Lombardia, Veneto,

Trentino-Alto Adige, Friuli-Venezia Giulia, Emilia-

Romagna, Toscana, Umbria, Marche, Campania, Ca¬

labria.

Numerosi esemplari raccolti nelle staz. 2, 3, 5 e 6 e

nei boschi della Val Faè.

Meioneta rurestris (Koch)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: Veneto, Trentino-Alto Adige,

Friuli-Venezia Giulia, Emilia-Romagna, Toscana,

Marche, Puglia. La specie risulta nuova per la Lom¬

bardia.

Una 9 raccolta nella staz. 3 (14.III.1990, lg. Leo¬

nardi).

Microlinyphia pusilla (Sundevall)

Corotipo: Olartico (OLA).

Presenza in Italia: Italia Settentrionale, Emilia-

Romagna, Toscana, Umbria, Calabria.

Alcuni esemplari raccolti nelle staz. 2, 3 e 5, nel-

l’alneto lungo il torrente della Val Faè e presso l’Os¬

servatorio ornitologico.

Minicia marginella (Wider)

Corotipo: Europeo (EUR).

Presenza in Italia: Trentino- Alto Adige. La specie

risulta nuova per la Lombardia.

Alcuni esemplari raccolti nelle staz. 2, 5, 6 e 9 e ad

Ovest dei Piani di Barra.

Nematogmus sanguinolentus (Walckenaer)

Corotipo: Europeo (EUR).

Presenza in Italia: Lombardia, Veneto, Trentino-

Alto Adige, Emilia-Romagna, Toscana, Lazio, Puglia.

Alcuni esemplari raccolti nelle staz. 3, 6 e 9 e pres¬

so l’Osservatorio ornitologico.

Neriene pettata (Wider)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Trentino- Alto Adige, Friuli-Ve¬

nezia Giulia, Emilia-Romagna, Campania, Puglia,

Calabria. La specie risulta nuova per la Lombardia.

Una 9 raccolta nei boschi della Val Faè

(16.V.1990, lg. Aureggi).

Peponocranium orbiculatum (Pickard-Cambridge)

Corotipo: Europeo (EUR).

Presenza in Italia: Trentino-Alto Adige. La specie

risulta nuova per la Lombardia.

Una 9 raccolta nella staz. 6 (11. VI. 1990, lg. Au¬

reggi).

Porrhomma pygmaeum (Blackwall)

Corotipo: Centroeuropeo (CEU).

Presenza in Italia: Veneto. La specie risulta nuova

per la Lombardia.

Una 9 raccolta nella staz. 2 (23.V.1991, lg. Aureg¬

gi)-

Walckenaeria antica (Wider)

Corotipo: Europeo (EUR).

Presenza in Italia: Trentino-Alto Adige. La specie

risulta nuova per la Lombardia.

Alcuni esemplari raccolti nelle staz. 2, 3, 4 e 7.

I RAGNI (ARACHNIDA ARANEAE) DEL MONTE BARRO (ITALIA, LOMBARDIA, LECCO)

255

Fig. 1-4 - 1-2) Cresmatoneta mutinensis (Canestrini); 1) pedipalpo 8 in visione laterale; 2) id., epigino $ ; 3-4) Cheiracanthìum

elegans Thorell; 3) pedipalpo 8 in visione laterale; 4) Cheiracanthìum montanum Koch, pedipalpo 8 in visione laterale.

Theridiidae

Achaearanea lunata (Clerck)

Corotipo: Europeo (EUR).

Presenza in Italia; Italia settentrionale, Emilia-Ro¬

magna, Toscana, Campania, Calabria, Sicilia.

Un 8 raccolto ad Ovest dei Piani di Barra

(25.VI.1991, lg. Aureggi).

Crustuliha guttata (Wider)

Corotipo: Olartico (OLA).

Presenza in Italia: Veneto, Trentino-Alto Adige,

Friuli-Venezia Giulia, Emilia-Romagna, Campania,

Puglia. La specie risulta nuova per la Lombardia.

Alcuni esemplari raccolti nelle staz. 2, 4, 5 e 6.

Dipoena melanogaster (Koch)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: Trentino-Alto Adige, Friuli-Ve¬

nezia Giulia, Emilia-Romagna, Marche, Lazio, Italia

meridionale, Sicilia. La specie risulta nuova per la

Lombardia.

Alcuni esemplari raccolti nella staz. 5 e nei boschi

della Val Faè.

Enoplognatha ovata (Clerck)

Corotipo: Olartico (OLA).

Presenza in Italia: Tutta Italia, Sicilia, Sardegna.

Numerosi esemplari raccolti nelle staz. 2, 5 e 9, nei

boschi della Val Faè e ad Ovest dei Piani di Barra.

Enoplognatha thoracica (Hahn)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: da me recentemente indicata in

occasione della compilazione della check-list delle

specie italiane dell’ordine (Pesarmi, 1995).

Alcuni esemplari raccolti nelle stazioni 3 e 4 e

un 8 nei boschi della Val Faè (16.V.1990, lg. Au¬

reggi).

Osservazioni: Questa specie, di cui non esistono in

letteratura altre indicazioni per la fauna italiana, mi è

comunque nota anche di un’altra località lombarda

(Raffa del Garda in provincia di Brescia, 24.V.1991,

un G, lg. Cauda), di Veneto (Ponte Fiorio in provincia

di Verona, un G, lg. Ferri) e Sicilia (Torre Montaspro

in provincia di Palermo, 4.VII.1991, 4 $ $ , lg. Pesari-

ni & Sabbadini).

Episinus truncatus Latreille

Corotipo: Europeo (EUR).

Presenza in Italia: Italia settentrionale, Emilia-Ro¬

magna, Marche, Umbria, Campania, Calabria, Sarde-

gna.

Alcuni esemplari raccolti nella staz. 2 e nei boschi

della Val Faè.

Euryopis flavomaculata (Koch)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Trentino-Alto Adige, Friuli-Ve¬

nezia Giulia, Emilia-Romagna, Toscana, Marche,

Umbria, Lazio, Campania. La specie risulta nuova

per la Lombardia.

