INTRODUCTION.

CoMPARED with the work that has been done in Europe upon the Arachnida Acaridea

from the time of the classical writers, Linneus, De Geer, Hermann, and Latreille,

up to that of Dugés, Koch, Nicolet, P. Kramer, Mégnin, Michael, Neuman, Berlese,

Canestrini, Nalepa, and many others, the American literature of this group of animals

is exceedingly scanty. Thomas Say (1821), one of the first entomologists in the

United States, paid some attention to this neglected group. Later on (1836),

Dana and Whelpley, as well as Haldeman (1842), described and figured some North-

American species of Hydrachnide. In our times we meet with the well-known names

of Riley and Packard in connection with North-American Acarids of various groups,

and Mr. Harry Garman has published a paper on the Phytoptide. In 1886, Messrs.

Herbert Osborn and Lucien M. Underwood gave a “ Preliminary List of the Species

of Acarina of North America” in the ‘Canadian Entomologist.’ In Mexico, M. Alfred

Dugés has published several valuable articles on various species of Acarids inhabiting

that country, and M. Conil in Buenos Ayres has done the same for some species of the

Argentine Republic.

A certain number of American Acaridea have been described by European authors,

and some of the larger and more conspicuous species were already known to the

founders of Entomology, to Linnwus, De Geer, and Fabricius. In modern times

C. L. Koch has described several Ixodide from various parts of America, and Trouessart

and Mégnin have studied some forms of Dermaleichide which live on American birds.

‘To Antonio Berlese and R. Canestrini we are indebted for some most valuable papers

on Acaridea from the La Plata region and from Brazil.

But nevertheless we are far from possessing a knowledge of the American Acarid

fauna comparable to that which we have long had of the European forms.

In the following pages an attempt has been made to fill, to some extent, the gap

which at present separates the forms known from North America and those described by

Vi INTRODUCTION.

the above-quoted Italian authors from various parts of South America, and to charac-

terize some new types from Mexico and Central America. ‘The materials which I had

at my disposal were derived from various sources. During a stay of nearly five years

in various parts of Guatemala, I tried to make myself acquainted with the Acarid-

fauna of that country, by studying, as far as the unsettled life of a medical practitioner

would allow, the living forms. I had then with me a Hartnack microscope of but

moderate powers (objectives 4 and 7), the lenses of which became damaged by the long

influence of the excessive humidity of the climate of the Costa Grande. Moreover, I

laboured under an almost total want of modern literature on Acarids, having only some

of the works of the older writers with me. These unfavourable circumstances will

account to some extent for the differences the reader may find in the execution of the

drawings and the descriptions of some species, several of which are too delicate for

preservation in alcohol, the only method then within my reach. Many of my drawings,

especially of Gamaside, have been entirely omitted from the present memoir, as being

too incomplete to allow a comparison with the European forms; and even amongst

those which I have admitted there are some which I should have liked to revise again

from the specimens themselves.

Fortunately, this lack of preserved materials has in numerous cases been made up by

dried specimens obtained by other naturalists who have travelled in Central America.

The fact that other collectors have frequently fallen in with the same species as myself

shows that my researches, though far from complete, were sufficient at least to give an

idea of the composition of the Acarid fauna of a tropical country, and to enable me to

come to some general conclusions as to the geographical distribution cf the various

groups.

The most striking fact elicited by the study of the Acarid fauna of Central America

is undoubtedly the great similarity between the types with which we are familiar in

the temperate regions north of the European Alps and those occurring in the gloomy

shadow of the tropical forest. Under the bark and in the fissures of putrefying tree-

trunks in the tropics we meet with some minute Gamaside which only by a close

microscopical examination can be distinguished from European species living under

similar conditions. Upon various beetles of the families Copride and Passalide are

found, with others, such well-known forms as Gamasus (Holostaspis) marginatus and

G. coleoptratorum, species already described by authors of the past century. Among

the fallen leaves and in the decaying fruits of Theobroma, Lucuma, and other tropical

INTRODUCTION. Vii

trees, which lie scattered over the damp ground of the forest, we frequently observe the

slow-moving Oribatide, or the soft velvety Trombidide, the larve of which may be

found attached to the wings of dragon-flies, grasshoppers, and other insects. The

larger species of Muscide carry on their thorax the hypopial forms of Tyroglyphide,

just as they do in Kurope; and the Belostomide, which we find in the ponds of the

high valleys and barrancas of Guatemala, have their legs infested by the larve of

Hydrachnide, in the same way as are those of Kanatra and Nepa in Europe. It isa

remarkable circumstance that not one of the species described in the following

memoir represents a generic type entirely new or peculiar to Central America. With

the exception of the holotropical genus Megisthanus (fam. Gamaside), and the chiefly

American genus Amblyomma (fam. Ixodide), all the genera enumerated by me likewise

occur in the Palearctic Region.

reographical Distribution of the Genera of Acarids hitherto found in Central America.

Fam. TROMBIDID.

Gen. TromBipiuM.

Palearctic Region (Europe, N.E. Siberia).

Nearctic R. (U.S.A.).

Neotropical R. (Central and South America).

‘Ethiopian R. (Senegambia, Gold Coast, S.W. Africa, Cape of Good Hope).

Gen. RuYNCHOLOPHUS.

Palzearctic Region (Europe).

Nearctic R. (U.S.A.).

Neotropical R. (Central and South America).

Gen. Linopopes.

Palearctic Region (Europe).

Neotropical R. (Guatemala, Buenos Ayres).

Fam. ACTINEDIDZ.

Gen. ACTINEDA.

Palearctic Region (Europe, Siberia).

Neotropical R. (Central and South America).

Fam. TETRANYCHID.

Gen. TETRANYCHUS.

Palearctic Region (Europe).

Nearctic R. (U.S.A.).

Neotropical R. (Mexico, Guatemala).

Vill INTRODUCTION.

Fam. HYDRACHNID.

Gen. ATAx.

Palearctic Region (Europe).

Nearctic R. (U.S.A.).

Neotropical R. (Mexico*, Guatemala).

AKthiopian R. (East Africa +).

Gen. Nesaa (Curvipes).

Palearctic Region (Europe, Bering’s Island).

Neotropical R. (Mexico, Guatemala).

fKthiopian R.: East Africa t.

Gen. LiMNzsia.

_ Palearctic R. (Europe).

Nearctic R. (U.S.A.).

Neotropical R. (Guatemala).

fKthiopian R. (German East Africa t).

Fam. BDELLIDA.

Gen. BpELLA.

Palearctic Region (Europe, N.E. Siberia, Bering’s Island).

Nearctic R. (U.S.A.).

Neotropical R. (Guatemala, Brazil, Paraguay, La Plata).

Fam. EUPODIDA.

Gen. ScyPHius.

Palearctic Region (Europe, N.E. Siberia, Japan).

Neotropical R. (Guatemala).

Fam. IXODIDZ.

Gen. Ixopzs.

Palearctic Region (Europe, Bering’s Island).

Nearctic R. (U.S.A.).

Neotropical R. (Central and South America).

fEthiopian R. (South Africa [¢este C. L. Koch] ).

Gen. AMBLYOMMA.

Nearctic Region (U.S.A.).

Neotropical R. (Central and South America).

Oriental R. (Java, Philippine Islands, Bintang, Continental India [teste C. L. Koch ]).

* Toe Mexican species described by M. Alfred Dugis as Atax alzatei belongs, according to a private

communication of Herr F. Koenike, to the genus Nesea.

t Herr F. Koenike, the well-known specialist in this group, writes me that he possesses specimens of Ataw

collected by Dr. Stuhlmann during his expedition with Emin Pasha.

¢ According to the above-quoted communication of Herr F, Koenike.

INTRODUCTION.

Australian R. (New Holland [feste C. L. Koch]).

AMthiopian R. (South Africa [teste C. L. Koch]).

Gen. Araas.

Palearctic Region (Europe, Egypt, Persia).

Nearctic R. (U.S.A.).

Neotropical R. (Mexico, Guatemala, Paraguay).

Ethiopian R. (Ovampo Land).

Fam. ORIBATIDA.

Gen. OriBata.

Palearctic Region (Europe, N.E. Siberia, Algeria).

Nearctic R. (U.S.A.).

Neotropical R. (Central America, Brazil, Paraguay).

Gen. HoptorHora.

Palearctic Region (Europe).

Nearctic R. (U.S.A.).

Neotropical R. (Guatemala, Brazil).

Fam. NICOLETIELLIDZ.

Gen. NIcOLETIELLA.

Palearctic Region (Europe).

Neotropical R. (Guatemala).

Fam. GAMASIDA.

Gen. Uropopa.

Palearctic Region (Europe).

Nearctic R. (U.S.A.).

“Neotropical R. (Central America, Brazil, Paraguay).

Gen. HotostasPis.

Palearctic Region (Europe, Bering’s Island).

Neotropical R. (Central America, Brazil, Paraguay, La Plata).

Gen. Gamasus.

Palzearctic Region (Europe, Japan).

Nearctic R. (U.S.A.).

Neotropical R. (Central America, Brazil, Paraguay, La Plata).

Gen. CEL@NopsIS.

Palearctic Region (Europe).

Neotropical R. (British Honduras, Panama, Brazil, Paraguay, La Plata).

Gen. PacHyL#.Laps.

Palearctic Region (Europe).

Neotropical R. (Mexico, Brazil, Paraguay).

BIOL. CENTR.-AMER., Arachn, Acar., January 1893.

x INTRODUCTION.

Gen. MerGIsTHANUs.

Oriental Region (Malacca).

Australian R. (New Guinea, Queensland).

Neotropical R. (Mexico, Guatemala, Paraguay).

AKthiopian R. (Gold Coast *).

Gen. Dermanyssvs.

Palearctic Region (Europe).

Nearctic R. (U.S.A.).

Neotropical R. (Guatemala).

Fam. SARCOPTIDZ.

Gen. TyRoGLyPHUus.

Palearctic Region (Europe).

Nearctic R. (U.S.A.).

Neotropical R. (Guatemala).

Gen, Mrenin1a.

Palearctic Region (Europe).

Neotropical R. (Guatemala).

Gen. Preroticuvs.

Palearctic Region (Europe) .

Nearctic R. (U.S.A.).

Neotropical R. (Guatemala, Brazil, Guiana, Ecuador, Patagonia).

Oriental R. (Himalaya, India, Java, Philippine Islands, China).

Australian R. (New Holland, New Guinea, New Zealand, New Caledonia, Tahiti, &c.).

AAthiopian R. (Gold Coast and other parts of Africa).

Gen. ProctoPHYLLODEs.

Palearctic Region (Europe).

Neotropical R. (Guatemala).

There can be no doubt that the geographical distribution of the various families,

genera, and even species of many Acarids will eventually be found to be much larger.

Several are already known to extend over more than one of the z00-geographical

regions, 2. €.:—

Atax crassipes, O. F, Mill. t—Europe, Guatemala.

Actineda baccarum, L.t—Europe, Guatemala, Paraguay (Rio Apa), Buenos Ayres.

Holostaspis marginatus, Herm.—Europe, Guatemala, Brazil (Matto Grosso), Paraguay

(Asuncion, Rio Apa), La Plata (Buenos Ayres).

Undoubtedly the migrations of the Acarids may account, to some extent, for the

uniformity of types, especially as regards the wholly or partially parasitical species.

* I possess a new and very interesting species belonging to this remarkable genus from Accra (Gold Coast),

which I propose shortly to describe elsewhere.

T See page 47. t See page 45.

INTRODUCTION. xl

In some instances, as in the Dermaleichide, the passive migration on birds’ wings

is no doubt the usual mode of dispersion; and as the regions of Central America

form a sort of rendezvous and winter station for many birds of passage which are

infested by Dermaleichide, contact and interchange of Acarid forms of this particular

group are continually taking place. Much less extensive, though yet considerable,

is probably the passive migration and the dispersion of those Acarids which, in some

stages of their existence, adhere to insects and to bats, and which, therefore, are carried

by insects or on bats’ wings, such as various Tyroglyphide, Gamaside, Trombidide,

and Hydrachnide; the Hydracnnide attach themselves to Hemipterous water-

insects which at night abandon their ponds and take wing. In the course of many

successive generations these Acarids may thus spread over large areas. Amongst the

non-parasitic species, the active migration of those of open habits and rapid loco-

motion, such as the Trombidide, Actinedide, &c., may influence the dispersion of

types and the mutual penetration into different faunas. How far the aerial trans-

portation by wind and storm, which are such powerful agencies in the migration of

winged insects and young spiders, may facilitate the passive migration of Acarids is,

as yet, entirely unknown.

But, taken as a whole, the various modes of migration, numerous as they are,

only serve to explain the similarity of types in more or less contiguous land-areas,

such as North, Central, and South America, and the wide range of single species.

The almost universal occurrence, however, of certain genera, such as Ixodes, Argas,

Actineda, Trombidium, Rhyncholophus, Holostaspis, Oribata, Atax, and the world-

wide distribution of the fundamental types of Acarids, must have another and more

general cause. ‘This, most probably, is owing to the early dispersion of the primary

Acarid types from their centres of origin, and in the comparative persistency of

those types, due to a relatively perfect correspondence between the once acquired

differentiation of their essential organs and their modes of life. Bearing in mind the

fact that the local faunas of two so very different and widely separated regions as

Central Europe and Central America possess a comparatively large number of identical

generic types and of closely allied species of Acarids, we have perhaps a right to

generalize and to presume :—

(1) That this uniformity is, geologically speaking, very ancient, and originated

in a comparatively early geological period when the relative positions of the continents,

the islands, and the seas were altogether different from what they are now.

xil INTRODUCTION.

(2) That the Acarids long ago arrived at that degree of organic development

(progressive or regressive) which was the fittest for their various modes of life, not

partaking in the great and rapid changes of generic and specific characters which, in

the course of the more recent geological epochs, have more or less affected so many of

the higher organized types of the animal kingdom.

The presence of Megisthanus in Central America, a well-characterized Gamasid

genus which has not yet been found in any of the extratropical regions, is a fact of

peculiar interest. In his original paper Signor T. Thorell * described three species

from Java and two from New Guinea. One of the latter (1M. testudo, Thor.) has

also been mentioned by Signor G. Canestrinif as occurring in Queensland. One

species has since been added by Signor A. Berlese from Paraguay, and most

probably the “‘Gamase géant” of A. Dugés§, from Brazil, belongs to the same

genus. I have already had occasion to mention the fact that this remarkable type

also occurs in tropical Africa ||. It therefore belongs to the tropical regions of not

less than four different zoo-geographical areas, viz.: the Oriental (Java), the Australian

(New Guinea and Australia), the Neotropical (Central and South America), and the

“Ethiopian (Gold Coast)—a fact which it would be very difficult to explain by a

migratory dispersion of recent origin from one starting-point. It is far more

reasonable to regard these now so widely dispersed Megisthani as the surviving

members of a once, that is in former geological periods, coherent group of Gamasids

which have been separated in consequence of the slow but material changes of the

earth’s surface, principally by the successive breaking down of large masses of the

earth’s crust and the filling up of the thus formed gulfs by the seas.

The genus Megisthanus is by no means the only example of the occurrence of one

and the same animal type at different regions which at the present time are separated

by large tracts of sea, and which for long periods have not had any direct land

communication whatever with one another.

* T. Thorell, Descrizione di alcuni Aracnidi inferiori dell’ Arcipelago Malese, 1882.

t+ G. Canestrini, Acari nuovi o poco noti, p. 14 (Atti del R. Istituto Veneto di Scienze, Lettere ed Arti,

t. ii. ser, vi. 1884).

t A. Berlese, Acari Austro-Americani, 1888.

§ A. Dugés, Recherches sur l’ordre des Acariens, 3° Mém., 1837.

|| See above, p. x, note.

INTRODUCTION. xiil

The remarkable distribution of some of the higher animals, such as the Prosimiw

among mammals, the Ratite among birds, the Crocodilide among reptiles, is well

known, and every student of terrestrial Invertebrata who has paid some attention

to the geographical distribution of his favourite group must be acquainted with similar

facts. I may be allowed here to mention the Gasteropod genus Clausilia, the Nenia

group of which is now limited to the high valleys and mountain chains of Peru,

Ecuador, and Colombia, and, with one species only, to the island of Puerto Rico,

and which has its nearest allies not in the New, but in the Old World, in the Lami-

nifera group (Neniatlanta, Bgt.), which now lives on the top of La Rhune, a mountain

near the coast of the Bay of Biscay, and in the Garnieria group, the members of

which inhabit the mountainous districts of China, Siam, and Cambodia. On some

pieces of bark in the virgin forests of the Pacific slope of Guatemala I discovered a

new species of Diplommatina *, a Gasteropod type, the autochthonous members of

which had previously only been known from India and the neighbouring archipelagos.

In the woods near Retalhuleu (N.W. Guatemala) I found a new species of the

Myriopod genus Polyxenus, the type of which is the well-known P. lagurus, L.

Another species of this well-defined Chilognath genus has been mentioned by

Mr. Humbert from Ceylon, and one species has been described from North America

by Say. A not less characteristic Myriopod type, the genus Siphonophora, abounds

under the bark of the fir trees near the summits of the volcanos Agua and Fuego in

Guatemala, whilst a nearly allied species has been found in Madagascar by my friend,

Prof. C. Keller. Another species has been described from Ceylon by Mr. Humbert.

In the woods of the Volcan de Agua, at an elevation of about 10,000 feet, I met

with a species of land-leech belonging to the genus Cylicobdella, Grube, which is

closely allied to, if not identical with, C. lumbricoides, Gr., discovered by Prof. Fritz

Miiller at Desterro in Brazil.

Similar instances of an almost world-wide distribution might, no doubt, be found

among other groups of Invertebrata whose facilities for active or even passive

migration are very limited.