Un 8 raccolto presso l’Osservatorio ornitologico

(16.V.1990, lg. Aureggi).

Neottiura bimaculata (Linneo)

Corotipo: Sibirico-Europeo (SIE)

Presenza in Italia: Lombardia, Veneto, Trentino-

Alto Adige, Friuli-Venezia Giulia, Emilia-Romagna,

Toscana, Marche, Umbria, Lazio, Campania, Cala¬

bria, Sicilia.

Alcuni esemplari raccolti nelle staz. 2, 5 e 6, nei

boschi della Val Faè e ad Ovest dei Piani di Barra.

256

CARLO PESARINI

Theridion nigrovariegatum Simon

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: Emilia-Romagna, Marche,

Campania, Calabria, Sicilia. La specie risulta nuova

per la Lombardia.

Alcuni esemplari raccolti nelle staz. 5 e 6, presso

l’Osservatorio ornitologico e ad Ovest dei Piani di

Barra.

Theridion simile Koch

Corotipo: Europeo (EUR).

Presenza in Italia: Liguria, Piemonte, Trentino- Al¬

to Adige, Veneto, Friuli-Venezia Giulia, Toscana,

Marche, Umbria, Lazio, Abruzzo, Campania, Basili¬

cata, Calabria, Sicilia. La specie risulta nuova per la

Lombardia e mi è nota anche di Emilia (Badagnano

in provincia di Piacenza, diversi esemplari di diverse

date, lg. Pavesi e Pesarini).

3 6 6 e 4 9 2 raccolti nelle stazioni 2, 5 e 6, lg. Bo-

nini.

Pisauridae

Pisaura mirabilis (Clerck)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Numerosissimi esemplari (fra cui però solamente

6 6 6 e 9 $ $ adulti) raccolti nelle staz. 1, 2, 3, 5, 6, 7,

8 e 9 e presso l’Osservatorio ornitologico.

Osservazioni: gli adulti rinvenuti sono da attribui¬

re alla specie intesa in senso stretto, e non a qualcuna

delle specie strettamente affini solo recentemente

prese in considerazione nella letteratura; nessuna in¬

dicazione precisa in tal senso, ovviamente, può essere

fornita per i numerosi giovani.

Lycosidae

Arctosa perita (Latreille)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: Italia settentrionale e centrale,

Puglia, Calabria, Sardegna.

Un 6 raccolto nella staz. 5 (28.V.1990, lg. Aureggi).

Aulonia albimana (Walckenaer)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: Italia settentrionale, Emilia-Ro¬

magna, Toscana.

Alcuni esemplari raccolti nelle staz. 2 e 5.

Pardosa hortensis (Thorell)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: Italia settentrionale, Emilia-Ro¬

magna, Toscana, Campania, Puglia, Basilicata, Calabria.

Un 6 raccolto nella staz. 5 (28.V.1990, lg. Aureggi).

Pardosa lugubris (Walckenaer)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Italia settentrionale, Emilia-Ro¬

magna, Toscana, Campania, Puglia, Basilicata, Cala¬

bria.

Alcuni esemplari raccolti nelle staz. 5 e 6, nei bo¬

schi della Val Faè e presso l’Osservatorio ornitologico.

Pardosa prativaga (Koch)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Piemonte, Emilia-Romagna,

Toscana, Campania, Calabria. La specie risulta nuova

per la Lombardia.

Una 9 raccolta nella staz. 9 (15.VI.1990, lg. Leo¬

nardi).

Pardosa riparia (Koch)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Piemonte, Lombardia, Veneto,

Friuli-Venezia Giulia, Emilia-Romagna, Calabria.

Un 6 proveniente dalla staz. 5 (23.V.1991, lg. Au¬

reggi)-

Trochosa ruricola (Degeer)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: Italia settentrionale, Emilia-Ro¬

magna, Toscana, Umbria, Puglia, Calabria, Sicilia.

Alcuni esemplari raccolti nella staz. 2 e presso

l’Osservarorio ornitologico.

Xerolycosa nemoralis (Westring)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Lombardia, Toscana, Calabria.

Alcuni esemplari raccolti nella staz. 2 e ad Ovest

dei Piani di Barra.

Agelenidae

Agelena labyrinthica (Clerck)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Un esemplare giovanile raccolto nella staz. 9

(22.V.1991, lg. Leonardi).

Dyctinidae

Brigittea latens (Fabricius)

Corotipo: W-Paleartico (WPA).

Presenza in Italia: Piemonte, Veneto, Friuli-Vene¬

zia Giulia, Emilia-Romagna, Toscana, Umbria, Cam¬

pania, Puglia, Calabria. La specie risulta nuova per la

Lombardia.

5 2 9 raccolte nella staz. 2 (16.V.1991,lg. Aureggi).

Nigma flavescens (Walckenaer)

Corotipo: Europeo (EUR).

Presenza in Italia: Liguria, Lombardia, Emilia-Ro¬

magna, Toscana, Lazio.

Un S raccolto nella staz. 5 (25.VI.1991,lg. Aureggi).

Nigma puella (Simon)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: Lombardia, Emilia-Romagna,

Toscana, Umbria.

Una 9 raccolta nei boschi della Val Faè

(30.V.1990, lg. Aureggi).

Anyphaenidae

Anyphaena accentuata (Walckenaer)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia, Sardegna.

Una 2 raccolta nei boschi della Val Faè

(16.V.1990, lg. Aureggi).

Clubionidae

Cheiracanthium elegans Thorell, Fig. 3

Corotipo: Europeo (EUR).

Presenza in Italia: Veneto, Emilia-Romagna, To-

I RAGNI (ARACHNIDA ARANEAE) DEL MONTE BARRO (ITALIA. LOMBARDIA, LECCO)

257

scana, Lazio, Campania, Calabria. La specie risulta

nuova per la Lombardia.

Una 9 raccolta nei sottoboschi della Val Faè

(16.V.1990, lg. Leonardi).

Cheiracanthium montanum Koch, Fig. 4

Corotipo: Centroeuropeo (CEU).

Presenza in Italia: da me recentemente indicata,

sulla scorta del presente reperto, in occasione della

compilazione della check-list delle specie italiane del¬

l’ordine (Pesarini 1995).

Un 6 raccolto nella staz. 3 (9.V.1990, lg. Leonar¬

di).

Clubìona neglecta Pickard-Cambridge

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Friuli-Venezia Giulia, Emilia-

Romagna, Puglia. La specie risulta nuova per la Lom¬

bardia.

Una $ raccolta nella staz. 2 (15.IV.1989, lg. Leo¬

nardi) e una $ nella staz. 6 (12. VI. 1991, lg. Aureggi).

Clubiona phragmitis Koch

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Italia settentrionale, Emilia-Ro¬

magna, Umbria, Marche, Basilicata.

Un 6 e una 9 raccolti nella staz. 9 (11. VI.1991, lg.

Aureggi).

Clubiona terrestris Westring

Corotipo: Europeo (EUR).

Presenza in Italia: Liguria, Veneto, Trentino- Alto

Adige, Umbria, Lazio, Campania, Calabria. La specie

risulta nuova per la Lombardia.

Un 6 raccolto nella staz. 1 (10.VI.1991, lg. Leo¬

nardi) e una 9 raccolta nei boschi della Val Faè

(16.V.1990, lg. Aureggi).

Gnaphosidae

Zelotes praeficus (Koch)

Corotipo: Centroasiatico-Europeo (CAE).

Presenza in Italia: Veneto, Trentino-Alto Adige,

Friuli-Venezia Giulia, Emilia-Romagna, Toscana,

Marche, Calabria. La specie risulta nuova per la Lom¬

bardia.

Un 6 raccolto nella staz. 5 (28.V.1990, lg. Aureg¬

gi)-

Eusparassidae

Micrommata virescens (Clerck)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: Italia settentrionale e centrale,

Campania, Calabria, Sardegna.

Nunerosi esemplari, in prevalenza giovanili, rac¬

colti nelle staz. 2, 5, 7 e 9, nei boschi della Val Faè e

presso l’Osservatorio ornitologico.

Philodromidae

) Philodromus aureolus (Clerck)

Corotipo: Olartico (OLA).

Presenza in Italia: Piemonte, Lombardia, Veneto,

Trentino-Alto Adige, Emilia-Romagna, Marche,

Campania, Puglia, Calabria, Sicilia.

Alcuni esemplari raccolti nelle staz. 5, 6 e 9.

Philodromus cespitum (Walckenaer)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: Veneto, Trentino-Alto Adige,

Friuli-Venezia Giulia, Emilia-Romagna, Toscana,

Umbria, Lazio, Campania, Puglia, Sicilia. La specie ri¬

sulta nuova per la Lombardia.

Alcuni esemplari raccolti nelle staz. 6 e 9.

Philodromus dispar Walckenaer

Corotipo: Europeo (EUR).

Presenza in Italia: Emilia-Romagna, Umbria, La¬

zio. La specie risulta nuova per la Lombardia.

Numerosi esemplari raccolti nelle staz. 3, 5, 7 e 8 e

nei boschi della Val Faè.

Philodromus praedatus Pickard-Cambridge

Corotipo: Europeo (EUR).

Presenza in Italia: da me recentemente indicata in

occasione della compilazione della check-list delle

specie italiane dell’ordine (Pesarini 1995).

Una 9 raccolta nella staz. 5 (28. V. 1990, lg. Aureg¬

gi)-

Osservazioni: solo recentemente rivalutata, questa

specie non risultava precedentemente segnalata d’I¬

talia, dove è in realtà abbastanza diffusa; oltre che del

M. Barro mi è infatti nota delle seguenti località: Pie¬

monte: Roncasso (prov. Torino, VII. 1981, lg. Giachi-

no, 1 9). Lombardia: Piazzatorre (prov. Bergamo,

14.IX.1989, lg. Camelli, 19). Basilicata: M. Pollino

(prov. Potenza, VI.1991, lg. Sabbadini, 19). Sicilia:

Piano Zucchi (prov. Palermo, 2/4. VII. 1991, lg. Pesari¬

ni & Sabbadini, 2 9 9).

Tibellus oblongus (Walckenaer)

Corotipo: Olartico (OLA).

Presenza in Italia: Italia settentrionale, Emilia-Ro¬

magna, Lazio, Campania, Calabria.

Alcuni esemplari raccolti nelle staz. 2, 3, 5, 6 e 9 e

nei dintorni dell’Osservatorio ornitologico.

Thomisidae

Heriaeus hirtus (Latreille)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: Liguria, Piemonte, Lombardia,

Veneto, Emilia-Romagna, Toscana, Umbria, Campa¬

nia, Puglia, Calabria, Sicilia, Sardegna.

Numerosi esemplari raccolti nelle staz. 2, 5 e 6, nei

boschi della Val Faè e presso l’Osservatorio ornitolo¬

gico.

Misumena vatia (Clerck)

Corotipo: Olartico (OLA).

Presenza in Italia: tutta Italia, Sicilia.

Numerosi esemplari raccolti nelle staz. 2, 3, 5, 6, 7,

8 e 9, nei boschi della Val Faè, presso l’Osservatorio

ornitologico e ad Ovest dei Piani di Barra.

Misumenops tricuspidatus (Fabricius)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: Liguria, Piemonte, Lombardia,

Veneto, Emilia-Romagna, Toscana.

Numerosi esemplari raccolti in maggio e giugno

nella staz. 9.

Ozyptila rauda Simon

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Piemonte, Friuli-Venezia Giu-

258

CARLO PESARINI

Ha, Emilia-Romagna, Puglia. La specie risulta nuova

per la Lombardia.

Un 6 raccolto nella staz. 8 ( 16. V. 1990, lg. Aureg-

gi)-

Runcinia lateralis (Koch)

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: Italia settentrionale e centrale,

Calabria, Sicilia, Sardegna.

Numerosi esemplari raccolti nella staz. 9 in mag¬

gio e giugno.