Unfortunately our present knowledge of the Acarids is too fragmentary to allow

any more definite speculations as to the phylogeny of this group. Whether

it is, geologically speaking, as ancient as some other groups of the Arachnida, or

* This species has since been described and figured as Diplommatina stolli in the ‘ Biologia Centrali-

Americana’ (Mollusca, p. 20, Tab. I. figg. 19a, 6), by Prof. E. von Martens.

XIV INTRODUCTION.

whether it is of a more recent origin, whether its various families, some of which are

not very closely allied to each other, took their origin from one or from several types,

are questions we shall probably never be able to answer. Arachnoid Arthropods

appear early in the strata of the primary periods, and it is quite possible that Acaroid

types were among them, though the delicacy and minuteness of their structure made

their preservation highly improbable. It is even possible that a closer examination

of those sedimentary layers which are fine enough for the preservation of more delicate

organisms, such as some of the tertiary strata (those of Oeningen for instance), may

lead to the discovery of the larger and more chitinized forms, such as the Ixodide,

Gamaside, and Oribatide. At present only one Acarid species is known from the

Tertiary deposits of Oeningen. A larger number of Acarid types have been described

from the Balticamber. The brown coal of Rott and the Green River beds of Wyoming

have furnished a few isolated forms.

But though, as yet, any direct proofs of the geological antiquity of the Acarid type

beyond the Oligocene are wanting, the above-quoted fact of a most extensive geogra-

phical distribution of the principal genera, and the general uniformity and similarity

of the European and extra-European local faunas, as far as they are known at present,

are highly in favour of a pretertiary origin of the Acarid types.

If we compare the Acarid fauna of those parts of Europe where it has been some-

what carefully studied with that of Central America, we are compelled to say that

Central America is comparatively poor as regards the number of species, far more

so than we should be inclined to anticipate when we take into consideration its great

variety of soil and climate and its general richness in vegetable and animal productions.

I willingly admit that the districts to which my personal researches were confined

are not very extensive, and perhaps other parts of Guatemala, such as the high valleys

of Alta Vera Paz, or the forests of the alpine mountains of the “ Altos,” or even the

richer slopes of the Atlantic coast, may have a more varied Acarid fauna; but as the

various collectors in other parts of Central America did not, in so conspicuous a

group as the Oribatide, meet with any other species than those which I obtained

in Guatemala, it seems to me probable that even those parts, when searched more

carefully, will not prove very much richer or more varied in Acarid forms, though

undoubtedly they may yield some new species which escaped my notice. I am therefore

inclined to believe that there really exists a comparative scarcity of Acarid species, at

least in Western Guatemala, and that the principal cause of this is to be found in

INTRODUCTION. XV

the atmospheric and climatic conditions of that country. For organisms of such

delicate construction, the hygrometric equilibrium of which is so easily disturbed,

the extreme aridity of the “ verano” or dry season, which in Western Guatemala lasts

for several months, must prove much more fatal than does even the European winter with

its frozen and snow-covered ground. On the other hand, the torrential ‘ aguaceros ”

of the “‘invierno” or rainy season probably cause the destruction of numerous non-

parasitic soft-bodied and unprotected Acari. It is for these reasons probably that we

find the greatest variety of species in those genera which are protected to some extent

by their entirely or partially parasitic habits, such as the Ixodide, Gamaside, Hydrach-

nide, and Dermaleichide, or which, like Trombidiwm, are capable of a somewhat rapid

locomotion, which enables them to reach, in case of need, a shelter to protect them

from being drowned or dried up. The various stages of the tough-skinned ‘“‘ Garra-

patas” (ticks) are enabled, however, to withstand alike the heat and dryness of the

‘“‘ verano” and the deluges of the “invierno.”

The limited number of species is, in some instances at least, counterbalanced to a

certain extent by an abundance of individuals. This is the case in some species

which are more resistant, or better protected against the influences of the climate, than

the majority of their congeners—for example, with Trombidium muricola, Tetrany-

chus guatemale-nove, Atax alticola, Amblyomma miatum, Orihata centro-americana,

Holostaspis marginatus, and the various species of Dermaleichide.

I regret that I had not sufficient opportunities for observing the vertical distribution

of the Central-American Acarids. My ascents of the volcanos Agua and Fuego were

both made in the dry season, in the unfavourable months of January and February,

when, at night, the temperature on the summits was as low as — 2° C., and when, from

cold and aridity, Arthropod life was reduced to a few species of Insects, Myriopods,

and Spiders, these living under the bark of the scattered fir trees and under stones *.

But, judging from what I have observed in the Swiss Alps, where I found a small

number of such conspicuous types as Rhyncholophus, Erythreus, Oribata, and Gamasus

* When I passed the night in the crater of the Volcan de Agua, 19/20 February, 1881, I found in the

morning the water in our jar covered with a crust of ice, Under the bark of a fir tree near the edge of the

crater I found the dead body of a small species of venomous snake, which had evidently been killed by the

cold. Notwithstanding, I discovered under a flat stone in the crater itself an ants’ nest, the inhabitants of

which were winged. This species has since been described by my friend, Prof. A. Forel, as Leptothorax

stolli.

XVl INTRODUCTION.

reaching the snow-line, and where one of them at least (hyncholophus nivalis, Heer)

even surpasses it*, I am inclined to believe that within the tropics Acarids will

be found at as high an elevation as any other Arthropod group.

Pror. OTTO STOLL, M.D.

Kiisnacht, near Ziirich, January 1893,

* According to the observation of the late Prof. Heer, Rhyncholophus nivalis reaches an elevation of 9580

feet (top of the Piz Levarone).

Fig.

EXPLANATION OF THE PLATES.

TAB. I.

. Trombidium mexicanum (pp. 1, 44): la, palpus; 14, mandible; 1c, first tarsus ;

1d, second tarsus.

. Trombidium trilineatum (pp. 4, 45): 2a, palpus; 2 4, tarsus; 2c, texture of the skin.

. Trombidium albicolle (pp. 5, 45): 3a, palpus.

TAB. II.

. Trombidium hispidum (pp. 2, 44): la, palpus; 16, mandible; le, first tarsus ;

1d, second tarsus.

. Trombidium guayavicola* (pp. 4, 45): 2a, palpus; 2c, tarsus.

. Trombidium muricola (pp. 5, 45): 3a, 3 4, varieties of the same.

TAB. III.

. Trombidium nasutum (pp. 2, 44): la, palpus; 16, second tarsus; le, first tarsus ;

ld, anterior margin of sternum; le, mandible; 1 f, texture of the skin; lg, skin

with hairs.

. Bdella splendida (pp. 15, 48): 2a, tarsus; 26, top of the rostrum; 2c, mandible.

. Larva of Bdella (?) sp.+ (p. 16) : 3a, first tarsus, showing the texture of the skin ;

36, mandible; 3¢, palpus; 3 d, second tarsus.

TAB. IV.

. Trombidium quinquemaculatum (pp. 8, 45).: 1a, palpus; 14, fourth joint of first leg ;

lc, first tarsus.

. Rhyncholophus erinaceus (pp. 6, 45): 2a, palpus, with top of labium; 24, section of

leg with hairs; 2c, tarsus.

* = T. muricola, var. ft Probably belongs to Rhyncholophus.

BIOL. CENTR.-AMER., Arachn. Acar., January 1893. C

XVill

Fig.

cS)

Cw)

EXPLANATION OF THE PLATES.

TAB. V.

. Actineda flaveola* (pp. 7, 45): 1a, ventral surface.

. Actineda antiguensis (pp. 7,45): 2a, palpus ; 26, mandible; 2c, tarsus (lateral view) ;

2 d, tarsus (dorsal view).

. Actineda retalteca (pp. 7, 45): 84a, tarsus (lateral view); 36, mandible; 3, tarsus

(ventral view).

TAB. VI.

. Tetranychus guatemale-nove (pp. 8, 46): la, palpi; 14, tarsus with ambulacra ;

1c, acicular mandibles.

. Scyphius maniacus (pp. 17, 48): 2a, last joint of palpus; 26, mandible; 2c, tarsus ;

2d, hypostome.

TAB. VII.

. Atax alticola (pp. 9,46) : 1 a, ventral surface ; 1 6, dorsal surface of another specimen

showing unusual position of eggs; lc, fourth joint of hind leg, showing the

swimming bristles; 1d, fourth joint of first leg; le, claws; 1f, palpus; 1g, genital

lamine.

. Limnesia guatemalteca (pp. 18, 46): 2a, ventral surface; 26, palpus; 2c, genital

lamine ; 2d, tarsus of hind leg; 2 e, top of the mandible.

. Limnesia puteorum (pp. 14, 48): 8a, palpus; 36, genital lamine; 3c, tarsus of

third leg.

TAB. VIII.

Atax septem-maculatust (pp. 9, 46, 47): 1a, ventral surface; 1 6, mandible ;

lc, palpus; 1d, genital lamine; 1e, hair of first leg.

. Limnesia leta (pp. 14, 48): 2a, part of ventral surface, showing the disposition of the

epimera and genital lamine; 20, palpus; 2¢, mandibles; 2d, tarsus of hind leg.

TAB. IX.

. Atax septem-maculatus, var. ypsilon + (pp. 10,47): la, ventral surface; 1 4, genital

lamine; 1c, palpus.

. Limnesia longipalpis (pp. 18, 47): 2a, part of the ventral surface, showing the dispo-

sition of the epimera and genital lamine; 20, mandible; 2c, palpus.

* A. flaveola, A. antiguensis, and A. retalteca = A. baccarwm, Linn., varr.

~ Probably nymphal stage of’ A. alticola.

Fig. 1.

EXPLANATION OF THE PLATES. XIX

TAB. X.

Atax dentipalpis, 2 (pp. 10, 47): 1a, ventral surface; 1 6, palpus; 1c, mandible ;

1 d, posterior margin of the abdomen, with the genital lamine (ventral view).

. Nesea guatemalensis, ¢ (pp. 11, 47): 2a, part of the ventral surface, showing the

disposition of the epimera and genital arev ; 20, palpus.

TAB. XI.

Nesea guatemalensis, $ (pp. 11, 47): la, part of the ventral surface, showing the

disposition of the epimera and genital lamine; 14, genital lamine; 1c, palpus;

1d, mandible; 1 e, section of the fourth joint of hind leg; 1/, tarsus of first leg.

Nesea numulus (pp. 12, 47) : 2a, part of the ventral surface, showing the disposition

of epimera and genital ares; 20, genital are; 2c, palpus.

TAB, XII.

Amblyomma mixtum, & (pp. 19, 49): la, the same, full of blood after suction ;

16, genital aperture; 1c, anal aperture; 1d, top of mandible (pseudochela) ;

le, stigmatic plate (peritrema); 1 f, radula of the arca maxillaris, viewed from

beneath ; 1g, tarsus of hind leg; 1/, palpus; 17, tarsus of first leg.

Amblyomma miztum, 8 (pp. 19, 49) : 2a, genital aperture; 24, anal aperture.

Amblyomma foreli, (pp. 21, 50), tarsus of hind leg: 3a, top of mandible (pseudo-

chela) ; 3, palpus of the same. (See also Tab. XIV. fig. 3.)

TAB. XIIT.

Ixodes boarum, 2? (pp. 18, 19): la, ventral surface; 1 6, dorsal surface of a young

individual; lc, sucking-apparatus, showing the palpi, the radula of the arca

maxillaris, and the mandibles (pseudochele); 1d, tarsus; le, stigmatic plate

(peritrema). (See also Tab. XIV. fig. 4.)

TAB. XIV.

Amblyomma crassipunctatum, 3 (pp. 22, 50): la, anal aperture; 1 4, genital aper-

ture; lc, stigmatic plate (peritrema) ; 1d, palpus; 1e, tarsus of first leg; 1, tarsus

of hind leg; 1g, top of the mandible ; 1 #, radula of the arca maxillaris.

. Amblyomma sabanere, 2 (pp. 23, 50): 2a, coxa of hind leg; 24, tarsus of hind

leg; 2c, tarsus of first leg ; 2d, radula of the arca maxillaris; 2, stigmatic plate

(peritrema) ; 2,f, palpus; 2g, top of the mandible; 2h, genital aperture; 27, anal

aperture.

. Amblyomma foreli, 2? (pp. 21, 50): 34, stigmatic plate (peritrema) ; 3 4, first tarsus ;

3c, genital aperture; 3d, anal aperture. (See also Tab. XII. figg. 3-3 4.)

Ixodes boarum, 2 (pp. 18, 49), anal aperture. (See Tab. XIII.)

Fig. 1.

EXPLANATION OF THE PLATES.

TAB. XV.

Oribata centro-americana (pp. 24, 50): 1a, ventral surface; 1 4, lateral view of the

cephalothorax with pteromorphe; 1c, mandible; 1d, palpus with part of the

epistomium ; le, tarsus; 1/, eggs.

. Oribata rugifrons (pp. 25, 50): 2a, ventral surface; 26, mandible; 2c, leg;

2d, palpus.

. Larva of Oribata sp. (p. 26): 8a, mandible ; 34, palpus with part of the epistomium ;

3c, tarsus; 3d, hair.

. Hoplophora retalteca (ventral view) (pp. 27, 50): 4a, lateral view; 46, mandible ;

4c, epistomium, with right palpus of the retracted mandibles ; 4d, palpus; 4e, tarsus ;

4 f, eggs.

TAB. XVI.

. Nicoletiella neotropica (pp. 27, 50): la, palpi; 16, microscopical texture of the

epiderm; 1c, mandible.

. Uropoda echinata (pp. 28, 51): 2a, hypostome and palpi; 24, tarsus; 2c, micro-

scopical texture of the epiderm; 2d, chela of the mandible ; 2 e, tarsus of first leg.

Uropoda inequipunctata (pp. 29,50): 8a, ventral view; 34, chela of the mandible ;

3c, tarsus ; 3d, anal orifice.

Celenopsis uropodoides, 2 (pp. 35, 52), ventral view: 4 a, chela of the mandible ;

4 6, tarsus of first leg; 4¢, genital orifice; 4d, microscopical texture of the skin.

(See also Tab. XIX. figg. 3-3 0.)

TAB. XVII.

. Uropoda centro-americana (pp. 30, 51): 1a, buccal parts in the ventral view, coxe

of first leg, palpi, corniculi labiales, and labium—the whole protected by the

anterior margin of the dorsal plate (the mandibles are wanting); 14, tarsus of

first leg; 1c, tarsus of second leg; 1d, chela of the mandible; le, sternal plate ;

1 f, spiraculum.

. Nymph of Uropoda centro-americana (pp. 80, 51): 2a, ventral view ; 20, tarsus.

. Uropoda piriformis (pp. 31, 51): 3a, ventral view, without the legs; 34, tarsus ;

3¢, hypostome and palpi; 3 d, chela of the mandible.

. Uropoda discus (pp. 29, 51): 4a, ventral view of the first pair of legs, palpi, and

mandibles ; 4, palpus; 4c, tarsus of second leg.

TAB. XVIII.

Megisthanus gigantodes, @ (pp. 81, 51): 1a, ventral view; 1, genital orifice ;

1c, tarsus of second leg ; 1 d, ventral view of the buccal parts.

. Megisthanus gigantodes, 8 (pp. 31, 51): 2a, ventral view; 26, chela of the mandible

(deprived of its appendages by maceration in a solution of caustic potash) ; 2 c, ventral

Fig. 1.

EXPLANATION OF THE PLATES. Xxl

view of the buccal parts; 2d, genital orifice; 2e, microscopical texture of

the epiderm; 2 f, adhesive grooves at the end of the sternal plate; 2g, chela of the

mandible with its appendages.

TAB. XIX.

Megisthanus armiger, 3 (pp. 84, 51): La, ventral view; 1 4, lip and palpi; 1c, chela

of the mandible ; 1 d, genital orifice ; 1 e, tooth-bearing joints of second leg.

. Pachylelaps heros, var. mexicanus, 3 (pp. 37, 38, 52): 2a, ventral view; 2 b, chela

of the mandible; 2c, genital orifice; 2d, ventral view of the buccal parts, lip, corni-

culi labiales, and palpi; 2e, leg of the second pair.

Celenopsis uropodoides, ¢ (pp. 35, 52), dorsal view: 3a, chela of the mandible with

its appendages ; 3 4, lip with corniculi labiales. (See also Tab. XVI. figg. 4-4.)

Celenopsis megisthanoides, 2 (pp. 36, 52) : ventral view of the buccal parts, with the

lip, corniculi labiales, and valpi.

TAB. XX.

Celenopsis megisthanoides, 9 (pp. 386, 52): la, ventral view; 16, chela of the

mandible.

Holostaspis marginatus (pp. 39, 52): 2a, ventral view ; 24, lip, corniculi labiales, and

palpi; 2c, chela of the mandible; 2 d, tarsus of second leg.

TAB. XXI.

Pterolichus momotorum, 3 (pp. 89, 52): 1a, anal appendages with the adhesive discs ;

1 4, chelze of the mandibles and palpi.

Pterolichus momotorum, 2 (pp. 39, 52): 2a, ventral view.

. Proctophyllodes sialiarum, 3 (pp. 42, 53).

Proctophyllodes sialiarum, 2? (pp. 42,53): 4a, leg of the second pair ; 4 4, chela of the

mandible; 4c, egg with embryo.

. Megninia pteroglossorum, 3 (pp. 40, 52): 5 a, nymph of ?; 5, larva.

BIOL. CENTR.-AMER., Arachn. Acar., January 1893. d

BIOLOGIA CENTRALI-AMERICANA.

ZOOLOGIA.

Class ARACHNIDA.

Order ACARIDEA.