Synaema globosum (Fabricius)

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Numerosi esemplari raccolti nelle staz. 1, 2, 3, 6 e

9, nei boschi della Val Faè, presso POsservatorio or¬

nitologico e ad Ovest dei Piani di Barra.

Thomisus onustus Walckenaer

Corotipo: Paleartico (PAL).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Numerosi esemplari raccolti nelle staz. 2, 5 e 6, ad

Ovest dei Piani di Barra e presso POsservatorio orni¬

tologico.

Tmarus piger (Walckenaer)

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: Italia settentrionale e centrale,

Campania.

Numerosi esemplari raccolti nelle staz. 2, 3, 5, 6, 7

e 8, nei boschi della Val Faè e presso POsservatorio

ornitologico.

Xysticus acerbus Thorell

Corotipo: Asiatico-Europeo (ASE).

Presenza in Italia: Lombardia, Veneto, Friuli-Ve¬

nezia Giulia, Emilia-Romagna, Toscana, Sicilia.

Alcuni esemplari raccolti nelle staz. 2 e 5 e presso

POsservatorio ornitologico.

Xysticus audax (Schrank)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Lombardia, Trentino- Alto Adi¬

ge, Friuli-Venezia Giulia, Emilia-Romagna, Lazio,

Campania, Calabria, Sardegna.

Alcuni esemplari raccolti nelle staz. 2 e 5.

Xysticus bifasciatus Koch

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Lombardia, Emilia-Romagna,

Basilicata, Sardegna.

Alcuni esemplari raccolti nelle staz. 2, 5 e 6.

Xysticus bufo (Dufour)

Corotipo: Mediterraneo (MED).

Presenza in Italia: Liguria, Piemonte, Lombardia,

Toscana, Lazio.

Alcuni esemplari raccolti nella staz. 2 e nell’alne-

to lungo il torrente della Val Faè.

Xysticus cristatus (Clerck)

Corotipo: Paleartico (PAL).

Presenza in Italia: Italia settentrionale, Emilia-Ro¬

magna, Toscana, Marche, Campania, Calabria, Sarde¬

gna.

Numerosissimi esemplari raccolti nelle staz. 2, 3, 5

e 6 e ad Ovest dei Piani di Barra.

Xysticus erraticus (Blackwall)

Corotipo: Europeo (EUR).

Presenza in Italia: Trentino-Alto Adige. La specie

risulta nuova per la Lombardia.

Alcuni esemplari raccolti nelle staz. 2 e 5.

Xysticus kempeleni Thorell

Corotipo: Europeo (EUR).

Presenza in Italia: Veneto, Friuli-Venezia Giulia,

Emilia-Romagna. La specie risulta nuova per la

Lombardia.

Alcuni esemplari raccolti nelle staz. 2, 3, 5 e 7.

Xysticus kochi Thorell

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutta Italia, Sardegna.

Alcuni esemplari raccolti nelle staz. 2, 3, 5, 6 e 9,

nei boschi della Val Faè e nell’alneto lungo il torren¬

te della Val Faè.

Xysticus lattio Koch

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Lombardia, Veneto, Trentino-

Alto Adige, Friuli-Venezia Giulia, Emilia-Romagna,

Toscana.

Alcuni esemplari raccolti nelle staz. 2, 5, 7, 8 e 9,

nei boschi della Val Faè, nell’alneto lungo il torrente

della Val Faè e ad Ovest dei Piani di Barra.

Xysticus ninnii Thorell

Corotipo: W.Paleartico (WPA).

Presenza in Italia: Veneto, Trentino-Alto Adige,

Friuli-Venezia Giulia, Emilia-Romagna, Toscana,

Marche, Basilicata. La specie risulta nuova per la

Lombardia.

Un 6 raccolto nella staz. 5 (28.V.1990, lg. Aureg-

gi)- |

Xysticus ulmi (Hahn)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Piemonte, Lombardia, Veneto,

Trentino- Alto Adige, Marche, Calabria.

2 6 6 e 2 9 9 raccolti nella staz. 9 (15. VI. 1990, lg.

Leonardi).

Salticidae

Aelurillus v-insignitus (Clerck)

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Italia settentrionale, Emilia-Ro¬

magna, Toscana, Basilicata, Calabria, Sardegna.

Un c3 raccolto nella staz. 5 (25. VI. 1991, lg. Aureg-

gi)-

Ballus depressus (Walckenaer)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Alcuni esemplari raccolti nelle staz. 1, 2, 5 e 6, nei

boschi della Val Faè, presso POsservatorio ornitologi-

co e ad Ovest dei Piani di Barra.

Bianor aurocinctus (Ohlert)

Corotipo: Centroasiatico-Europeo (CAE).

Presenza in Italia: Liguria, Veneto, Trentino-Alto

Adige. La specie risulta nuova per la Lombardia.

Alcuni esemplari raccolti nelle staz. 1, 2, 5 e 6 e ad

Ovest dei Piani di Barra.

I RAGNI ( ARACHNIDA ARANE AE) DEL MONTE BARRO (ITALIA, LOMBARDIA. LECCO)

259

Eris nidicolens (Walckenaer), Fig. 5

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: Liguria, Lombardia, Veneto,

Trentino-Alto-Adige, Friuli-Venezia Giulia, Emilia-

Romagna, Toscana, Marche, Umbria, Campania, Pu¬

glia, Calabria, Sardegna.

Alcuni esemplari raccolti nelle staz. 2, 4 e 5.

Heliophanus aeneus (Hahn)

Corotipo: Centroasiatico-Europeo (CAE).

Presenza in Italia: Italia settentrionale, Toscana,

Calabria, Sicilia.

Una $ raccolta nella staz. 2 (23.V.1991, lg. Leo¬

nardi).

Heliophanus auratus Koch

Corotipo: Sibirico-Europeo (SIE).

Presenza in Italia: Piemonte, Val d’Aosta, Veneto,

Trentino-Alto Adige, Friuli-Venezia Giulia, Emilia-

Romagna, Toscana, Sardegna. La specie risulta nuova

per la Lombardia.