Suborder I. ACARINA-TRACHEATA, Kramer.

Fam. TROMBIDIDA.

[Kramer, Grundziige zur Systematik der Milben, in Arch. fiir Naturg. xliii. p. 226 (1877). ]

TROMBIDIUM.

Trombidium, Latreille, Gen. Crust. et Ins. i. pp. 144, 145 (1806).

1. Trombidium mexicanum, sp. n. (Tab. I. figg. 1-1 d.)

Corpus oblongum, pyriforme, depressum, postice rotundatum, tomentoso-hirsutissimum ; tomentum e pilis

quadrifidis sistens, colore uniformi coccineo, ex sericeo nitente; superficies dorsualis impressionibus trans-

versalibus induta. Pedes breviusculi, coccineo-sericei, tomentosi; subtus (exceptis tarsis) pilis longis

pinnatis in seriem dispositis instructi. Palpi longi, marginem corporis anteriorem superantes ; pilis tomen-

tosis pinnatis induti; appendicula lobiformi lanceolata, haud lata, longe pilosa. Mandibule fusiformes,

ungue falciformi acuto armate. Oculi coccinei, in tomento fere absconditi.

Long. 5-6, lat. max. 4 millim.

Hab. Mexico, Presidio (Forrer). Two examples.

Body oblong, pyriform, depressed from above and below; shoulders protracted

between the coxe of the second and third pairs of legs; posterior part of the

body cylindrical, its hind margin rounded; dorsal surface with a few transverse im-

pressions; colour uniform, a bright scarlet; the whole body thickly covered with

velvety, quadrifid hairs. Coxe of the second and third pairs of legs separated by the

protracted shoulders. Legs rather short, when compared to the mass of the body, of

about equal length, the anterior ones a trifle thinner and longer than the others;

slightly compressed, higher than broad, thickly covered with short red hairs which give

them a whitish silky lustre; beneath bearing brushes of long, straight, pinnate hairs,

which in the fore legs are but imperfectly developed and limited to the first three

joints (counting from the coxa); the brushes are wanting from all the tarsi; front

tarsi obliquely truncate at the top, their lower surface covered with very short hairs

which are arranged into a sort of tactile brush, their claws much smaller than those

BIOL. CENTR.-AMER., Arachn. Acar., December 1886. B*

2 ACARIDEA.

of the other pairs; the tarsi of the second, third, and fourth pairs bearing long

pinnate hairs. Palpi long, extending far beyond the front margin of the body ; covered

with velvety, pinnate hairs, which on the surface of the appendicula form long fringes.

The fusiform mandibles are terminated by a broad, falciform, sharply pointed claw,

which is much shorter than the mandible itself.

The description of this beautiful species is drawn from two dried and pinned speci-

mens, which were collected by Mr. Forrer. |

2, Trombidium hispidum, sp. n. (Tab. II. figg. 1-1 d.)

Corpus ovato-trigonum, margine anteriori in apicem trigonum protracto; immaculatum, tomentoso-hirsutum,

uniformiter coccineum ; pilis rarioribus, disseminatis, elongatis, pinnatis, ex tomento exsertis indutum,

precipue in regione humerali et versus marginem posteriorem. Pedes ineequales, in paribus 1° et 4° lon-

giores ; tarsus primi paris fusiformis, unguibus minimis. Palpi exserti, pilis elongatis induti ; appendicula

pyriformi, latiuscula. Mandibule breves, ungue elongato, angusto, falciformi, subtilissime denticulato,

apice obtusulo.

Long. 2, lat. 1 millim.

Hab. Guatemata, Retalhuleu (Séol?).

Body triangular, its anterior margin protracted into a sort of triangular clypeus ;

colour uniform, scarlet. Body and legs thickly covered with a short velvety pile, out

of which spring long, disseminate, pinnate, and slightly curved hairs, which on the

shoulders and towards the end of the body are longer and more thickly set than on the

remaining parts of the dorsum. The legs are comparatively longer than in 7. mexicanum,

and without brushes on the lower surface. The front tarsus is fusiform, its claws con-

siderably smaller than in the others; the latter are truncate at their top, and bear

pinnate hairs, each of which is inserted on an elevation of the integument. The palpi

bear elongate, pinnate hairs, which on the second and third joints are arranged in a

row ; the appendicula is broader than in 7. mexicanum and bears much shorter hairs.

Mandibles short, with a rather cylindrical body, and a long, narrow, slightly curved

claw ; the concave edge of the latter is, almost imperceptibly, denticulated.

The description and figures are made from living specimens, which were found run-

ning amongst dead leaves in the cacao-plantations near Retalhuleu.

3. Trombidium nasutum, sp. n. (Tab. III. figg. 1-1 g.)

Corpus fere rhomboideum, depressulum, postice rotundatum, latitudinem maximam inter coxas secundi et

tertii pedum paris exhibens, coccineum, tomentoso-hirsutulum ; tomentum e pilis brevibus quadrifidis

constans ; pars cephalothoracis frontalis in apicem carnosum producta, clypei instar bases palporum obte-

gens; cox lateribus corporis infixe; utriusque lateris coxe anteriores inter se valde approximate,

ab coxis posterioribus (inter se approximatis) ejusdem lateris valde distantes ; dorsum impressiones plures

transversales exhibens. Primum et quartum pedum par secundo et tertio paullulum longiora; tarsus

primi paris pedum fusiformis, unguibus duobus minimis armatus. Palpi marginem clypei superantes ;

appendicula lanceolata, setas longiores pinnatas gerente. Mandibule breves, falci brevi, lata, intus

subtilissime denticulata armate.

Long. 1, lat. 0°5 millim.

Hab. Guatema.a, Retalhuleu (Séol/).

TROMBIDIUM. 3

Body rhomboidal, broadest between the coxe of the second and third pairs of legs;

scarlet, velvety ; the frontal part of the cephalothorax forming a sort of fleshy clypeus,

which covers the basis of the palpi; a few transverse furrows run across the dorsal

surface of the living animal. The coxe are inserted on the sides of the body; the first

and second pairs, which are grouped near together, widely separated from the posterior

coxe formed by the third and fourth pairs of legs. The first and fourth (?) pairs of legs

are longer than the second (?) and third, each thickly covered with short velvety hairs.

Front tarsi spindle-shaped, bearing two very small claws on the top; the other tarsi

obliquely truncate, their claws almost simple. The palpi bear long pinnate hairs, which

on the third and fourth joints are arranged into rows; the appendicula is lancet-shaped

and bears on its surface several long setaceous hairs, which, however, are rather shorter

than in 7. mexicanum. 'The mandibles are short and terminated by a short, broad,

falciform claw, the inner edge of which is denticulate.

This species is found amongst dead leaves in the forests round Retalhuleu. The

description and figures were made from the living animal.

4. Trombidium quinque-maculatum, sp. n. (Tab. IV. fige. 1-1.)

Corpus oblongo-ovoideum, depressulum, tomentosum; nigrum, maculis quinque albis dorsalibus: harum ante-

riores pares, magne, triangulares, regionem humeralem utriusque corporis lateris occupantes ; reliquee

tres macule impares, seriem formantes longitudinalem in dorso medio; ex his anterior parvula, rotunda,

in dorsi centro sita; huic proxima macula impar magna, ovalis, in abdomine medio sita; in abdominis

apice macula magna transversa impar. Apex frontalis cephalothoracis lineolam longitudinalem, brevem,

flaveolam insupra exhibens. Pedum par primum et quartum longa, crassiuscula, secundo et tertio pari

multo longiora, flavescentia, ab articulo tertio usque ad sextum nigrescentia. Palpi flavescentes, pilis

nigris sparsis induti; appendicula lata, late inserta. Mandibule?

Long. 2, lat. 0°75 millim.

Hab. GuatEMALA, near the city (Stol/).

Body oblong, a little depressed, with a longitudinal furrow on each side; velvety

from closely-set, short, thick, quadrifid hairs: colour deep black, with five white

spots; these spots are arranged as follows—two, lateral, large and triangular, occu-

pying the region between the bases of the second and third coxe; a small round

one nearly in the centre of the dorsal surface between the apices of these; a larger

ovoid one, placed between the centre and the end of the dorsal surface; and a large

transverse one on the posterior end. ‘The first and fourth pairs of legs are very long,

about the length of the body, considerably longer and stouter than the second and

third pairs; their colour is ochraceous-yellow, which from joints 3-6 merges into

blackish, owing to the short, pinnate, black hairs by which this part is clothed. Palpi

ochraceous.

I found one specimen of this richly-coloured species amongst shrubs in a ravine

near the city of Guatemala; it was running about in the bright sunshine. Unfortu-

nately, I accidentally lost the mounted preparation of the mandibles before I had drawn

and described them.

B* 2

4 ACARIDEA.

5. Trombidium guayavicola, sp.n. (Tab. II. figg. 2-2.)

Corpus oblongum, tomentosulum; nigrum, maculis duabus albis: anteriori in medio dorso sita semilunari,

impari, posteriori anali, triangulari. Oculi rubri. Pedes ochraceo-rufescentes ; par primum et quartum

secundo atque tertio longiora, crassiora ; tarsorum ungues valde recurvi, ad basin serratuli. Palporum

articuli cylindrici; appendicula brevis, recta, apice rotundata. Mandibulew ?

Long. 1, pebibus extensis 4, lat. 0°5 millim.

Hab. Guatemata, Retalhuleu (Stol/).

Body oblong; velvety-black, with two large white spots—a semilunar one on the

dorsum between the coxe of the third pair of legs, and a triangular one at the posterior

margin of the body. Eyes red; the palpi and legs of a clear reddish-brown colour.

The first and fourth pairs of legs longer and thicker than the second and third pairs ;

front tarsi spindle-shaped ; claws of the tarsi strongly curvate, with some indentations

at the basis of their concave edge. Palpi straight, slender, with almost cylindrical

joints; the fourth joint with a short claw, and a short, straight appendicula, the

latter rounded, very broadly inserted, and bearing several long hairs on the top. The

fourth pair of tarsi bear a sort of brush beneath, formed of long, oblique, slightly

pinnate hairs; these hairs do not fall off so easily as from the other tarsi, and undoubt-

edly help the animal in running up the trees.

This species is not rare in the forests near Retalhuleu, where it is to be found running

up and down the smooth trunks of the guayava trees (palo volador).

6. Trombidium trilineatum, sp. n. (Tab. I. figg. 2-2 ¢.)

Corpus oblongum, postice rotundato-truncatum, depressiusculum, coccineum, tomentosulum, hirsutie brevi,

canescenti; pseudo-prothorax albescens, sulco profundo transverso post oculos ab abdomine separatus ;

dorsum abdominis hirsutie albescenti, per sulcos duo longitudinales, laterales, parallelos, serpentes in partes

tres distinctas separatum. Pedes, palpi et mandibule rufescentes. Palpi elongati; tertio articulo

cylindrico; appendicula brevi, basi lata inserta, apice rotundata.

Long. 1:25, lat. 0°75 millim.

Hab. Guatrmaa, Antigua (Stoll).

Body oblong, with almost parallel sides; the dorsal surface divided into a pseudo-

prothorax and an abdomen by a deep transverse furrow, from which two lateral lon-

gitudinal furrows take their origin; these latter divide the back of the abdomen

into three separate, whitish aree. Legs long, slender, reddish-brown. Palpi

slender, clothed with long, stiff, dispersed hairs; their third joint long, almost

cylindrical; the appendicula short, rounded at its end, and with a few stiff hairs on the

top.

This species lives in the hedges and gardens of the valleys of Antigua and Guatemala

city. It is commonly found on the leaves of bushes, where it seems to feed on Aphides.

When the specimens, by rubbing themselves against the leaves, &c., begin to lose their

whitish velvety pile, their colour appears much redder than in the specimen figured.

TROMBIDIUM. 5

7. Trombidium albicolle, sp. n. (Tab. I. figg. 3, 3a.)

Corpus oblongum, humeris protractis, apice anali rotundato ; coccineum, hirsutulum, maculis atque striis albis

indutum ; in apice frontali pseudo-prothoracis macula alba; stria transversa lata inter humeros, postice

linguam latam medianam in abdominis dorsum emittens ; apex analis albus; duc macule albe latero-

marginales ante corporis apicem site, parve. Coxe lateribus corporis infixe. Pedes longi, graciles, rufes-

centes, inter se fere equales. Palpi graciles, pilis longis rarioribus instructi; tertio articulo elongato,

cylindrico ; quarti ungue unidentato, appendicula recta, apice rotundata, ad apicem piligera.

Long. 0°75-1 millim.

Hab. Guatemata, Antigua (Stol/).

Body oblong, rounded behind, the shoulders protruding; pseudo-prothorax trian-

gular: colour scarlet, with white spots formed by white, thickly-set, velvety hairs ;

these spots are arranged as follows—a round white one on the frontal surface

of the pseudo-prothorax, a large T-shaped one on the middle of the dorsal surface

behind the eyes, an anal one at the end of the body, and two small round lateral ones

near the margins of the posterior part of the abdomen. Legs, palpi, and mandibles of

a clear reddish colour. Legs long, slender, the first and fourth pairs a trifle longer than

the second and third. Third joint of the palpi long, cylindrical; the fourth joint with

a small tooth on the concave side of its claw, the appendicula straight, parallel-

sided, rounded at the end, where some stiff hairs are inserted.

This species is found with the preceding, on bushes in hedges and gardens in the

valley of Antigua.

8. Trombidium muricola, sp. n. (Tab. II. figg. 3-3.)

Corpus breve, obovoideum, convexum, humeris rotundatis, apice frontali rotundata; cuticula levis, sericeo-

nitida, nigra, maculis et striis albis, variantibus figura. Pedes, palpi et mandibule rufescentes. Pedes

longi, graciles ; primum par ceteris longius.

Hab. GuateMaLa, Antigua (Stoll).

Body short, ovoid, convex, with the shoulders and the frontal and anal apex

rounded ; smooth, silky-black, with white spots and stripes varying in form in the

different specimens: in some the dorsal surface of the abdomen bears a white triangular

spot on its posterior third, and from the acute angle of this, which is directed forwards,

two narrow stripes proceed obliquely towards the humeri; in others there only remains

a small white spot at the anal end, and a narrow white streak running across the

dorsum at a short distance behind the middle, the streak in its centre forming a large

angle (sometimes connected with the anal spot by a narrow white line) which opens

towards the frontal apex ; finally, there occur specimens in which the whole body is

black, except a small white border along the posterior margin. The legs are long

and slender, the front pair a little longer than the others. Legs, palpi, and man-

dibles light reddish-brown.

This species is found in the rainy season on the adobe-walls of the nopal-gardens

6 ACARIDEA.

(small plantations of Opuntia, upon which the cochineal insects are reared) round the

city of Antigua. It runs busily about in the open sunshine.

RHYNCHOLOPHUS.

Rhyncholophus, Dugés, Rech. s. Vordre d. Acar. en gén. et la fam. des Tromb. en part., Prem.

Mémoire, in Ann. des Sciences nat., Zool. i. p. 15 (1834).

1. Rhyncholophus erinaceus, sp. n. (Lab. IV. figg. 2-2 d.)

Corpus oblongum, convexum ; humeris rotundatis, paullulum prominentibus ; cuticula molli, non refulgente, ex

fusco cinerea, pilis clavatulis brevibus, quadrifidis, nigris hand sparse induta; subtus macula alba prope

anum. Palpi, mandibule atque pedes rufescentes, piligeri. Palpi articulo extremo longo, curvo ; appendi-

cula longa, lanceolata atque apice rotundata. Epimera primi et secundi pedum paris utriusque lateris in

medio corpore valde approximata, per labium fere contigua, ab epimeris posteriorum parium valde dis-

tantia ; margo corporis anterior desuper inspicienti globulum piligerum prebens.

Long. 3, lat. 1:5 millim.

Hab. Guatemata, Antigua (Stol/).

Body oblong, not depressed, with somewhat prominent shoulders, the skin not

shining, greyish-brown ; with short, black, quadrifid, thick and slightly curved hairs,

which are not very thickly set, so that the skin can be easily seen between them; the

under surface bearing a whitish spot in the anal region. The palpi, mandibles,

and legs are reddish-brown, and bear short, black, appressed, obtuse, quadrifid hairs

on their upper surface, and longer, imperceptibly pinnate, acute sete beneath. The

fourth joint of the palpi forms a curved tooth, and bears long sete like the preceding

joints and the appendicula; the latter is obtusely lanceolate in form. When looked at

from above, the anterior margin of the body appears to be prolonged into a reddish globe,

the latter bearing some long black hairs. ‘The apex of the labium forms a sort of flat

cup with many marginal fringes.

Two specimens, both of which were found under stones in the neighbourhood of

Antigua.

Fam, ACTINEDIDA.

Acaride tracheate corpore subtriangulari angulis rotundatis, brevi, minime longiore quam latiore, integro,

Oculi duo laterales, a margine corporis anteriore valde distantes, facillime perspicui. Cuticula mollis,

setis rarioribus acutis, subtilissime pinnatis, induta. Pedes laterales, articulorum senorum, epimeris

pedum in quoque latere valde approximatis. Pedes inter se fere equales longitudines, setis raris erectis

et hirsutie brevi, spissa, appressa induti. Articulus pedum tarsalis gracilescens, acute terminans, ungui-

bus duobus curvis armatus ; ad eorum basin unguis tertius spurius setulosus insertus est. Palpi quater-

norum articulorum ; articulus basalis brevis, secundus longus, quam ceteri crassior, subcylindricus, tertius

previssimus, ad apicem interne dentibus trinis, rectis, obtusis armatus, ultimus quam secundus brevior atque

angustior, apice rotundatus, setiger. Mandibule longe, ex basi lata sensim apicem versus gracilescentes,

in apice unguicula falciformi armate. Inter mandibularum bases in utroque latere corporis nascitur

organum longum tubuliforme, angustum, in apice clavatum, quod horizontaliter palpi basin transgrediens

marginem frontalem juxta palporum basin ita superat, ut a desupra inspicienti distincte et facillime

discernatur. Epistoma triangulare, acutum, apice bifido.