Alcuni esemplari raccolti nelle staz. 2, 5 e presso

l’Osservatorio ornitologico.

Heliophanus cupreus (Walckenaer)

Corotipo: Europeo (EUR).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Numerosissimi esemplari raccolti in tutti gli am¬

bienti indagati eccetto la staz. 1.

Fig. 5-10 - 5) Eris nidicolens (Walckenaer), pedipalpo 6 in visione ventrale. 6) Marpissa nivoyi (Lucas), pedipalpo 6 in vi¬

sione ventrale; 7) Mithion canestrinii (Ninni), pedipalpo 6 in visione ventrale; 8) id., epigino 9 ; 9) Philaeus chrysops (Po-

da), pedipalpo ó in visione ventrale; 10) Saitis barbipes (Simon), pedipalpo 6 in visione ventrale.

260

CARLO PESARINI

Heliophanus flavipes (Hahn)

Corotipo: Asiatico-Èuropeo (ASE).

Presenza in Italia: Lombardia, Veneto, Trentino-

Alto Adige, Friuli-Venezia Giulia, Emilia-Romagna,

Toscana, Umbria, Lazio, Italia meridionale, Sicilia,

Sardegna.

Numerosi esemplari raccolti nelle staz. 2, 3, 4, 5, 6

e 9, nei boschi della Val Faè e presso rOsservatorio

ornitologico.

Heliophanus kochi Simon

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: Italia settentrionale e centrale,

Puglia, Calabria, Sardegna.

Alcuni esemplari raccolti nelle staz. 1 e 3, 4 e 5.

Marpissa nivoyi (Lucas), Fig. 6

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: Liguria, Emilia-Romagna, To¬

scana, Umbria, Lazio, Campania. La specie risulta

nuova per la Lombardia.

Una $ raccolta nella staz. 5 (15.IV.1989, lg. Leo¬

nardi).

Mithion canestrinii (Ninni), Fig. 7, 8 e 11

Corotipo: europeo (EUR).

Presenza in Italia: Veneto, Emilia-Romagna, Um¬

bria, Basilicata, Sicilia, Sardegna. La specie risulta

nuova per la Lombardia.

Numerosi esemplari (14 3 3, 11 $9 eli immatu¬

ri) raccolti nella staz. 9 (15. VI. 1990, lg. Leonardi), al¬

tri esemplari nelle stazioni 4 e 5.

Osservazioni: il genere Mithion Simon, compren¬

dente la qui presente specie come unico rappresen¬

tante, viene generalmente considerato, nella lettera¬

tura più recente, sinonimo di Marpissa. Le differen¬

ze molto nette che si riscontrano nei genitali dei due

sessi fra le varie specie di Marpissa da una lato, e la

presente specie dall’altro, mi inducono a ritenere in¬

giustificato il declassamento di Mithion , che preferi¬

sco continuare a trattare alla stregua di genere a sé

stante.

Myrmarachne formicaria (Degeer)

Corotipo: Europeo (EUR).

Presenza in Italia: Italia settentrionale e centrale,

Calabria, Sicilia, Sardegna.

Alcuni esemplari raccolti nelle staz. 2, 3, 6 e 9.

Philaeus chrysops (Poda), Fig. 9

Corotipo: Europeo-Mediterraneo (EUM).

Presenza in Italia: tutta Italia, Sicilia, Sardegna.

Un 3 raccolto nella staz. 5 (25.VI.1991, lg. Aureggi).

Saitis barbipes (Simon), Fig. 10

Corotipo: Europeo (EUR).

Presenza in Italia: Italia settentrionale e centrale,

Campania, Calabria.

Alcuni esemplari raccolti nei boschi della Val Faè

e ad Ovest dei Piani di Barra.

Salticus scenicus (Clerck)

Corotipo: Olartico (OLA).

Presenza in Italia: Italia settentrionale, Emilia-Ro¬

magna, Toscana, Umbria, Campania, Puglia, Calabria,

Sicilia, Sardegna.

Un 3 e una 9 raccolti nella staz. 6 (12. VI. 1991, lg.

Aureggi).

Fig. 11 - Mithion canestrinii (Ninni), $, habitus.

Nella seguente tabella (Tabella 1) sono riuniti i

dati relativi alla presenza delle specie nelle diverse

stazioni. Tutte le stazioni successive alla nona sono

riunite nel numero 10. Si tratta per lo più di località

situate nei boschi della Val Faè; indicazioni più detta¬

gliate, peraltro, si possono ricavare dalla precedente

trattazione delle singole specie.

Tabella 1 - Tabella riassuntiva delle specie raccolte.

I RAGNI ( ARACHNIDA ARANEAE) DEL MONTE BARRO (ITALIA, LOMBARDIA, LECCO)

261

Considerazioni conclusive

Le ricerche condotte nell’area del Monte Barro

hanno condotto al rinvenimento di 111 specie di ra¬

gni, pari al 7,89 per cento della fauna italiana com¬

plessiva; un raffronto fra la fauna censita e quella ita¬

liana è messa in evidenza nella tabella 2, dove per cia¬

scuna famiglia vengono indicati i dati sottospecifica¬

ti, relativi alla ricerca condotta sul Monte Barro (let¬

tere minuscole) e relativi all’intera fauna italiana (let¬

tere maiuscole).