ACTINEDA. 7

ACTINEDA.

Actineda, Koch, Uebersicht a. Arachn. Syst. 3'* Heft, 2% Abth. p. 57 (1837).

1. Actineda flaveola, sp. n. (Tab. V. figg. 1-1 4.)

Corpus rotundo-ovoideum, supra convexulum, haud longius quam latius ; colore citreo, intestinis albide trans-

lucentibus.

Long. 0°5 millim.

Hab. Guatemata, Antigua (Stol/).

Body globose, the dorsal surface convex ; vivid yellow in colour, with some indistinct

whitish spots in the middle of the dorsum, caused by the intestinal contents shining

through the semi-transparent skin.

This species occurs on the hills round Antigua, amongst the grass.

9. Actineda antiguensis, sp. n. (Tab. V. figg. 2-2 c.)

Corpus breve, subtriangulare vel subpentagonum, paullulum depressum, minime longius quam latius ; coccineum,

maculis albidis indistinctis ex intestinis translucentibus ; in dorso sulci tres transversi breves insquidis-

tantes perspicui; corporis margines laterales antice convergentes, ante oculos angulatim flectentes ad

marginem frontalem formandum; margo posterior late truncatus, angulis rotundatis ; hirsuties alba

corporis et pedum ita ac in specie preecedenti disposita. Tarsorum unguicule stylo elongato inserte, curve,

integre, ad earum basin utrinque seta pinnata oblique inserta ; unguis tertius spurius apice in carunculam

imbutiformem dilatatus.

Long. 0°75 millim.

Hab. Guatemata, near the city, Antigua (Stoll).

Body short, obtusely pentagonal, slightly depressed from above, a little longer

than broad; carmine-red, with a few indistinct whitish spots on the dorsum; on the

latter are three short, transverse furrows, the anterior of which is situated somewhat

behind the eyes, the two hinder ones very near each other in the posterior third of

the abdomen; the anterior part from the eyes forward triangular; the front margin

rounded; the side margins not parallel, slowly diverging towards the hind one,

which is broadly truncate, with rounded angles; on the dorsum are several rows of

impinnate white shining hairs. Legs covered with short, thinly set, appressed hairs,

amongst which many long, stiff, squarrose sete are conspicuous ; the claws are inserted

on a sort of petiole, and bear on each side at their base a fringed short seta; false

claw forming a cup-like caruncle.

This species is found on shrubs in the vicinity of Antigua and the city of Guatemala ;

it has a habit of running rapidly up and down the branches of small trees.

3. Actineda retalteca, sp.n. (Tab. V. figg. 3-3 ¢.)

Corpus breve, subtrigonum, antice rotundatum, postice truncatum, angulis lateribus obtusis, paullulum depres-

sum; colore rufo, maculis dorsualibus brunneis ab intestinis translucentibus: in medio dorso inter oculos

latero-marginales macula trigona; post oculum utriusque lateris stria brunnea longa, antice bifurcata,

oblique ad marginem analem tendens. Tarsorum petiolus unguiferus nodulis tribus dorsualibus.

Long. 0°75-1 millim.

8 ACARIDEA.

Hab. GuateMata, Retalhuleu (Stol/).

Body, legs, palpi, and epistoma reddish-yellow. Body short, indistinctly triangular ;

anterior margin rounded, the posterior one truncate but with rounded angles; on the

middle of the dorsum between the eyes is a triangular brown spot, and behind each

eye another long and narrow one which goes obliquely to the poster or margin; these

three spots are caused by the intestinal contents shining through the soft and semi-

transparent skin. The petiole which bears the claws has three nodules on its back.

This species lives in the woods of the low country about Retalhuleu.

Fam. TETRANYCHIDA, Kramer.

TETRANYCHUS.

Tetranychus, Dufour, Annales des Sciences nat. xxv. p. 276 (1832).

1. Tetranychus guatemale-nove, sp.n. (Tab. VI. figg. 1-1¢.)

Corpus oblongum, antice late rotundatum, postice sensim attenuatum; humeris rotundatis, haud protractis ;

oculi latero-anteriores; cuticula mollis, semipellucida, subtilissime dense plicatula. Palpi conoidei, crassi,

trinorum articulorum. Mandibularum in unam concretarum unguicule in setas longas antice convergentes

transformate sunt, basi recurve. Tarsi unguibus duobus, inter ambulacra quatuor sitis.

Long. 0°75 millim.

Hab. GUATEMALA, near the city (Stol/).

Body oblong, its anterior margin broadly rounded; shoulders not or very little pro-

truding ; skin semi-transparent, whitish, very finely wrinkled, with some long, regularly

disposed sete amongst many short ones. Palpi short, rather thick, three-jointed, the

last joint with a sort of short double claw. The claws of the mandibles transformed

into two thin sete which converge anteriorly. Labium short, bifurcate. Tarsi with

two claws amongst four sete (‘ambulacra’ of authors), which bear on the top a

small, globose bulb.

This species lives in the vicinity of the city of Guatemala, on a common shrub of

the genus Cassia; it covers the lower surface of the leaves with its silky webs; the

yellowish, comparatively large eggs are protected under circular, transparent covers.

N.B.—I regret that I am unable to offer the reader a more exact and complete

description of this species, but I discovered it when preparing to leave Guatemala. I

had no time left then for the further study of this interesting species, and I would

not have reproduced here the above hasty notes and figures, were it not to prove the

existence of the genus Zetranychus in Guatemala.

ATAX. 9

Fam. HYDRACHNIDZ.

[C. J. Neuman, Kongl. Sv. Vet.-Ak. Handl. xvii. no. 3, pp. 16 et seqq. (1880) (Hydrachnides).]

ATAX.

Ataz (J. C. Fabricius), Neuman, Kongl. Sv. Vet.-Ak. Handl. xvii. no. 3, p. 20.

1. Atax alticola, sp.n. (Tab. VII. figg. 1-14.)

¢@. Corpus obovatum, satis altum, vix depressulum, antice et postice rotundatum, postice tuberculis duobus

setigeris prominentibus, albo-flavescens, cuticula transparente; macula dorsualis magna, nigra, margine

lobato, valde distincta, per glandulam dorsualem bicruciatam in maculas quinque desupra inspiciente

divisa ; glandula dorsualis antice brunnea, albo marginata, postice flavescens, striam latam mediam longi-

tudinalem formans, ex qua antice et postice rami bini laterales nascuntur, ita ut glandula bicruciata

appareat; rami antici latiores, postici angustiores, ramuli irregulares lobiformes emittentes. Pedes et

palpi longi, pedum par primum ceteris paullo crassius; palporum articulus extremus tridentatus. Lamine

genitales subovales, late ; stigmatibus circiter tricenis instructe.

Long. 1 millim.; lat. 0-75 millim.

Mas l\atet.

Hab. GUATEMALA, near the city (Sto//).

Body ovoid, very little depressed, transparent, whitish-yellow; the middle of the

back occupied by a large black patch which is divided by the dorsal gland into five

distinct spots; the dorsal gland forming a broad longitudinal stripe, brown with whitish

margins in its anterior half, yellowish behind; this stripe emitting two lateral branches

from its anterior third and two also from its posterior third, the anterior of which are

comparatively broad and offer several ramifications, whilst the posterior branches are

narrow and bear but a few ramifications. Legs and palpi long, slender, transparent,

light greenish. The front legs, which are only a little thicker than the rest, bear a

few pairs of long stiff spines (these spines being obliquely serrate towards the apex), and

their tarsal joint is furnished with a row of short, acute spines; the second pair has

only a few short hairs on the dorsal surface, the lower surface showing several pairs of

long spines like those of the first pair; the third pair has on the lower surface numerous

pairs of squarrose spines and a short pinnate bristle at the apical end of the fifth joint,

whilst the apex of the fourth joint bears a tuft of long swimming-hairs; the fourth

pair shows on the lower surface of the fourth, fifth, and sixth joints a row of short

broad spines, like the teeth of a comb, and the apices of the joints bear, except in the

sixth, a more prominent pinnate bristle and tufts of long swimming-hairs. The palpi

bear a few stiff spines; and the obtuse top of their fifth joint is tridentate.

This species lives in ponds in the vicinity of the city of Guatemala.

9, Atax septem-maculatus, sp.n. (Tab. VIII. figg. 1-1e.)

Corpus ovatum, convexum, pellucidum exceptis maculis dorsualibus, cum pedibus et palpis ex brunneo albes-

cens; macula dorsualis nigro-fusca, magna, per glandulam dorsualem in maculas septem disjuncta;

BIOL. CENTR.-AMER., Arachn. Acar., June 1887. c*

10 ACARIDEA.

glandula dorsualis lutea, antice lata, quadrifurcata, postice ramulos duos angustos laterales emittens. Pedum

par primum ceteris haud crassius, par ultimum ceteris longius. Lamine genitales parve, se invicem

angulis internis tangentes, obtuse pentagone ; stigmatibus majoribus quinis, minoribus binis instruct.

Long. 0°5 millim.

Hab. GuaTEMALA, near the city (Stoll).

Body ovoid, convex, transparent; brownish-white, like the legs and palpi; the dorsal

patch large, blackish-brown, separated into seven single spots by the orange-coloured

dorsal gland ; the latter divided in its anterior half into two bifurcate branches, whilst

at its posterior end it emits two small and narrow lateral branches. The first and

second pairs of legs bear on their lower surface a few pairs of long, squarrose spines,

which are indistinctly serrate at the end and inserted behind tooth-like elevations of the

epidermis; the third pair with a pinnate bristle at the apical end of the fifth joint, and

also with several swimming-hairs beneath; the fourth pair with a few short spines

beneath, the spines gradually becoming longer towards the apex of the joints, and the

apical end of the third, fourth, and fifth joints with a short, pinnate bristle, and towards

the apices of the same joints some tufts of long swimming-hairs. ‘The genital plates

are small, situated in the middle between the epimera of the fourth pair of legs

and the abdominal margin, and touch each other at their inner angles; each plate

bearing five large and two small stigmata.

Found in ponds in the vicinity of the city of Guatemala.

Var. ypsilon. (Tab. IX. figg. 1-1c.)

Corpus ovatum, pellucidum ; macula dorsuali magna nigro-fusca, granulosa; glandula dorsualis lutea, Y-formis,

integra. Lamine genitales pentagons, parvule, angulis internis se invicem tangentes, stigmatibus quinis

vel senis instructs. Pedes atque palpi sicut in typo.

Long. 0:25 millim.

Hab. GUATEMALA, near the city (Séol/).

Body ovoid, transparent, with a large brown dorsal patch, which is divided by an

orange-coloured Y-shaped dorsal gland into three distinct spots. Genital plates penta-

gonal, touching each other at their anterior angles, each bearing five or six large and

two small stigmata. Legs and palpi as in the type.

Found in the same pond with the type in the vicinity of the city of Guatemala.

I cannot consider this little Atax specifically distinct from <A. septem-maculatus,

with which it agrees in the colouring, in the shape of the legs and palpi, and in the

character and size of the genital lamine. It differs from typical A. septem-maculatus

in being a trifle smaller, and in the form of the sharply marked, non-ramified dorsal

gland.

3. Atax dentipalpis, sp.n. (Tab. X. figg. 1-1 d.)

Corpus ovatum, fere rotundum, depressulum, pellucidum, flavo-albescens, postice tuberculis duobus setigeris ;

macula dorsualis nigra, lata, per glandulam dorsualem brunneam, albo-marginatam, longam, antice bifur-

ATAX.—NESZA. 11

catam divisa. Pedes longissimi, setigeri, secundo et quarto pari ceteris longioribus. Palpi elongati, apice

tridentato, obtuso ; articulo quarto longo, cylindrico, cum dente longo valido, crasso in medio, armato.

Lamine genitales disjuncte, late, arcuate; stigmatibus senis, in binos acervos trinorum stigmatum

segregatis instructe.

Long. corp. 0°75 millim.; long. pedum 1°5 millim.

Hab. GUATEMALA, near the city (Sto//).

Body ovoid, almost globoid, a little depressed, transparent, brownish-white, with two

setigerous tubercles at its posterior end and (in the male) two small tufts of hairs at the

end of the genital fissure; dorsal patch black; dorsal gland Y-shaped, brown, with

white margins, dividing the dorsal patch into an anterior triangular, and two long,

broad, lateral spots. Legs very long and slender, the second and fourth pairs longer

than the first and third, all bearing numerous long hairs and rows of short spines.

Palpi very long; fourth joint cylindrical, bearing on the middle of its inner surface a

strong, obliquely inserted tooth which points forward; fifth joint long, slightly arcuate,

with an obtuse tridentate apex. Genital plates situated near the abdominal margin,

arcuate; each bearing six large stigmata, which are divided into two equal groups.

The epimera of the third and fourth pairs of legs form an almost quadrate plate.

Lives in stagnant ponds in the vicinity of the city of Guatemala.

NES ZEA *.

Nesea (C. L. Koch), Neuman, Kongl. Sv. Vet.-Ak. Handl. xvii. no. 3, p. 29.

1. Neswa guatemalensis, sp. n. (Tab. X. figg. 2-2 6,9; and Tab. XI.

figg. 1-1 f, 3.)

2. Corpus ovatum, convexum, pellucidum, albido-flavescens ; macula dorsuali fusco-nigrescente, per glandulam

dorsualem angustam, antice bipartitam, luteolam in quinque maculas disjuncta: tres anteriores minores,

breves, duas posteriores majores, margine exteriore arcuatas. Pedes mediocris longitudinis, a primo pari

gradatim longitudine crescentes, unguiculis valde recurvis; pedum articuli quarti atque quinti fasciculis

setarum in seriem obliquam dispositarum ad apicem instructi; pedes posteriores spinarum serie brevium

subtus armati. Palporum articulus secundus crassus, quartus dente armatus. Oculi duo magni, conici,

divergentes. Area genitalis stigmatibus numerosis, circa 18 magnis atque 8 parvis instructa, que aream

semilunarem in utroque latere fissure genitalis occupant.

Long. 0°75 millim.

3. Corpus ovatum, altum, antice obsolete truncatum ; macula dorsuali fusco-nigrescente in dorsi dimidio

posteriore sita, breviore quam in femina. Mandibule versus apicem serrulate. Pedum unguicule valde

recurve, basi incrassate inserte ; pedum quartorum articulus quartus in medio excavatus, seriebus duabus

dentium oblique oppositis in marginibus excavationis armatus. Are genitalis stigmata diffuse disposita,

circiter viginti.

Long. 0°5 millim.

Hab. Guatemata, near the city (Stol/).

@. Body ovoid, convex, whitish-yellow, transparent ; dorsal patch brownish-black ;

dorsal gland narrow, yellowish, anteriorly bifurcate, and dividing the dorsal patch into

* This genus requires a new name; it is preoccupied in Polypi (Lamouroux, 1812) and Mollusca (Risso,

1826).

o* 2

12 ACARIDEA.

five distinct spots—three short ones before, and two large, longitudinal, parallel ones

behind the lateral branches. Legs of moderate size, the first pair the shortest, the

following pairs gradually longer; all bearing tufts of swimming-hairs and spines of

varied length, and the fourth and fifth joints at their apical ends with tufts of long

swimming-hairs arranged in oblique rows; the fourth pair with a row of short spines

on its lower surface; the claws strongly curved, forming an acute angle. Palpi with

the second joint thicker than the rest, the fourth joint bearing on its middle an oblique

setigerous tooth. yes conical, diverging. Stigmata of the genital area numerous,

about twenty-six on each side, arranged on a semilunar space.

3. Body somewhat truncate at its anterior margin; dorsal patch limited to the

posterior half of the back, the anterior half milk-white. Claws strongly curved, both

of them inserted on a common swollen basis. Stigmata of the genital area numerous,

about twenty in number, not arranged in a semilunar area as in the female, but rather

irregularly disseminate on an obliquely transverse, oblong space. The fourth joint of

the hind legs bears on the middle of its inner side an excavation, the margins of which

are beset with rows of obliquely set spines or teeth placed opposite to each other. The

concave edge of the mandibles shows some very small indentations towards the apex.

The male and female above described were found in a pond in the Vicinity of

the city of Guatemala. Not having seen them in copuld, nor bred them, I am not

quite sure that they belong to one and the same species; yet from their general

appearance, their common habitat, and from the fact that I found no other Nesea,

except V. numulus, in this pond, I am inclined to think that the above-described

specimens really belong to the same species.

2. Nesea numulus, sp. n. (Tab. XI. figg. 2-2 ¢.)

Q. Corpus orbiculatum, numuli instar valde depressum, antice truncatulum, in margine anteriore utrinque

tuberculis trinis piligeris juxta oculum instructum; colore fuscescente, opacum, cuticula cribelli instar

perforatula; macula dorsualis lata, margine exteriore lobato, nigra, in dimidio anteriore maculis claris

paucis rotundis interrupta, in medio per glandulam dorsualem, latam, fuscam, postice utrinque dilatatam

divisa. Pedes breves, a primo pari gradatim longitudine crescentes, setigeri, piligeri ; par quartum serie

spinarum atque seta pinnata ad articuli quarti et quinti apicem subtus instructum ; articulus extremus

ad apicem subtus subexcavatum. Palpi marginem corporis anteriorem paullulum superantes, tenues ;

articulo quarto arcuato, dentigero. Stigmata aree genitalis numerosi, circiter triginta in quoque latere.

Oculi in margine anteriore siti.

Long. et lat. 0°75 millim.

Hab. GUaTEMALA, near the city (Stoll).

Body orbicular, very much depressed, truncate at its anterior margin, the latter

bearing three small tubercles on each side (under the microscope the skin seems

to be perforated by densely set little holes, like a sieve); colour brown; dorsal patch

black, broad, with several transparent brown spots on its anterior half, its exterior

margins lobate; dorsal gland compact, broad, brown, truncate before, laterally extended

behind. Legs short, the first pair the shortest, the following pairs gradually longer ; all

NES #A.—LIMNESIA. 13

bearing a number of spines of varied length and numerous swimming-hairs, the latter

being longest in the fourth pair; hind pair with the fourth and fifth joints bearing a

row of erect short spines (the most apical of which are pinnate) beneath, and the

lower surface of the tarsal joint slightly excavated at the apex. Stigmata numerous,

about thirty on each side, disseminate on both sides of the genital plate.

This species lives with the preceding in the vicinity of the city of Guatemala.

LIMNESIA.

Limnesia (C. L. Koch), Neuman, Kongl. Sv. Vet.-Ak. Handl. xvii. no. 3, p. 97.

1. Limnesia guatemalteca, sp.n. (Tab. VII. figg. 2-2 ¢.)

Corpus ovatum, altum, pellucidum, lete fuscescens, obscure punctulatum maculis dorsualibus quinque fuscis:

tribus anterioribus, duobus (aliquando tribus) posterioribus, glandule dorsualis albescentis ramulis divisis.

Oculi valde distantes, bini in quoque latere inter se vicini. Palpi et pedes fuscescentes. Pedum par

primum ceteris crassius, paria trina anteriora articulis extremis oblique truncatis, unguiculatis ; quarto

pare unguiculis carente, omnia sparse setigera, spinigera. Lamine genitales parve, ab epimeris posticis

trigonis distantes ; margine interiore recto se invicem tangentes, exteriore sinuato; binis stigmatibus in

utraque lamina longitudinaliter dispositis. Mandibule ungue falciformi integro. Palporum articulus

extremus apice tridentata.

Long. 0°5 millim.

Hab. Guatemata, near the city (Stol/).

Body ovoid, high, transparent, light brown, with a fine dark punctulation; dorsal

patch divided into five brown spots—three before, two behind—amongst which the

whitish dorsal gland spreads its ramifications, the limits of the latter not being so

distinct as in many other species. First pair of legs shorter and a little thicker than

the others; the tarsal joint of the three anterior pairs obliquely truncate at the apical

end. Genital plates small, placed at a little distance behind the posterior epimera, and

touching each other along the entire length of their interior margin, their side margins

slightly sinuate and diverging; each lamina bearing two large stigmata only. Man-

dibles with a falciform, narrow, non-denticulated claw.

This species lives in ponds near the city of Guatemala.

9. Limnesia longipalpis, sp. n. (Tab. IX. figg. 2-2.)

Corpus ovatum, pellucidum, altum; macula dorsuali nigra, triloba; glandula dorsuali sulphurea—antice bifur-

cata, ramis lateralibus valde distinctis, angustis, lobulatis; postice lata, minus distincta. Pedes longi-

tudinis mediocris, a primo pari gradatim longitudine crescentes; tria paria anteriora sparse setigera,

articulis tarsalibus oblique truncatis ; ultimum par subtus serie setarum natatricium longarum instructum.

Palpi valde elongati ; secundo articulo brevi, crasso, dente brevi interne instructo ; quarto articulo longissimo,

dentigero ; ultimo arcuato, obtuso, tridentato. Lamine genitales anguste, ab epimeris posticis distantes ;

margine interno se invicem tangentes ; marginibus externis divergentibus ; trinis stigmatibus, uno antico

solo, duobus posticis vicinis, instructz.

Long. 0:5 millim.

Hab. Guatemata, near the city (Stol/).

14 ACARIDEA.

Body ovoid, transparent, high, whitish-yellow, with a black, trilobate dorsal patch ;

dorsal gland sulphur-yellow—anteriorly bifurcate, and with narrow branches and sharply

marked outlines; posteriorly broad, obfuscated, and with rather indistinct outlines.

Legs of moderate size, gradually longer from the first to the fourth pairs; tarsal joint

of the first three pairs bearing several long hairs and spines, and obliquely truncate ;

the fourth and fifth joints of the hind legs with a row of long swimming-bristles

beneath. Palpi exceedingly long; the second joint rather stout, and with an erect,

short tooth; the fourth joint very long, slightly curved ; the fifth joint with an obtuse,

tridentate top. Internal edge of the falx of the mandibles very finely denticulated.

Genital plates narrow, placed at a little distance behind the hinder epimera, and

touching each other along the entire length of their interior margin; their exterior

margins diverging; three large stigmata on each lamina.

Lives in ponds in the vicinity of the capital of Guatemala.

3. Limnesia puteorum, sp.n. (Tab. VII. figg. 3-3.)

Corpus ovatum, altum, opacum, fuscum; maculis dorsualibus nigris, irregularibus ; glandula dorsualis compacta—

antice alba, longe bifurcata; postice brunnea, indistincta. Pedes mediocris longitudinis, unguiculis ante

apicem dente instructis ; antici sparse setigeri, postici (paris tertii et quarti) longis setis natatricibus

instructi. Palpi longi, articulo secundo unidentato. Mandibule falci integra. Lamine genitales oblonge,

margine interno recto, inter se valde approximate ; stigmatibus trinis magnis instructe.

Long. 1:0 millim.

Hab. GuatemMata, Antigua (Stol/).

Body ovoid, high, not transparent, brown, with irregular black spots and stripes on

its back; dorsal gland white and very distinct, bifurcate in its anterior half, brown and

indistinct behind. Legs of moderate size, the hind pair with rows of swimming-hairs ;

tarsal claws bearing a tooth on their concave edge. Palpi long, the second joint with

a tooth on its inner side. Claw of the mandibles not denticulated. Genital plates

oblong, narrow, touching each other along the entire length of the interior margin;

each bearing three large stigmata.

Lives in the “ pilas” (water-cisterns) of the city of Antigua.

4. Limnesia leta, sp.n. (Tab. VIII. figg. 2-2 d.)

Corpus ovatum, fere globatum, altum, pellucidum ; maculis nigris dorsualibus trinis in utroque latere—binis

internis magnis, singula externa parva; medio in dorso stria lata longitudinalis lutea adest, antice, postice

atque in medio transverse nigrescens. Pedes haud longi, a primo pari gradatim longitudine crescentes,

setis atque spinis variis instructi; par quartum subtus serie spinarum erectarum brevium atque setis

natatricibus longis indutum; in apice articuli tertii et quarti ejusdem paris seta pinnata adest brevis,

Palpi breves, articulus quartus dente setigero armatus obliquo. Mandibule unguiculis falciformibus,

angustis, integris. Lamine genitales in unam, polygonam, antice fissuram brevem lanceolatem preebentem

concrete ; trinis stigmatibus instructe, epimeris posticis valde approximate.

Long. 0°5 millim.

Hab. GuateMaLa, near the city (Stol/).

LIMNESIA.—BDELLA. 15

Body ovoid, almost globoid, high, transparent; yellowish-white, with six black spots

on the back, these being widely separated by a broad longitudinal yellow stripe which at

its frontal and anal end and again in its middle is itself crossed by a transverse blackish

stripe, the spots placed thus—two large ones on the anterior half of the dorsum and

two others on the posterior half, the latter separated from the former by a white

interspace, and on each side at a little distance from the anterior ones is a small

one nearer to the margin. Legs of moderate size, rather short, gradually longer

from the first to the fourth pair; all bearing many spines and swimming-bristles, which

are most numerous on the lower surface of the fourth pair; on the latter beneath

there is also a row of short, erect spines on the third, fourth, and fifth joints, together

with tufts of long swimming-hairs. Palpi rather short, their fourth joint bearing

an oblique tooth. Mandibles with a narrow, falciform, non-denticulated claw.

Genital plates united into a single large pentagonal piece, which only in its anterior half

bears a lanceolate fissure ; three large stigmata present on each side of the genital piece.

Lives in ponds in the vicinity of the city of Guatemala.

Fam. BDELLIDA.

[Kramer, Grundziige zur Systematik der Milben, in Archiv fiir Naturg. xliii. p. 244 (1877).}

BDELLA.

Bdella, Latreille, Gen. Crust. et Insect. 1. p. 153 (1806).

1. Bdella splendida, sp. n. (Tab. III. figg. 2-2 c.)

Corpus oblongum, leve ; parte antica magna, trigona, in rostrum longum acutum porrectum desinens; humeri

rotundati, post eos corpus paullo angustius, usque ad apicem analem gradatim attenuatum ; postice late

rotundatum ; colore ex fusco rubro. Rostrum ad basin paullulum inflatum, ad apicem subtus piligerum,

setule dimidio paullulum separate, divergentes. Palpiquam rostrum longiores, setis sparsis brevibus armati;

ad apicem quinti articuli valde elongati setas duas inequales ferentes, internam breviorem, externam

longiorem. Extremus palporum articulus secundo brevior, tertius atque quartus brevissimi. Mandibule

elongate, ad basin latiores, apicem versus gradatim gracilescentes, chelis minimis instructa; chelarum

dens fixus curvus, acutus; dens mobilis latus, apice truncatus. Pars antica corporis (pseudo-cephalo-

thorax), pedes et palpi coccinei; pars postica (abdomen) ex fusco rubra, stria lata rosacea at lineis tribus

transversis angustis insequidistantibus ejusdem coloris induta. Cuticula mollis, subtilissime striatula, in

dorso setas sparsas in series longitudinales dispositas gerens.

Long. 1°25 millim.

Hab. GUATEMALA, near the city (Stol/).

Body oblong, smooth, gradually narrower from the rounded shoulders towards the

anal end, the latter broadly rounded ; pseudo-cephalothorax triangular, ending in a

long, acute rostrum. The pseudo-cephalothorax, rostrum, palpi, and legs are vivid

scarlet; the rest of the dorsal surface from behind the eyes to the anus reddish-brown

with darker spots, the latter varying with and depending on the intestinal contents; a

16 ACARIDEA.

broad longitudinal stripe of a rosy light-red occupies the middle of the dorsum, and

three unequally placed transverse lines of the same colour run across the back. Palpi

longer than the rostrum; the second joint the longest, the third and fourth joints very

short; the fifth joint shorter than the second, obliquely truncate at the apical end,

where it bears two long stiff sete, the inner seta being shorter than the outer one.

Mandibles very long, broad at their base, narrowing gradually towards the end; chele

very small, their immovable tooth acute, falciform, the movable one broad, truncate at

the end. Skin soft, showing under the microscope very fine and densely-set wrinkles.

The dorsum bears several stiff setee arranged in two longitudinal rows. The point of

the epistoma has a small brush of short hairs beneath, which latter, by a narrow median

interstice, are divided into two. The hairs of the palpi and dorsum are only most finely

fringed, those on the legs being quadrifid. Claws of the tarsi broad, curved; the false

(third) claw with a short-haired brush.

This pretty Bdella lives amongst dead leaves in the hedges and gardens of the city of

Guatemala.

Note.—On the 10th of July, 1880, I found the larva of an Acarid adhering to one of

the fore legs of a large Elateroid beetle, Chalcolepidius, sp., in the woods near Retalhuleu,

and some days later a stripped-off skin of the same kind of larva on the bark of a tree.

This larva, which I have figured under the doubtful name of della, sp. (Tab. III.

fige. 3-3.d), is 0°5 millim. long, and reddish-yellow in colour, with an ovoid abdomen,

which is attenuated towards the rostrum (thus forming a sort of collum, on which

a stout rostrum is inserted); the shoulders a little prominent, rounded, and with a

large black eye-like spot on each side near the margin; the dorsal surface of the soft

abdomen beset with several transverse rows of short, quadrifid, somewhat clavate setee, and

the skin densely and finely wrinkled. The palpi four-jointed: the basal joint short, the

second thick, the third narrow, cylindrical, the fourth bearing a falciform claw and a

straight appendicula (the latter resembling that of the true Trombidia); and with a few

pinnate hairs spread over the surface, more numerous hairs adorning the appendicula.

Mandibles long, consisting of a large, broad, basal piece, which is attenuated rather

suddenly into a long, narrow branch, the latter bearing on its top an extremely small

tooth. Legs long, slender, with two curved claws and a pinnate false claw.

Prof. G. Canestrini and Prof. F. Fanzago give in their excellent treatise “ Intorno

agli Acari Italiani” (Atti Soc. Pad. v. 1877) the figure (tab. 4. fig. 1) and description

(pp. 70 et seg.) of an Acarid larva, which bears a strong resemblance to the above-

described larva from Retalhuleu, from which it differs, however, in the want of eyes

and of a false claw. The learned authors are of opinion that their larva is that of

Rhyncholophus electoralis, Koch, or of an allied form. The species from Retalhuleu

has in common with Rhyncholophus only the short quadripinnate hairs of the back and

BDELLA.—SCYPHIUS. 17

of the fourth joint of the palpi; it differs from the adult Rhyncholophi by the general

shape of the body, the insertion of the palpi, the configuration of the mandibles and

tarsi, and the finely wrinked skin.

Fam. EUPODIDZ.

(Kramer, Ueber Milben, Zeitschr. ges. Naturw. liv. p. 448 (1881).]

SCYPHIUS*.

Scyphius, C. L. Koch, Uebers. d. Arachnidensyst. Heft iii. Abth. 2, p. 62 (1837); Kramer, 1. ec.

p- 449 (1881).

1. Scyphius maniacus, sp. n. (Tab. VI. figg. 2-2 d.)

Corpus oblongum, antice acutum, postice rotundatum, supra convexulum, albidum, semipellucidum, leve, setis

raris in pedibus et abdomine indutum; humeri late rotundati, post eos abdomen coarctatum. Pedum

primum par ceteris longius, par secundum brevius. Pedes corporis margini laterali inserti. Pseudo-

cephalo-thorax triangularis, ab abdomine per sulcum transversum separatum. Oculi nulli. Palpi longi,

eorum articulus extremus penultimo longior, cylindricus, basi coarctatus, apice rotundatus, setis pluribus

rectis tactilibus armatus. Mandibule epistomium superantes, chelifers, chelarum articulus fixus curvus,

dente acuto armatus, ad basin supra setulam gerens; articulus mobilis falciformis, acutus, angustus, basi

solum atque extremo apice articulum fixum tangens. Pedum articuli extremi longi, versus apicem graci-

lescentes, unguiculis curvis, unguicula tertia spuria, recta, setulosa armati.

Long. 0°75 millim.

Hab. GvuateMaLa, Retalhuleu (Séol/).

Body oblong, rather acute towards the frontal end, rounded behind, convex, soft-

skinned, semitransparent, whitish, smooth, with a few rows of stiff, minutely pinnate

hairs on its back. Abdomen a little attenuated behind the rounded and not very

prominent shoulders. Legs inserted on the sides of the body, the first pair longer, the

second pair shorter, than the rest; epimera of pairs 1 and 2 separated by an interspace

from those of pairs 3 and 4; joints cylindrical, except the sixth, the latter gradually

attenuated towards the apical end, and bearing two curved claws and an erect brush-

like false claw. Legs and palpi with several squarrose bristles. Palpi long, their last

joint rounded at the end, and bearing several long, stiff sete. Mandibles short, but

visible from above; the fixed branch of the chele ending in a short curved tooth, which

bears a short seta of about the same length at its base outside; the movable branch

strongly curved, falciform, narrow, and touching the tooth of the immovable branch

only with its acute point; none of the branches bear any denticulations. Hyes

wanting.

This species lives in the forests of the “tierra caliente” near Retalhuleu among the

fallen leaves. It runs in a very quick but interrupted erratic manner, and is rather

difficult to capture. ‘The softness of its skin renders microscopical examination some-

what difficult.

* Preoccupied in Pisces (Risso, 1826),

BIOL. CENTR.-AMER., Arachn. Acar., Warch 1890. p*

18 ACARIDEA.

Fam. [IXODIDA.

[C. L. Koch, System. Uebers. tiber die Ordn. der Zecken, in Arch. f. Naturg. x. Jahrg. Bd. 1,

p. 220 (1844).]

IXODES.

Ixodes, C. Li. Koch, loc. cit. p. 231.

1. Ixodes boarum, sp. n. (Tab. XIII. figg. 1-le; and Tab. XIV. fig. 4, 2 .)

é latet.

2. Corpus ovatum, depressum, glabrum, in superficie dorsuali et ventrali abdominis tam sulcis longitudinalibus

quam punctis impressis instructum ; colore, animalculo vivente, ex csruleo sericeo (in animalculo alcoholo

preservato sordide ochraceo). Lamine stigmatice obtuse triangulares, stigmate excentrico, rimam

simplicem oblongam formante. Scutum occipitale latum, parvum, angulis obtusis, nitidum, punctis et

foveolis raris impressis indutum, colore castaneo uniformi. Oculi nulli. Scutum frontale parvum,

glabrum, foveis frontalibus carens, colore castaneo. Rostrum parvum, breve, colore late castaneo. Arca

mandibularis hamulis senis in utroque latere armata, quarto latissimo, quinto longissimo. Arca maxil-

laris subtus dentibus squamiformibus, rotundatis instructa. Palpi breves, rostrum longitudine haud

superantes. Pedes graciles, breves, setulis raris armati.

Long. secundum satietatem varians: 2°5 millim. in jejunis, 5 millim. in satiatis animalculis ; lat. 3°5 millim.

Hab. Guatemata, Retalhuleu (Séol/).