262

CARLO PESARINI

Tabella 2 - Numero di specie delle singole famiglie

raccolte sul Monte Barro (a) e note per l’intero terri¬

torio italiano (A), e relative percentuali (b, B) riferite

al numero totale di specie della fauna araneologica

In ricerche condotte in aree sufficientemente di-

versificate, come è il caso dell’area del Monte Barro,

il rapporto b/B, per famiglie discretamente vaste

(comprendenti almeno una trentina di specie) è ge¬

neralmente compreso fra 0,5 e 2, con tendenza al li¬

mite inferiore per le famiglie comprendenti numero¬

se specie a distribuzione geografica ristretta ed a

quello superiore per famiglie con specie in prevalen¬

za a distribuzione ampia. Il rapporto b/B tende inol¬

tre a discostarsi più o meno nettamente dall’unità in

un senso o nell’altro (a seconda delle caratteristiche

geografiche o ecologiche dell’ambiente) nel caso di

famiglie comprendenti numerose specie stenoecie o a

distribuzione geografica marcatamente caratterizza¬

ta. Nel caso della presente ricerca, si può notare che i

limiti indicati vengono in alcuni casi largamente su¬

perati nei due sensi, per eccesso nel caso di Thomisi-

dae (3,59) e Araneidae (3,16), per difetto nel caso di

Dysderidae (0,21), Agelenidae (0,17) e Gnaphosidae

(0,09). I fattori precedentemente indicati hanno con¬

tribuito in parte al diseostamento dall’unità (Aranei¬

dae e Thomisidae comprendono numerose specie a

diffusione geografica molto ampia, mentre Dysderi¬

dae, Agelenidae e Gnaphosidae comprendono nume¬

rose specie a diffusione ristretta e/o a gravitazione

mediterranea), ma il netto superamento dei limiti

mediamente riscontrati è senz’altro da attribuirsi alle

modalità di ricerca, che hanno fornito un quadro suf¬

ficientemente completo delle specie diurne legate al¬

la vegetazione (come appunto Thomisidae ed Ara¬

neidae), mentre è pressoché sicuro che numerose

specie di Dysderidae, Agelenidae e soprattutto

Gnaphosidae (terricole e spesso a costumi notturni)

siano sfuggite alle ricerche, che in tal caso hanno for¬

nito un quadro della popolazione araneologica netta¬

mente sbilanciato a sfavore di questi ultimi taxa. No¬

nostante queste limitazioni, peraltro, i dati geonemici

ottenuti con la presente ricerca sono comunque di

notevole interesse, anche in considerazione dell’e¬

strema lacunosità delle attuali conoscenze sulla fauna

araneologica italiana: ben 5 specie risultavano infatti

non ancora segnalate per la fauna italiana, e addirit¬

tura 32 nuove per la fauna lombarda.

Indicazioni sulle caratteristiche ambientali sono

fornite dalla sottoindicata tabella corologica del po¬

polamento censito (tabella 3), che fornisce un quadro

di ambiente mesotermo, con elementi enofili in leg¬

gera maggioranza rispetto a quelli termofili e con

un’ampia componente di specie euriecie.

Tabella 3 - Spettro corologico delle specie raccolte.

Le sigle dei corotipi fondamentali sono ricavate dal

lavoro di Vigna et al. (1991).

La figura 12, dove i corotipi sono raggruppati per

categorie sintetiche, visualizza la dominanza di ele¬

menti ad ampia distribuzione (oltre il 70% delle spe¬

cie raccolte) e la totale assenza di elementi mediter¬

ranei.

I RAGNI (ARACHNIDA ARANEAE) DEL MONTE BARRO (ITALIA, LOMBARDIA, LECCO)

263

BIBLIOGRAFIA

Alicata P, 1966 - Il genere Dasumia Thorell (Araneae, Dysderi-

dae), sua nuova definizione e revisione delle specie italiane.

Meni. Mus. civ. Stor. nat., Verona, 14:465-486.

Aureggi M„ 1991 - Il popolamento araneologico del Monte Barro.

Tesi di laurea Univ. Studi Milano, corso in Scienze Biologiche.

Braun R., 1965 - Beitrag zu einer Revision der palàarktischen Ar-

ten der Philodromus aureolus- Gruppe (Arach., Araneae).

Senck. biol. , 46:369-428.

Grimm U., 1985 - Die Gnaphosidae Mitteleuropas (Arachnida,

Araneae). Abhandl. Naturwiss. Ver., Hamburg, 26:1-318.

Hànggi A., 1990 - Beitràge zur Kenntnis der Spinnenfauna des Kt.

Tessin III. Fur die Schweiz neue und bemerkenswerte Spinne

(Arachnida Araneae). Miti, scheiz ■ entom. Ges., 63:153-167.

Hansen H.. 1985 - Contributo alla conoscenza dei Salticidae ita¬

liani (Arachnida:Araneae). Boll. Mus. civ. St. nat., Venezia,

34:241-322.

Pesarini C., 1995 - Checklist delle specie della fauna italiana. 23.

Arachnida Araneae. Ed. Calderini, Bologna.

Roberts M. J., 1985 - The spiders of Great Britain and Ireland.

Voi. 1. Ed. Brill , Leiden.

Roberts M. X, 1987 - The spiders of Great Britain and Ireland.

Voi. 2. Ed. Brill , Leiden.

Simon E., 1932 - Les Arachnides de France. Ed. Mulo , Paris, 6 (4).

Simon E., 1937 - Les Arachnides de France. Ed. Mulo. Paris, 6 (5).

Tongiorgi P, 1966 - Italian wolf spiders of thè genus Pardosa

(Araneae: Lycosidae). Bull. Mus. Comp. Zool., 134:275-334.

Vigna Taglianti A., Audisio P.A., Belfiore C, Biondi M.. Bo¬

logna M.A., Carpaneto G.M., De Biase A., De Felici S..

Piattella E., Racheli T., Zapparoli M. & Zoia S., 1992 -

Riflessioni di gruppo sui corotipi fondamentali della fauna W-

paleartica ed in particolare italiana. Biogeographia , 16: 159-

179.

Wiehle H., 1956 - Die Tierwelt Deutschlands 44. Spinnentiere. 28

Familie Linyphiidae-Baldachinspinnen. ed. G. Fischer, Jena.

Wiehle H., 1960 - Die Tierwelt Deutschlands 47. Spinnentiere. XI

Micryphantidae-Zwergspinnen. ed. G. Fischer, Jena.

!

i

!

Carlo Pesarini: Museo Civico di Storia Naturale di Milano, Corso Venezia 55, 20121 Milano

Studi geobotanici ed entomofaunistici nel Parco Regionale del Monte Barro

Memorie della Società Italiana di Scienze Naturali e del Museo Civico di Storia Naturale di Milano

Volume XXVII - Fascicolo II - 1997

1

.