Male unknown. Body of the female ovoid, depressed, hairless. ‘The dorsal surface

of the abdomen shows several linear furrows, arranged in two or three concentrical

series which radiate from an imaginary centre in the occipital plate. The whole skin

of the abdomen perforated by a multitude of extremely small punctiform dimples.

Stigmatic plates very simply built, triangular, with rounded angles, the stigma forming

a simple excentrical fissure. The occipital plate is small, comparatively broad, with

obtuse angles, shining, of a uniform chestnut-brown colour, with some punctiform

dimples, principally on the sides. No eyes visible. The frontal plate small, chestnut-

brown, devoid of the two frontal grooves or fovee common to the females of Amblyomma.

Rostrum small, short. Mandibles bearing six hooks on each side, only five of which

are distinctly visible; the fourth is the broadest, the fifth the longest of all. The

maxillary teeth are scaly, rounded. The palpi are rather short; the legs comparatively

short and slender. The total length of the body varies according to the state of

digestion ; from 2°5 millim. in the empty specimens up to 5 millim. in the satiated

ones. Breadth 3°5 millim.

I found about sixty individuals of this species, all of them females, adhering to the

skin of a Boa imperator, near Retalhuleu. The rudimentary state of the genital orifice

renders it possible that the specimens are not adult.

AMBLYOMMA. 19

AMBLYOMMA.

Amblyomma, C. Li. Koch, System. Uebers. iiber die Ordn. der Zecken, in Arch. f. Naturg. x. Jahrg.

Bd. 1, p. 223 (1844).

1. Amblyomma mixtum, (Tab. XII. figg. 1-17, 9; 2-24,¢.)

Amblyomma mixtum, C. L. Koch, loc. cit. p. 227; Uebers. d. Arachnidensyst. Heft iv. pp. 74, 75,

t. 13. figg. 47 (¢), 48 (¢).

¢. Corpus ovatum, valde depressum, subtus concavum, colore ex rufo brunneo. Superficies dorsualis punctis

numerosis impressis atque lineolis arcuatis irregularibus, interruptis, undulatis, flavo-albescentibus ornata,

quee ex dorsi centro, radiorum instar, ad peripheriam corporis petunt. Earum due maxime angulum

humeralem cujusque lateris capessunt inter quas area triangularis fere unicolor et lineolis albidis fere

carens interest. Fovev frontales nulle. In abdominis parte posteriore lineole obscure fusce ex intestinis

translucentibus nate, albidis se admiscent. Inter sulculos marginis posterioris lineole albide et fusce,

breves, radiatim per pares alternantes disposite, adsunt. Scutum frontale, rostrum et palpi rufo-brunnei.

Orificium genitale rimam angustam transversalem formans. Lamina analis in utroque latere marginis

posterioris setis duabus longis armata. Pedes rufo-brunnel, setulis paucis sericeis armati.

Long. 4°5 millim.; lat. 3-5 millim.

@. Corpus ovatum, in jejunis valde depressum, in satiatis depresso-globosum. Scutum occipitale magnum,

triangulare angulis rotundatis, centrum dorsi angulo postico fere attingens, leve, colore rufo-brunneo,

marginibus lateralibus fuscis, maculis albido-flavis irregularibus, disjunctis, e margine postico in ramos

duo ramificatos discedentibus. Foveole punctiformes scuto impresse numerose, nigre. Abdomen colore

fusco-olivaceo, margine clarius brunneo, haud nitidum, setulis albidis raris ornatum, punctis, sulcis et

foveis impressis iniquum. In jejunis intestina colore fusco translucent, in satiatis abdomen colorem

uniformem obscure purpureum seu rubidum exhibet. Lamina stigmatica triangularis, angulis late rotun-

datis, lateribus arcuatis. -Rima stigmatica claviformis. Area genitalis triangularis ; orificium genitale

transversale angustum, margine anteriore subtilissime denticulato. Area analis rectangulata angulis

rotundis, valvulis analibus semilunatis ; queeque valvula in apice anteriore setis duabus, in posteriore setis

tribus armata. Scutum frontale foveis duabus rotundis ornatum. Palpi, rostrum et pedes in ambobus

sexibus equaliter constructi. Palpi rostrum haud superantes, compressi, articulo quarto brevi, in apice

tertii inserto, colore corporis, ad apicem secundi et ad basin tertii articuli macula fusca interne ornati.

Apex rostri albido-flavus. Basis rostri et anguli posteriores scuti frontalis fusci. Arca maxillaris colore

succineo, dentibus conoideis, sat erectis, inter se sat distantibus armata. Arca mandibularis in utroque

latere hamulis quinque armata: eorum primus longissimus, secundum velut appendiculam brevem

insertam ferens ; tertius, quartus et quintus in ramo segregato dispositi. Pedes rufo-brunneis, setulis

paucis armati. Pedes antici longiores, externe denticulati, ceterorum parium articulus quintus in apice

dentibus duabus armatus. Variant foemine hujus species in singulis individuis colore plus minusve

clariore scutorum occipitalis et frontalis, nec non rostri et pedum. Accedit ad hoc quod macule albide

scuti occipitalis ramificate extensione multum variant.

Long. 4°5 millim., lat. 3°5 millim. in jejunis, ad long. 12 millim. et lat. 8 millim. in satiatis.

Hab. Mexico (Koch); Guatemata, Retalhuleu, Antigua (Stoll); Nicaraeva, Chontales

(Janson); Costa Rica, Cache (Rogers).

3. Body oval, much depressed, concave on its lower surface, testaceous, the dorsal

surface with numerous punctiform black and testaceous dimples and several irregularly

shaped, arcuate, narrow whitish stripes, which radiate from the centre of the dorsum

and are sometimes interrupted so as to form a mere series of spots; a triangular area

behind the anterior margin of the collar is comparatively free from these spots. On

each side-margin and parallel to it there runs a narrow longitudinal stripe, which

p*2

20 ACARIDEA.

begins near the white eyes and ends in about the middle of the lateral margin. In the

hinder part of the body the intestines shine through the semipellucid skin in the form

of blackish spots and stripes. On the interstices between the furrows of the posterior

margin there occur alternating pairs of black and white linear stripes. The arrange-

ment of the white colouring is subject to individual variation. Colour and shape of the

frontal plate, of the rostrum, palpi, and legs, similar to that of the female, except the

two frontal dimples, which only occur in the female and are wanting in the male*.

The genital plate bears a transverse narrow fissure. ‘The anal plate bears two sete on

each side of its posterior margin.

2. Body oval, in empty specimens much depressed, in the satiated ones globose.

‘Occipital plate triangular, almost reaching the centre of the dorsum, shining, testaceous,

with dark brown side margins. From the posterior angle, which is yellowish-white,

there proceeds a ramificated branch of the same colour towards the anterior margin of

each side: these branches vary much in the different specimens; in some they are

broad and continuous, in others they are narrow and tend to resolve themselves into

several spots. The abdomen is dark brown, opaque, lighter at its margin, irregularly

dimpled and furrowed, and bears short, thinly set whitish hairs. In transparent light

under the microscope the ramifications of the intestines are visible in the form of

blackish arcuate stripes. In the specimens which are filled with blood the abdomen

assumes during life a uniform dark purple hue. The stigmatic plate in both sexes is

triangular, its fissure claviform; the stigma proper presents itself as an arcuate small

hole in a dark chitinized lamina. The genital plate is triangular, with a narrow

transverse fissure, the anterior margin of which is finely denticulated. The anal valvula

of each side shows two sete on its anterior and three on its posterior end. The front

plate bears two round dimples. The eyes are white. The palpi are compressed,

similar in colour to the body; they bear at the top of the second and the base of the

third joint a small brown spot, and are beset with several short hairs; the fourth joint,

which is very small, is inserted centrally at the top of the third one. The rostrum is

of a light transparent brown, yellowish at its extremity. The mandibles bear five hooks

arranged on two branches, the first bearing the first and second hooks, the second bearing

the third, fourth, and fifth hooks; the second hook is very short and forms a sort of

small appendage to the first one. The maxillary teeth are conoid, obliquely erect,

somewhat distant from each other, amber-yellow. The legs are light brown, whitish

at the apex of the joints; the first pair have their last joint irregularly denticulate at

its apex, and the other pairs bear two teeth at the apex of the fifth joint.

This species is the most common of all the Ixodide of Central America, and

generally known by the name of “ garrapata,” which is a corruption of “ agarrapata ”

(clasping something with the legs). I have never found the male in a parasitic state,

* They have been drawn by mistake in fig. 2 of Tab, XII.

AMBLYOMMA. 21

only free on grass and bushes in the “tierra caliente” and “ tierra fria ” of Guatemala

(Retalhuleu, Guatemala city). The female, which abounds in the woods and savanas

on grass and bushes, is occasionally rubbed off by horses, cattle, or dogs, and even by

man. It adheres tenaciously to the skin, fixing itself by perforating the cutis with its

sucking-apparatus ; and remains, when undisturbed, for several days, till filled with

blood, and then probably falls off spontaneously by its own weight. If forcibly

removed, the sucking-apparatus breaks off and remains in the wound, causing a

disagreeable and sometimes painful inflammation for a considerable time, but I never

saw any serious consequences result from it. Even in its juvenile state the garrapata

is of parasitic habits. The young, which are distinguished by the inhabitants of

Guatemala by the name of “ mostacilla” (derived from ‘‘ mostaza,” mustard), hang

to the grass in clusters of thousands, especially during the dry season; and by their

creeping on the bare skin and frequent biting they form one of the greatest plagues

to the European traveller, who is sometimes kept awake for hours during the night

by them. The males I have heard spoken of as ‘“‘conchuda.” ‘The female has been

collected by Mr. Janson in Nicaragua, by Mr. Rogers in Costa Rica, and by myself

in many places of the “tierra caliente” and “tierra fria” of Western Guatemala

(Retalhuleu, Escuintla, Antigua, Guatemala city).

Remarks. Though I have not seen the types of A. mixtum, which Koch describes

as from Mexico, I cannot doubt that the above described Amblyomma really belongs to

that species. As Koch describes and figures both sexes, his must therefore have been

a common species; and the above described is the most common of all Ixodide in

Central America, and probably also in Southern Mexico.

2. Amblyomma foreli, sp.n. (Tab. XII. figg. 3-30; and Tab. XIV. figg. 3,

3a-3 d, 2.)

3 latet.

Q. Corpus ovato-depressum, abdominis cuticula (in exemplo satiato, in alcoholo praservato) ex griseo fusca

seu olivacea, punctis, striolis transversalibus atque maculis numerosis fuscis marmorata. Scutum occi-

pitale oblonge triangulatum, angulis rotunde truncatis, planum, nitidum, punctis nigris magnis raris

impressis in superficie dorsuali ornatum, nigrum, in angulo postico maculam colore sucineo ferens, e qua

stria lata mediana obscure castanea ad marginem scuti anteriorem petens nascitur. Margo humeralis

punctis impressis caret. Scutum frontale nigrum, nitidum, punctis impressis raris ornatum ; foveole due

frontales oblonge, postice truncate, antice angulatim protracte. Arca mandibularis basi nigra, apicem

versus flavescens, hamulis quinque, binis in primo, ternis in secundo ramo dispositis armata; arca maxil-

laris colore succineo. Palpi fusci, nitidi, superficie interna deplanati, externa convexi; articulus quartus

minimus tertio excentrice insertus. Pedes ex piceo fusci, setulis paucis instructi. Lamina stigmatica

triangularis, angulis late rotundatis, rima stigmatica claviformi. Lamina analis utriusque lateris setas

duas in margine postico ferens.

Long. (in satiato) corporis 20 millim. ; rostri 1 millim., scuti occipitalis 2-5 millim.; lat. corporis 11 millim.,

scuti occipitalis 2°25 millim.

Hab. Guatemaa, Retalhuleu (Sto).

22 ACARIDEA.

Male unknown. Body of the female ovoid, the skin of the abdomen greyish-brown,

marbled with small dark spots and strie. Occipital plate triangular with rounded

angles, on its dorsal surface with black, comparatively large dimples. The general

colour of the occipital plate is shining black, with a large amber-yellow spot on its

posterior angle, which continues towards the anterior margin as a broad chestnut-brown

stripe. On the humeral margin of the scutum the punctiform dimples are wanting.

Frontal plate shining, black, with a few punctiform dimples and two oblong frontal

holes, truncate behind, angulate in front. Mandibles black at their base, becoming

yellowish towards the apex, bearing five hooks on each side, which are arranged two

and three on two branches. Palpi shining, dark brown, bearing a few short bristles,

abruptly depressed or almost concave on their inner surface, convex externally, the

fourth joint inserted excentrically on the third one. Legs dark brown, with some

bristles. Stigmatic plate triangular, with rounded angles and a claviform stigmatic

fissure. Stigma proper arcuate, with swollen margins.

I accidentally found one specimen of this species among a lot of 4. mixtum collected

at Retalhuleu. I dedicate it to my friend Prof. A. Forel, the well-known myrme-

cologist.

3. Amblyomma crassipunctatum, sp.n. (Tab. XIV. figg. 1, la-Lh, 3.)

g. Corpus ovatum, postice late rotundatum, depressum, cuticula foveolis punctiformibus sat profundis areis

levigatis irregulariter intermixtis instructa. Color obscure rubro-fuscus, maculis albidis secundum

marginem corporis distributis: macula magna rhomboidea regionem humeralem utriusque lateris occupat,

macule quatuor parve in interstitiis 3°, 5°, 7°, et 9° inter sulculos marginis postici siti sunt. In margine

laterali maculee duse vel tres adsunt. Scutum frontale supra planum, nitidum, fuscum, lateribus convexe

declivibus, sine foveis frontalibus, sulculis obliquis irregularibus nec non punctis subtilibus impressis atque

striis paucis albidis ornata. Rostrum et palpi clarius rufo-fusci. Palporum articulus quartus in tertii

apice centraliter insertus. Arca mandibularis in utroque latere hamulis tribus in duos ramos distributis.

Hamulorum apices colore succineo nitentes. Hamulus secundus primi rami bidentatus. Dentes maxillares

simplices, unicolores transparentes vitrei, dense conferti, squamiformes, modice erecti. Lamina stigmatica

parva, triangulato-semilunaris, fissura stigmatica parva, claviformi, rima stigmatis arcuata. Valvula

analis utriusque lateris setis quinque armata: tribus in margine interno, duabus in margine postico sitis.

Fissura genitalis transversa, in area polygona sita, Jabris incrassatis. Pedes rufo-fusci, ad apicem articu-

lorum albido-annulati, setulis armati.

Long. corp. 7°5 millim., scuti frontalis cum rostro 2 millim.; lat. 5 millim.

@ latet.

Hab. Nitcaracua, Chontales (Janson).

Body of the male oval, depressed, dark reddish-brown, with many deeply impressed,

punctiform dimples, between which are a few callous, smooth, irregularly distributed

spots. A comparatively large rhomboid whitish spot adorns the shoulder-region of each

side, and on the 3rd, 5th, 7th, and 9th interstices between the furrows of the posterior

margin there is a small whitish spot. A few irregular spots of the same colour are

seen on the side margin. The frontal plate is flat, shining, with some oblique furrows

and impressed dimples; a few whitish stripes interrupt the light chestnut-brown

AMBLYOMMA. 23

colour of the plate. The rostrum and palpi are light chestnut-brown ; the fourth joint

of the palpi is centrally inserted. The mandibular hooks, three in number, are of a

shining amber-yellow at the apex; the second hook of the first branch is bidentate.

The maxillary teeth are transparent, uniformly white, simple, scaly, moderately erect.

The stigmatic plate is small, its shape between triangular and obliquely semilunar ;

the stigmatic fissure short, claviform, the stigma proper small and arcuate. Tach of

the anal valvule bears five bristles. The genital fissure, which is comparatively large,

lies in a polygonal cavity and is enclosed by a sort of swollen lip. Legs reddish-

brown, whitish at the apex of the joints.

Female unknown.

The figures and description are taken from a dried specimen obtained in Nicaragua

by Mr. Janson.

4, Amblyomma sabanera, sp. n. (Tab. XIV. figg. 2, 2-27, 2.)

3 latet.

Q. Corpus ovatum, depressum. Scutum occipitale nitidum, sat dense et haud profunde punctatum, colore ex

fusco nigrescente, secundum marginem humeralem utriusque lateris macula lineari irregulari albida, que

in exemplo desiccato difficulter observatur. Scutum frontale nigro-fuscum, foveis frontalibus profundis,

ovatis, antice angulatim protractis. Abdomen haud nitens, crasse punctatum ; superficies dorsualis sulcis

longitudinalibus latis iniqua. Rostrum et palpi fusci, clariores apicem versus. Palporum articulus

quartus in tertii apice excavato centraliter insertus. Arca mandibularis hamulis quinque in ramos duos

dispositis: hamulus secundus primi rami bidentatus, hamulus primus secundi rami brevissimus. Dentes

maxillares acuti, sat dense conferti, in medio apicem versus torulo succineo incrassati. Lamina stigmatica

triangularis, angulis rotundatis, fissura stigmatica irregulariter claviformis, lata; rima stigmatis irregu-

lariter arcuata. Valvula analis utriusque lateris setis quinque armata. Apertura genitalis margine

posteriore recto, laterali flexuose convexo; inter rugulas integumenti parietis anterioris aperture genitalis

toruli lineares recti observantur. Pedes clarius fusco-rufi, coxe dentibus duobus respicientibus armati.

Long. corp. 7 millim. ; scuti occipitalis 2 millim. ; lat. corp. 5 millim.

Hab. Guatemata, Retalhuleu (Sto//).

Male unknown. Body of the female oval, depressed. Occipital plate shining,

punctate, brownish-black, with an irregular whitish stripe on the shoulder-margin,

which almost disappears after desiccation. Frontal plate brownish, the two frontal

holes deep and oblong. Abdomen not shining, rather coarsely punctate, with some

broad longitudinal furrows on its upper surface. Rostrum and palpi brown, lighter

towards the apex; the fourth joint of the palpi centrally inserted on the third one,

which has its apex excavated. Five mandibular hooks arranged on two branches; the

second hook of the first branch bidentate, the first one of the second branch very short

and rudimentary. Maxillary teeth acute, with an amber-yellow longitudinal swelling on

the middle, their margin double-bordered. The stigmatic plate is triangular with

rounded angles; the stigmatic fissure irregularly claviform, comparatively broad, the

stigma proper moderately arcuate. ach anal valvula bears five bristles. The posterior

margin of the genital orifice is straight, transverse, its side margin convex, arcuate; a

24 ACARIDEA.

series of short linear swellings between the ripples of the integument of the anterior

margin. Legs light brown. ‘The coxe bear two broad, rounded teeth.

I found two females of this species attached to the throat and tail of a small terrapin,

known to the natives by the name of “la Sabanera.” The figures and description are

taken from specimens preserved in alcohol.

Fam. ORIBATIDE.

[Dugés, Rech. sur Pordre des Acar., 3° Mém., in Ann. Sci. Nat. sér. 2, 1. p. 21, Oribatet (1834) ;

Kramer, Grundziige zur System. der Milben, in Arch. f. Naturg. xliii. p. 215 (1877).]

Subfam. PTEROGASTERINA.

[Michael, British Oribatide, pp. 64 & 202 (1834).]

ORIBATA.

Oribate, Latreille, Hist. nat. gén. et partic. des Crust. et des Ins. vii. p. 400 (1804); Gen.

Crust. et Ins. i. p. 148 (1806).

1. Oribata centro-americana, sp.n. (Tab. XV. figg. 1, 1a-1f)

Corpus globosum, supra valde convexum, nigrum, leve, nitidum, sine sculptura microscopica ulla. Dorso-vertex

ab abdomine non separatus, antice sulco transverso ab rostri tecto separatum. Rostrum tectum, valde

declivum, triangulare, antice late angulatum, simplex. Lamelle breves, anguste, apice brevi, acuto, seta

mediocris longitudinis armate. Pseudostigmata ab desupra inspicienti non perspiciuntur. Organa

pseudo-stigmatica longa, setiformia, apice paullulum incrassato. Tectopsdia non conspicua. Pedes rufo-

fusci, mediocris longitudinis, setulis armati, coxis, femoribus atque tibiis posticis complanatis ; tarsus

unguibus tribus instructus. Pteromorphe modice, antice protracte, late rotundate, plerumque corpori

appresse, ita ut a desupra inspicienti difficulter videantur, colore rufo-fusco, semi-pellucide. Lamine

genitales ab analibus valde distantes, iis minores, aream rotundato-pentagonam occupantes. Lamine

anales semilunares. Palpi nihil extraordinarii exhibent. Mandibule crasse, breves, brachia chelarum

dentibus quatuor obtusis armata. Maxille incisuram longitudinalem margini externo vicinam profundam

prebent, que partem anteriorem marginis externi dentis instar discernit.

Long. corp. 0°9 millim.; lat. corp. 0°8 millim.

Hab. British Honpuras, R. Hondo, R. Sarstoon, Belize (Blancaneaur) ; GUATEMALA,

Antigua, Guatemala city (StolZ); Panama, Volcan de Chiriqui 2500 to 4000 feet

(Champion).

Body globose, of a short and almost circular shape, broad and rounded behind ;

colour black, the legs and edges of the pteromorphe brown ; texture polished, shining ;

without any hairs or minute sculpture on the dorsal surface. Cephalothorax compara-_

tively broad ; rostrum simple, broadly pointed ; lamellz small and narrow, short, ending

in a short acute point; from the anterior margin of the lamelle there project two

comparatively short bristles on each side. Tectopedia wanting. Pseudostigmata

short, difficult to be seen from above, projecting from the angle between the basis of

ORIBATA. 25

the cephalothorax and the anterior insertion of the pteromorphe. Pseudostigmatic

organs moderately large, slightly increasing in size towards the ends, a little recurved

on the notogaster. No interlamellar hairs conspicuous. . Coxe and femora of the two

posterior pairs of legs rather flattened. Notogaster not separated from the dorso-

vertex, entirely hairless. Pteromorphe middle-sized, flexible, semi-transparent, and

light-coloured ; projecting obliquely forward, and having rounded anterior ends, when

seen from the side (from the dorsal aspect their anterior ends seem rather pointed).

Genital plates widely separated from the anal plates, occupying a sort of pentagonal

area, whilst the anal area is rather circular. Mandibles bearing four blunt teeth on

each branch of the chele. Anterior margin of the maxilla showing a deep longitudinal

fissure near the outer edge.

This species seems to be common and widely distributed throughout Central America.

I have found specimens of it in Antigua and in Guatemala city, under stones and on the

moist walls of the house-wells (pilas). It has also been collected in British Honduras

by M. Blancaneaux, and on the Volcan de Chiriqui by Mr. Champion. One of tke

dried specimens from British Honduras which I dissected contained about twenty oval

eggs, of 0°3 millim. length.

2. Oribata rugifrons, sp.n. (Tab. XV. figg. 2, 2a-2d.)

Corpus ovoideum, supra convexiusculum, antice attenuatum, postice late rotundatum, nigrum, nitidum, nudum,

supra sculptura microscopica e rugulis longitudinalibus subtilissimis confecta ornatum, que in cephalo-

thorace magis conspicus, in notogastro paullulum obsolete sunt. Cephalothorax ab abdomine sulculo

transversali discretus, valde declivus, conicus, antice late angulatus, simplex. Rostri clypeus a dorso-

vertice non discretum. Lamelle haud conspicue. Pseudostigmata recondita ; organa pseudo-stigmatica

mediocria, in animalculo desiccato setiformia, apice incrassato. Sete interlamellares absunt. Tectopzedia

haud conspicua. Pedes mediocres, colore fusco, setulis et unguibus tribus armati. Pteromorphe longa,

sat anguste, antice angulatim protracte, rotundate, postice acutiuscule, mobiles: corpori appresse pedes

omnes obtegunt. Abdominis latera ad recipiendas pteromorphas leviter excavata. Sculptura microscopica

pteromorphorarum e rugulis radiatim ex insertione sese fundentibus confecta, Lamine anales semilunares,

genitalibus majores. Laminz genitales ab analibus valde distantes, aream rotundato-pentagonam occu-

pant. Mandibule crasse, chelarum brachium fixum dentibus 4, brachium mobile dentibus 5 armatum.

Palporum articulus secundus incrassatus, quintus in medio dentem unguiformem acutum, curvum gerens.

Long. corp. 0°85 millim. ; lat. max. 0-6 millim.

Hab. British Honpuras, Belize (Blancaneaux); GuatEMALa, Retalhuleu (Séol/).

Body ovoid, convex, rounded behind, its anterior end somewhat blunt; black, shining,

but not polished, without hairs on its dorsal surface, this latter showing a minute sculp-

ture consisting of closely placed, extremely fine, longitudinal wrinkles, which are more

distinct on the cephalothorax than on the notogaster. A transverse furrow separates

the notogaster from the cephalothorax, which is very simply built, conical, ending in a

somewhat blunt point. Hood of the rostrum forming but one piece with the cephalo-

thorax. Lamelle wanting. » Pseudostigmata apparently hidden, invisible from above ;

pseudostigmatic organs in the dried specimens of moderate size, setiform, increasing

BIOL. CENTR.-AMER., Arachn. Acar., September 1891. E*

26 ACARIDEA.

towards the end, slightly recurved on the notogaster. Interlamellar hairs and tecto-

pedia apparently wanting. Legs brown, bearing three claws and some bristles.

Pteromorphe long, rather narrow, slightly coloured, brown, semitransparent, their

anterior end protracted forward so as to nearly reach the top of the rostrum, rounded,

the posterior end somewhat pointed; they are very flexible, and when closed com-

pletely hide the legs, the whole body then assuming the shape of a small black seed.

The minute texture of the pteromorphe consists of extremely fine wrinkles, which

radiate from their point of insertion. The sides of the anterior part of the abdomen

are slightly excavated for the reception of the pteromorphe. Anal plates larger than

the genital plates, occupying a somewhat pentagonal area. Genital plates semilunar.

Mandibles short, thick; the fixed branch bears four, the flexible branch five, short

blunt teeth. Second joint of the palpi thick; the fifth joint bearing on its middle a

claw-like, pointed, slightly curved tooth.

Examples of this species were captured by me in the forests near Retalhuleu, where

it lives on dead wood in damp places during the rainy season, in company with Hoplo-

phora retalteca.

Note.—0O. rugifrons being the only true Oribata observed by myself in the “tierra

caliente” of Retalhuleu, it seems possible that the nymphal form of this genus

delineated by me on Tab. XV., figg. 3, 3a-d, belongs to this species. Clusters of

hundreds of individuals of these were found crawling on the underside of a piece of

dead wood in a cacao-plantation near Retalhuleu on the 3rd of July, 1880. They bear

a marked resemblance to those nymphal forms upon which Koch founded his genus

Murcia, especially to his M. trimaculata (C. L. Koch, Deutschl. Crust., Myr. und Ins.

Heft ii. p. 136. n. 21).

The following are the notes which I then made on the living animal :—

Body oblong, arched, broadly rounded behind, rather diminishing in size towards the

somewhat blunt anterior end. Cephalothorax distinctly separated from the notogaster

by a deep furrow, attenuated at its base, conical, large, triangular ; palpi projecting on

the sides of the apex when seen from above. General colour greyish-white, the dark

intestines shining through the smooth and transparent skin. In the angles of the

abdomen on each side a globose, yellow, shining corpuscle. The dorsal surface bearing

a few long pinnate bristles. On the legs the hairs more numerous, also pinnate, but

shorter. First pair of legs the longest, the first and fourth pairs longer than the

second and third. Tarsi with one claw only. Mandibles short, large, the fixed

branch with four, the flexible branch with three teeth. Maxille of each side bearing

four differently-sized teeth. The pseudostigmata looking like black eye-like spots.

Two long bristles projecting on each side in front of the pseudostigmata. Long.

0-5 millim. |

HOPLOPHORA.—NICOLETIELLA. 27

Subfam. APTEROGASTERINA.

[Michael, British Oribatide, i. p. 64 (1884).]

HOPLOPHORA.

[C. L. Koch, Uebers. d. Arachnidensyst. Heft iii. p. 116 (1842).]

1. Hoplophora retalteca, sp.n. (Tab. XV. figg. 4, 4 a-4f')

Corpus ovatum, convexum, nitidum, glabrum, colore clarius rufo-fusco. Cephalothorax conicus, declivus,

mobilis, antice rotundato-acutus. Notogastri latera post cephalothoracem late excisa. Mandibuli crass,

dentibus quatuor in quoque brachio armate. Dens secundus in brachio fixo extra seriem insertus.

Maxillarum margo anterior incisuris minus profundis in dentes tres latos divisus. Pedes breves, tarsus

unguibus duobus validis, tertio angustiore armatus.

Long. corp. 1 millim.

Hab. Guatemaa, Retalhuleu (Stol/).

Body ovoid, arched, shining, without any hairs on its dorsal surface, reddish-brown.

Cephalothorax conical, broadly angular towards its anterior ends, the side margins

somewhat rounded. Sides of the notogaster behind the cephalothorax slightly exca-

vated. Mandibles large, with four teeth on each branch of the chele; second tooth

out of the row on the blade of the chela. Two longitudinal short fissures divide the

maxilla into three broad teeth. Legs short; tarsus bearing three claws, two of which

are stronger than the other.

Found during the rainy season on dead wood in damp places in the forests near

Retalhuleu.

Note.—I reproduce the drawing and description of the tarsus, as I made them when

in Retalhuleu. But still I do not feel quite sure about the correctness of what I saw

eleven years ago, as the tarsus of the European Hoplophora nitens bears only one

claw. Having no preserved specimens of H. retalteca at my disposal at the present

time I cannot decide the question.

Fam. NICOLETIELLIDZ.

NICOLETIELLA.

Nicoletia, G. Canestrini & F. Fanzago, Intorno agli Acari Italiani, p. 52 (1877).

Nicoletiella, R. Canestrini, Osserv. sulla Nicoletiella cornuta, p. 6 (1882).

1. Nicoletiella neotropica, sp.n. (Lab. XVI. figg. 1, 1 a-1¢.)

Corpus oblongo-ovatum, convexum, antice attenuatum, margine anteriore bicornuto, colore sanguineo. Super-

ficies dorsualis setis sparsis induta. Dorsi cuticula foveolis microscopicis rotundis vel hexagonis, que inter-

stitiis transverse striolatis separate: sunt, regulariter et dense punctulata. Pedes antici ceteris longiores

atque crassiores, ceteri graciles ; pedes postici secundis atque tertiis paullulum longiores. Tarsi primi

E* 2

28 ACARIDEA.

et secundi paris unguibus duobus, tertii et quarti paris unguibus tribus armati. Tubercula lateralia valde

conspicua, oblonga. Mandibule chelate, crasse, in margine externo sub insertione brachii fixi chelarum

dentibus sex brevibus regularibus ornate. Chelarum brachium fixum curvum, acutum, dente valido ante

apicem armatum; brachium valde curvum, in medio serrulatum.

Long. corp. 0°5 millim.

Hab. Guatemata, Retalhuleu (Stol/).

Body oblong, convex above, slightly diminishing in size towards the anterior margin,

which bears two acute cornicles; blood-red, the legs and cornicles slightly coloured ;

a few short bristles on the dorsal surface, which shows a minute texture consisting of

thickly-set round or hexagonal grooves, separated by transversely striated interstices ;

on each side between the second and third pairs of legs there projects an oblong

tubercle. Anterior pair of legs longer and thicker than the others, which are rather

slender ; hind legs a little longer than the second and third pairs. The tarsi of the

two anterior pairs of legs bearing two, those of the third and fourth pairs three claws.

Mandibles short, thick; the fixed branch of the chele slightly curved, pointed, bearing

a strong tooth near its apical end; the movable branch strongly curved, its inner edge

serrulate from the middle to the base ; under the base of the fixed branch the body of

the mandible shows a row of six short regular teeth.

Found on one occasion only among fallen leaves in a forest near Retalhuleu.

Fam. GAMASIDA.

[P. Mégnin, Monogr. de la famille des Gamasides, in Journ. de l’anat. et de la

physiologie (1876).]

Subfam. UROPODIN.

UROPODA.

Uropoda, Latreille, Gen. Crust. et Ins, i. pp. 157, 158 (1806).

1. Uropoda echinata, sp. n. (Tab. XVI. figg. 2, 2 a-2e.)

Corpus supra et infra convexulum, subglobulare, paullulum longius quam latius, dorsi scutum ovale, corneum,

colore brunneo, ab corporis margine membrana albido-grisea late separatum, punctulis densis microscopicis

nec non setis brevibus indutum. In membrana conjunctiva marginali series tres conulorum microscopium

ostendit, in quorum quoque seta brevis, spiniformis adest. Tarsus pedum paris primi unguibus caret ;

ceterorum parium ungues graciles, acuti. Palpi simplices, breves, crassi. Mandibule longe protractiles,

graciles, chelis angustis, parvis. Chelarum brachium fixum mobili sat longius, ad apicem dilatatum, ambo

brachia dentibus obtusis indistinctis armata. Scutum ventrale convexulum, foveolis punctatum.

Long. 0°75 millim.

Hab. Guatemaa, Antigua (Stoll).

Body almost globular, a little longer than broad; the dorsal and ventral plates chiti-

UROPODA. 29

nous, reddish-brown, widely and completely separated by a whitish membrane, the latter

bearing several rows of small conical protrusions, on each of which is a short thorn-like

bristle; the dorsal plate also shows several short bristles and a dense microscopical

punctuation. The legs are slender, comparatively long; the tarsi of the first pair

are without claws, the remaining tarsi with two slender claws. Palpi short, 5-jointed,

simple, rather thick. Mandibles, when protracted, long and slender; the fixed

branch of the chele is longer than the movable one, both branches being indistinctly

and bluntly denticulated. Ventral plate rather convex, dotted with small grooves.

One specimen, found crawling among mould under a hedge in the vicinity of Antigua,

Guatemala.

2. Uropoda inzequipunctata, sp.n. (Tab. XVI. figg. 3, 3 a-3 d.)

Corpus valde depressum, oblonge ovatum, antice in apicem brevem protractum, postice late rotundatum, nitidum,

colore coccineo. Dorsum microscopio inspicienti foveolas punctiformes sparsas ostendit, inter quas puncta

minora numerosa, marginem versus sese accumulantia sita sunt. Pedes breves, longitudine fere equales,

tarsi primi paris unguibus carentes. Mandibule longer, graciles; chele graciles, parve, earum brachia

irregulariter atque subtiliter denticulata.

Long. 0°5 millim.

Hab. Guatemata, Retalhuleu (Stol0).

Body flat, oblong, its anterior border forming a short acute angle, its posterior border

broadly rounded, shining, scarlet-red; the dorsal surface shows several punctiform

grooves and the space between them is very finely punctured by numerous microscopic

points, which are more numerous near the borders. Legs short, almost equal in length ;

anterior tarsi without claws, the tarsi of the remaining legs with some thorn-like spines.

Mandibles long and slender, with small chele, the branches of which are irregularly

denticulated.

Found at Retalhuleu as a parasite on a coprophagous beetle (Pinotus sp.) called

‘‘yonron ” by the inhabitants.