INDICE

Introduzione . Pag. 137

Enrico Banfi, Gabriele Galasso & Davide

Sassi - Aspetti floristico-vegetazionali del

Monte Barro (Preali di Lecco) in rela¬

zione all’area delle raccolte entomologi-

che . Pag. 139

Carlo Leonardi - Ricerca entomofaunisti-

ca nel parco regionale del Monte Barro

(Italia, Lombardia, Lecco) . Pag. 153

Paride Dioli - Gli Eterotteri (Heteropte-

ra) del Monte Barro (Italia, Lombardia,

Lecco) . Pag. 159

Carlo Pesarmi - Gli Elateridi (Coleoptera

Elateridae) del Monte Barro (Italia, Lom¬

bardia, Lecco) . Pag. 175

Carlo Pesarmi & Andrea Sabbadini - I

Cerambicidi (Coleoptera Cerambycidae)

del Monte Barro (Italia, Lombardia, Lec¬

co) . Pag. 185

Carlo Leonardi & Davide Sassi - I Criso¬

melidi (Coleoptera Chrysomelidae) del

Monte Barro (Italia, Lombardia, Lecco) ... Pag. 189

Carlo Pesarini - 1 Curculionidi in sensu la¬

to (Coleoptera Attelabidae, Apionidae e

Curculionidae) del Monte Barro (Italia,

Lombardia, Lecco) . Pag. 229

Fausto Pesarini - Gli Imenotteri Sinfidi

(Hymenoptera Megalodontidae, Cephi-

dae, Argidae, Cimbicidae, Tenthredinidae)

del Monte Barro (Italia, Lombardia, Lec¬

co) . Pag. 245

Claudio Canepari - I Coccinellidi (Co¬

leoptera Coccinellidae) del Monte Barro

(Italia, Lombardia, Lecco) . Pag. 179

Carlo Pesarini - 1 Ragni (Arachnida Ara-

neae) del Monte Barro (Italia, Lombar¬

dia, Lecco) . Pag. 251

»

-

'

■; .

Volume XIII

I - Vhnzo S., 1961- Rilevamento geologico deH’anfiteatro mo¬

renico del Garda. Parte II. Tratto orientale Garda- Adige e

anfiteatro atesino di Rivoli veronese, pp. 1-64, 25 figg., 9

tavv., 1 carta.

II - Pinna G., 1963 - Ammoniti del Lias superiore (Toarciano)

dell’Alpe Turati (Erba, Como). Generi Mercaticeras, Pseu-

domercaticeras e Brodieia. pp. 65-98, 2 figg., 4 tavv.

III - Zanzucchi G., 1963 - Le Ammoniti del Lias superiore

(Toarciano) di Entratico in Val Cavallina (Bergamasco

orientale), pp. 99-146, 2 figg. 8 tavv.

Volume XIV

I - Venzo S., 1965 - Rilevamento geologico dell’anfiteatro

morenico frontale del Garda dal Chiese all’Adige, pp. 1-82,

11 figg., 4 tavv., 1 carta.

II - Pinna G., 1966 - Ammoniti del Lias superiore (Toarciano)

dell’Alpe Turati (Erba, Como). Famiglia Dactylioceratidae.

pp. 83-136, 4 tavv.

Ili - Dieni I., Massari F. e Montanari L., 1966 - Il Paleogene

dei dintorni di Orosei (Sardegna). pp. 13-184, 5 figg., 8 tavv.

Volume XV

I - Caretto P. G., 1966 - Nuova classificazione di alcuni Brio-

zoi pliocenici, precedentemente determinati quali Idrozoi

del genere Hydractinia Van Beneden. pp. 1-88, 27 figg. 9

tavv.

II - Dieni I. e Massari F, 1966 - Il Neogene e il Quaternario

dei dintorni di Orosei (Sardegna), pp. 89-142, 8 figg., 7 tavv.

Ili - Barbieri E, Iaccarino S., Barbieri F. & Petrucci F,

1967 - Il Pliocene del Subappennino Piacentino-Parmense-

Reggiano.pp. 143-188, 20 figg., 3 tavv.

Volume XVI

I - Caretto P. G., 1967 - Studio morfologico con l’ausilio del

metodo statistico e nuova classificazione dei Gasteropodi

pliocenici attribuibili al Murex brandaris Linneo, pp. 1 -60,

1 fig., 7 tabb., 10 tavv.

II - Sacchi Vialli G. e Cantaluppi G., 1967 - 1 nuovi fossili di

Gozzano (Prealpi piemontesi), pp. 61-128, 30 figg., 8 tavv.

Ili - Pigorini B., 1967 - Aspetti sedimentologici del Mare

Adriatico, pp. 129-200, 13 figg., 4 tabb. 7 tavv.

Volume XVII

I - Pinna G., 1968 - Ammoniti del Lias superiore (Toarciano)

dell’Alpe Turati (Erba, Como). Famiglie Lytoceratidae,

Nannolytoceratidae, Hammatoceratidae (excl. Phymatoce-

ratinae) Hildoceratidae (excl. Hildoceratinae e Bouleicera-

tinae). pp. 1-70, 2 tavv. n.t.,6 figg., 6 tavv.

II - Venzo S. & Pelosio G., 1968 - Nuova fauna a Ammonoidi

dell’Anisico superiore di Lenna in Val Brembana (Berga¬

mo), pp. 71-142, 5 figg., 11 tavv.

Ili - Pelosio G., 1968 - Ammoniti del Lias superiore (Toarcia¬

no) dell’Alpe Turati (Erba, Como). Generi Hildoceras,

Phymatoceras, Paroniceras e Frechiella. Conclusioni gene¬

rali. pp. 143-204, 2 figg., 6 tavv.

Volume XVIII

I - Pinna G., 1969 - Revisione delle ammoniti figurate da Giu¬

seppe Meneghini nelle Taw. 1-22 della « Monographie des

fossiles du calcaire rouge ammonitique» (1867-1881). pp. 5-

22, 2 figg., 6 tavv.

II - Montanari L., 1969 - Aspetti geologici del Lias di Gozza¬

no (Lago d’Orta). pp. 23-92, 42 figg., 4 tavv. n.t.

Ili - Petrucci F., Bortolami G. C. & Dal Piaz G. V., 1970 - Ri¬

cerche sull’anfiteatro morenico di Rivoli-Avigliana (Prov.

Torino) e sul suo substrato cristallino, pp. 93-169, con carta

a colori al 1:40.000, 14 figg., 4 tavv. a colori e 2 b.n.

Volume XIX

I - Cantaluppi G., 1970 - Le Hildoceratidae del Lias medio

delle regioni mediterranee. Loro successione e modifica¬

zioni nel tempo. Riflessi biostratigrafici e sistematici, pp. 5-

46, con 2 tabelle nel testo.

II - Pinna G. & Levi-Setti E, 1971 - 1 Dactylioceratidae della

Provincia Mediterranea (Cephalopoda Ammonoidea). pp.

47-136, 21 figg., 12 tavv.

III - Pelosio G., 1973 - Le ammoniti del Trias medio di Askle-

pieion (Argolide, Grecia). I. Fauna del «calcare a Ptychites »

(Anisico sup.). pp. 137-168, 3 figg., 9 tavv.

Volume XX

I - Cornaggia Castiglioni O., 1971 - La cultura di Reme-

delio. Problematica ed ergologia di una facies dell’Eneoli¬

tico Padano, pp. 5-80, 2 figg., 20 tavv.

II - Petrucci F. 1972 -Il bacino del Torrente Cinghio (Prov.

Parma). Studio sulla stabilità dei versanti e conservazione

del suolo, pp. 81-127, 37 figg., 6 carte tematiche.

Ili - Ceretti E. & Poluzzi À., 1973 - Briozoi della biocalcare-

nite del Fosso di S. Spirito (Chieti, Abruzzi), pp. 129-169, 18

figg., 2 tavv.

Volume XXI

I - Pinna G., 1974 - 1 crostacei della fauna triassica di Cene in

Val Seriana (Bergamo), pp. 5-34, 16 figg., 16 tavv.

II - Poluzzi A., 1975 - 1 Briozoi Cheilostomi del Pliocene del¬

la Val d’Arda (Piacenza, Italia), pp. 35-78, 6 figg., 5 tavv.

Ili - Brambilla G., 1976 - 1 Molluschi pliocenici di Villalvernia

Alessandria). I. Lamellibranchi.pp. 79-128, 4 figg., 10 tavv.

Volume XXII

I - Cornaggia Castaglioni O. & Calegari G., 1978 - Cor¬

pus delle pintaderas preistoriche italiane. Problematica,

schede, iconografia, pp. 5-30, 6 figg., 13 tavv.

II - Pinna G., 1979 - Osteologia dello scheletro di Kritosaurus

notabilis (Lambe, 1914) del Museo Civico di Storia Natu¬

rale di Milano (Ornithischia Hadrosauridae). pp. 31-56, 3

figg., 9 tavv.

Ili - Biancotti A., 1981 - Geomorfologia dell’Alta Langa (Pie¬

monte meridionale), pp. 57-104, 28 figg., 12 tabb., 1 carta f. t.

Volume XXIII

I - Giacobini G., Calegari G. & Pinna G., 1982 - 1 resti uma¬

ni fossili della zona di Arena Po (Pavia). Descrizione e pro¬

blematica di una serie di reperti di probabile età paleoliti¬

ca, pp. 5-44, 4 figg., 16 tavv.

II - Poluzzi A., 1982 - 1 Radiolari quaternari di un ambiente

idrotermale del Mar Tirreno, pp. 45-72, 3 figg., 1 tab., 13

tavv.

Ili - Rossi E, 1984 - Ammoniti del Kimmeridgiano superiore

Berriasiano inferiore del Passo del Furio (Appennino Um¬

bro-Marchigiano), pp. 73-138, 9 figg., 2 tabb., 8 tavv.

Volume XXIV

I - Pinna G., 1984 - Osteologia di Drepanosaurus unguicauda-

tus, lepidosauro triassico del sottordine Lacertilia. pp. 7-28,

12 figg., 2 tavv.

II - Nosotti S., Pinna G., 1989 - Storia delle ricerche e degli

studi sui rettili Placodonti. Parte prima 1830-1902. pp. 29-

86, 24 figg., 12 tavv.

Volume XXV

I - Calegari G., 1989 - Le incisioni rupestri di Taouardei

(Gao, Mali). Problematica generale e repertorio iconogra¬

fico, pp. 1-14, 9 figg., 24 tavv.

II - Pinna G. & Nosotti S., 1989 - Anatomia, morfologia fun¬

zionale e paleoecologia del rettile placodonte Psephoder-

ma alpinum Meyer, 1858. pp. 15-50, 20 figg., 9 tavv.

Ili - Caldara R., 1990 - Revisione Tassonomica delle specie

paleartiche del genere Tychius Germar (Coleoptera Cur-

culionidae).pp. 51-218, 575 figg.

Volume XXVI

I - Pinna G., 1992 - Cyamodus hildegardis Peyer, 1931 (Repti-

lia, Placodontia).pp. 1-21, 23 figg.

II - Calegari G. a cura di, 1993 - L’arte e l’ambiente del Saha¬

ra preistorico: dati e interpretazioni, pp. 25-556. 647 figg.

Ili - Andri E. e Rossi E, 1993 - Genesi ed evoluzione di fran¬

genti, cinture, barriere ed atolli. Dalle stromatoliti alle co¬

munità di scogliera moderne, pp. 559-610, 49 figg., 1 tav.

Volume XXVII

I - Pinna G. & Ghiselin M. edited by, 1996 - Biology as Hi-

story. N. 1. Systematic Biology as an Historical Science, pp.

1-133, 68 figg.

Le Memorie sono disponibili presso la Segreteria della Società Italiana di Scienze Naturali,

Museo Civico di Storia Naturale, Corso Venezia 55 - 20121 Milano

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