3. Uropoda discus, sp.n. (Tab. XVII. figg. 4, 4-4.)

Corpus planum, fere orbiculare, antice leviter protractum, brunneum, nitidum. Palpi breves, in animalculo

sese moventi marginem anteriorem paullulum superantes, eorum articulus quartus tertio longior, ad apicem

setis nec non areis verrucosis, granulatis, circumscriptis nonnullis ornatus. Pedum per primum breve,

antenniforme, unguibus carens, ejus articulus secundus atque tertius dentibus obtusis brevibus irregulariter

serratis, articulus ultimus setulis numerosis armatus. Mandibule longe, tenere, translucide albide ; chelis

corneo-flavis, parvis, subtiliter denticulatis.

Long. 0°3 millim.

Hab. Guatemata, Retalhuleu (Stoll).

Body flat, almost orbicular, its anterior margin slightly protracted, but round.

Colour of the body, palpi, and legs brownish-red, shining ; mandibles white, transparent,

their chele yellowish. Palpi rather short, their last joint showing several granulated

30 ACARIDEA.

spots and some bristles. Mandibles long and slender, the branches of the chele apparently

deeply denticulated. Anterior pair of legs rather short, without claws, their second and

third joints irregularly denticulated ; the posterior pair of legs longer than the others.

I found one example of this species in a decayed chichique-fruit in the woods near

Retalhuleu in June 1880. It is nearly allied to the European U. cassidea, Herm.

4. Uropoda centro-americana, sp.n. (Tab. XVII. figg. 1, la-1f; 2, 2a,

2 6, nymph.)

Qyuv. Corpus depressum, oblongo-ovoideum, antice inter secundum et tertium pedum par oblique subtrunca-

tum, ita ut pars anterior scuti dorsualis in angulum obtusum protrahatur. Superticies dorsualis plana,

marginem versus declivis, foveolis numerosis cribrata, ex quibus setule breves enascuntur, colore brunneo

claro (in desiccato animalculo), minus nitente. Pedes omnes unguiferi, sat breves. Articulus ultimus

primi paris pedum setis numerosis ornatis, inter quas una longissima juxta ungues sita, ungues in manu-

brio longo gracili inserti, graciles. Articulus ultimus ceterorum parium pedum setulis sparsis atque

spinis duabus juxta ungium pediculum armatus, brevis. Palpi breves, setigeri, in articulo penultimo

seta longa, bifida. Palpi maxillares bidentati. Sub apice anteriore scuti dorsualis setule dus in-

serte. Mandibule graciles, chelarum brachia fere longitudine squales, dentibus paucis et obtusis in

margine interno undulata.

Long. 1 millim.; lat. 0-6 millim.

Hab. Nicaracua, Chontales (Janson). -

Body (of the young female) depressed, oblong, its anterior margin forming a somewhat

obtuse angle; dorsal surface even, marked with numerous grooves, out of each of which

a short bristle arises; the colour, in dry specimens, a clear reddish-brown, not very

shining. Legs rather short, all of them bearing claws: on the tarsi of the first pair

the claws are fixed on a sort of slender petiole and surrounded by numerous long hairs,

one of which is very much longer than the others; the tarsi of the second, third, and

fourth pairs bear short bristles and two incrassated spines at the base of the petiolus of

the claws. Palpi short, bearing numerous long bristles on their last joint; on the

inner side of their third joint there is a long, projecting, pinnate hair. Mandibles

slender, their chele small, blunt at the top, bearing on the inner edges of the brachia

four or five obtuse teeth.

(N.B.—Adhering to the posterior abdominal segments of a Guatemalan specimen of the

Coleopterous genus Atractocerus I found numerous nymphs of a Uropoda (figg. 2, 2a, 26)

which I am inclined to identify with the above-described U. centro-americana, as they

have most of the characters in common, except some which may be the result of the

differences of the respective stages of development. These differences are as follows :—

Body flat, oblong, not so distinctly angular on its anterior margin, yellowish, trans-

parent, the hairs on the dorsal plate apparently a little longer and less numerous; the

incrassated spines of the legs (which in the adult are placed at the base of the claw)

attached to the side of the tarsus, one of them on the false joint and the other on the

tarsus proper. Length 0-4, breadth 0:25 millim.

Clusters of these nymphal forms attach themselves by viscous threads to the skin of

UROPODA.—MEGISTHANUS. 31

their host, the threads being strong enough to keep them from falling off, even when

dried up or preserved in spirit.

5. Uropoda piriformis, sp.n. (Tab. XVII. figg. 3-3 d.) |

Corpus ovato-piriforme, subconvexum, antice et postice rotundatum, obscure brunneum (in exsiccato), pilis

brevibus paucis in margine ornatum. Cuticula foveolis numerosis cribrata. Palpi simplices, setigeri, in

articulo basali seta crassa armati. Mandibularum chele dentibus numerosis in brachiis ambobus armate.

Orificium genitale subtrapezoideum.

Long. 1:2 millim.; lat. max. 0°9 millim.

Hab. Mexico, Jalapa (Hége).

Body longer than broad, somewhat piriform, a little convex on the back, naked,

except for a few short scattered hairs on the margin; dorsal and ventral plates rather

coarsely punctured. Palpi simple; one strong bristle on the inner side of the basal

joint. Anterior margin of the epistome lobed; two strong bristles on the ventral

surface of the exterior lobes.

One specimen.

Subfam. GAMASINAE.

MEGISTHANUS.

Megisthanus, T. Thorell, Descriz. di alc. Aracnidi inferiori dell’ Arcipel. Malese, in Ann. Mus.

Genova, xviii. p. 48 (1882).

1. Megisthanus gigantodes, sp.n. (Tab. XVIII. figg. 1-1d, 2; 2-29, ¢.)

3. Corpus longius quam latius, inverse subovatum, antice attenuatum, ita ut subpiriforme appareat, supra

modice convexum, nitidum, nudum exceptis pilis paucis sparsis ad marginem cephalothoracis anteriorem

in utroque latere sitis, suberectis, nec non setis longis sex vel septem in utroque latere marginis poste-

rioris in seriem oblique dispositis, equidistantibus. Color ferrugineo-fuscus, in nonnullis obscurior,

in aliis, praecipue in junioribus, clarior. Scutum dorsuale in lateribus et postice limbo albido angusto

cinctum; texturam microscopicam e areolis polygonis confectam prebet, inter quas foveole rariores

impress sunt. Latitudo maxima post medium corporis invenitur. Margo integer, subcompressus,

postice late rotundatus, antice truncatus. Venter (in desiccatis et in alcoholo preservatis) in medio

convexus, ad latera declivis, levis; ejus limbus angustissimus, albicans. Scutum sternale angustum, sat

longum, leve, ad maximam partem ex rufo albicans, margine anteriore truncato, posteriore rotundato,

lateribus ob coxarum insertionem sinuatis. In ejus parte anteriore inter coxas secundi paris pedum

orificium genitale parvum, circulare situm est; ad marginem posteriorem in utroque latere foveam vallo

albido lato circumdatam vides, ex qua spinula fortis nascitur. Scutum anale a sternali interstitio albido

angustissimo separatum, obscure ferrugineo-fuscum, margine anteriore excavato, ita ut marginem poste-

riorem scuti sternalis recipiat, marginibus lateralibus disgredientibus, rotundatis, margine posteriore

corporis apicem analem attingens; orificium anale parvum, oblonge ovatum, inter scuti medium atque

marginem posticum situm. Pars anterior et latera scuti sternalis nec non scutum anale et scuta lateralia

texturam microscopicam e sulculis anastomosantibus confectam prebent. Scutum laterale utriusque

lateris integrum, postice post coxas quarti pedum paris in angulum prope marginem situm apice rotun-

datum desinens, a scuto anali interstitio albido, angusto, marginem versus sese dilatanti separatum.

Spiraculum facillime distinguendum, juxta coxam quartam externe situm, oblongum, marginem ante-

riorem corporis juxta coxam secundi paris trabecula forti, elevata attingens. Pedum par primum gracile,

unguibus carens, antenniforme, longum, setis sparsis, que ad tarsi apicem magis numerose apparent,

munitum. Secundum et tertium pedum paria fortia, fusiformia, inermia, setis solum munita, que in

32 ACARIDEA.

femorum dorso spinas simulant. Cuticula ad earum basin in dentis formam paullulum protrusa.

Femora quarti paris supra tuberculis quatuor «quidistantibus munita sunt, ex quibus sete fortes spini-

formes nascuntur ; subtus apicem versus dentes tres fortes gerunt. Cetera articula setis sparsis munita,

ex quibus una ad apicem articuli quarti, altera ad apicem quinti articuli longiores sunt. Epistoma

magnum, triangulare, supra transverse compressum, antice paullo deflexum, apice in angulum acutum

paullo producto, eandem texturam microscopicam exhibens quam scuta ventralia. Ab animalculo vivo

epistoma ad latera nec non sursum deorsumque capitis instar movetur. Palpi longi, teneri, setis sparsis

quee in apice sexti articuli magis numerose sunt, muniti. Hypostoma in utroque latere dentem apice

obtuso ostendit, in medio in lingulam longam, angustam, quadrilobatam, setulosam, pellucidam, desinit.

Mandibule fortes, earum chela longa, angusta, brachiis ambobus denticulatis ; in brachio fixo circa 12,

in mobili circa 14 dentes observavi. Chele brachium fixum in superficie interna scopa pellucida setulosa

superatur que ex chela media nasci videtur ; apex brachii mobilis membranula tenuissima, hyalina, con-

voluta (mappula apud Thorell) ornatur, cujus margo subtilissime serrulatus est. In superficie laterali

brachii chele mobilis arbusculi tres racemosi nascuntur, quorum duo sub apice brachii siti, et valde

inter sese approximati sunt, tertius paullo distans, in medio chele fere situs. Ad basin externam brachii

mobilis fasciculus ex spinulis hyalinis confectus difficillime observatur. Dentes labiales longi, curvi,

integri.

Long. corp. cum epistom. 3°5 millim., sine epistom. 3 millim.; lat. max. 2—2°25 millim.

@. Corpus ovatum, antice truncatum, supra convexulum. Scutum dorsuale integrum, modice nitidum ob

foveolas impressas, ex quibus setule breves, suberecte nascuntur, oblique retrospicientes. Limbo albido

ad latera et postice a scutis ventralibus separatur. Color lete brunneus. In utroque latere prope mar-

ginem scuti dorsualis series setarum longarum inserta est. Textura microscopica e sulculis anastomosan-

tibus confecta, qui scutum totum areolis oblongis irregulariter reticulant, sicut in maris scutis ventralibus.

Venter in medio convexus, lateribus in coxarum regione depresso-concavis. Scutum sternale angustum,

antice et postice rectum, lateribus ob coxarum insertionem sinuatis, a scutis lateralibus interstitio angusto,

a scuto anali interstitio lato albicanti discretum. Inter coxas secundi atque tertii pedum paris orificium

genitale situm est, magnum, subpentagonum, margine postico inerassato. Scutum anale margine antico

recto, lateribus atque margine postico rotundatis, orificium anale in medio situm. Scuta lateralia coxifera

ab anali interstitio albido lato separata, postice angulatius protracta, apice rotundata. Epistoma, palpi

et pedes sicut in mare. Hypostoma in medio in lingulam quadrilobatam hyalinam productum, dentibus

lateralibus, qui in mare adsunt, carens; sulculo laterali sinuato, qui palporum socculum a labii trunco

separat. Palpi labiales longi, graciles, apice acuto, curvo, margine interno dente uno seu duobus. Man-

dibule sicut in mare, excepto brachio mobili chele, qui numerum minorem dentium prebet.

Long. cum epistom. 2°5 millim.; lat. max. 1:25 millim.

Hab. GuatEMaLA, Aceituno, Guatemala city, Zapote (Champion), Retalhuleu (Stot

In regione “ Cholhuitz,” hanc speciem in coleoptero-pectinicorni “Proculo goryi” deno-

minato parasitam inveni.

é. Body longer than broad, rounded behind, truncate at its anterior margin, much

depressed, smooth and shining; a few hairs are placed near the anterior margin, and a

row of six or seven obliquely inserted long bristles adorn the hind margin on each

side; colour light reddish-brown, in some individuals darker than in others; the

dorsal plate is separated from the ventral pieces by a whitish border on its side- and

hind-margins, and shows a minute sculpture consisting of small, irregularly polygonal

are with a few impressed points between them; ventral surface convex in the middle,

depressed at the sides, smooth, its border whitish and very narrow. Sternal plate

narrow ; rather long, smooth; its anterior margin truncate, its hind margin rounded.

Genital orifice situated between the coxe of the 2nd and 3rd pairs of legs, small,

circular. The sternal plate has two grooves at the hind margin, one on each side, out

MEGISTHANUS, 33

of each of which a strong hair arises; the grooves are encircled by an apparently

elevated broad whitish border, the border showing a microscopical granulation.

These characters are peculiar to the male sex of the genus Megisthanus, and are

wanting in the female; the colour of the sternal plate itself is much lighter than that

of the anal plate, and it is somewhat irregularly distributed—darker on the anterior

and lateral parts, lighter on the middle; the anal orifice is situated in the middle of

the anal plate. The side-plates extend beyond the hind coxe, forming a rounded angle

at their end. ‘The anterior legs are antenniform, long, and without claws; at the top

of the tarsi there are some densely-set tactile hairs. The second and third pairs of

legs are strong, somewhat fusiform, bearing on the back of the femora some spine-

like hairs. ‘The posterior femora have on the back an equidistant row of four spine-

like hairs and on their lower surface three strong, short, blunt teeth. The remaining

joints of the legs are irregularly set with hairs. The epistome forms a large triangular

hood, which is convex above and ends in a short acute angle: during life this piece

can be moved upwards and laterally; it hides the oral parts but imperfectly, as it is

surpassed in length by the palpi and, sometimes, by the upper part of the mandibles.

The palpi are long and simple, sparingly set with hairs, which are more numerous at

the top of the fourth and fifth joints. The margin of the hypostome bears a blunt

tooth on each side, and its middle projects into a transparent quadrilobate tongue-like

piece. The mandibles are strong, their chele rather narrow, bearing numerous irre-

gular teeth on the inner edge; on the inner surface of the fixed branch of the chela

a transparent narrow brush projects a little over the top of the mandible ; the movable

branch seems to be enveloped at the top in a small, transparent, irregularly-folded

membrane, the border of which is serrulated; on the lateral surface of the movable

branch there project three transparent appendages, each of which bears some finger-

like ramifications, and at the base there is a transparent cluster of small spinules.

2. Body ovate, its anterior margin truncate, slightly convex on the dorsum; dorsal

plate but moderately shining, rather coarsely punctured, a short semi-erect bristle

arising from each puncture; colour reddish-brown, the border of the dorsum whitish.

On each side of the dorsal plate, along its lateral margin, a row of long bristles is

inserted. The microscopical texture is similar to that of the ventral pieces and hood

of the male; it consists of a network of fine anastomosing furrows, which leave long,

narrow, irregular aree between them. Ventral surface convex in the middle, depressed

and concave at the sides. The whitish interstice between the sternal and lateral

plates is narrow, that between the sternal and anal plates being broader. ‘The genital

orifice, which is comparatively large and pentagonal, lies between the 2nd and 3rd

pairs of coxe. The anterior margin of the anal. plate is straight, its side-margins being

rounded; the anal orifice is situated in the middle of the plate. The lateral plates

project into an obtuse angle behind the hind coxe. Epistome and palpi as in the

male. The hypostome bears no lateral tooth; the tongue-like piece is formed as in

BIOL. CENTR.-AMER., Arachn. Acar., Vovember 1892. F*

34 ACARIDEA.

The movable branch of the chele has fewer teeth than in the male; but

the fixed branch and appendages are similarly formed.

This is the largest Gamasid known as yet from Central America. In the Cholhuitz

district near Retalhuleu I found it parasitical upon a very large pectinicorn-beetle,

Proculus goryi, Guér.; but it cannot be confined to this species only, as the genus

Proculus is not known to occur in the localities where Mr. Champion obtained his

It is perhaps parasitic on other Passalide.

the male.

specimens of WM. gigantodes.

2. Megisthanus armiger. (Tab. XIX. figg. 1, 1 ae, 2.)

Megistanus (sic) armiger, Berlese, Bull. Soc. Ent. Ital. xx. p. 204, t. 9. figg. 1, 1 @ (1888).

Hab. Mexico, Jalapa (Hége).—Paracuay, Rio Apa.

Among the dried specimens of Gamaside received from Messrs. Godman and Salvin

there is one male Megisthanus, collected by Herr Hoge at Jalapa, which I believe to

belong to the above-named species, as it coincides with the description in all its essential

characters, as well as in the measurements, though it differs from it in some minor

details.

The differences are as follows :—

Specimen ( 6) from Jalapa (Mexico).

Scuti dorsualis superficies pilis brevibus e foveolis

prorumpentibus nec non punctulis impressis

ornata. In dorsi medio area oblonge tri-

angularis sulculo lineari circumscripta adest.

Ante scutum sternale scutulum prosternale, parvum,

transversum, medio longitudinaliter partitum

situm est.

Scutum sternale postice rotundatum, anterius ex-

cavatum. Scutum ventrale sat ab anali (trans-

verso quadrilatero) discretum.

Margo metapodiorum internus excavatus.

Scuta ventralia omnia setulis brevibus vestita.

Femora tertii paris inferne calcaribus tribus fere

obsoletis, quarti paris calcaribus quatuor bre-

vibus obtusis aucta.

Cornieuli labiales curvi.

Trochanter secundi paris superne inermis.

Cuticula in articulis quarto et quinto secundi, tertii

et quarti pedum paris ante apicem in dentem

squamiformem subtus sublevata.

Articulus palporum secundus dente brevi ante api-

cem subtus armatus.

Specimen (3) from Rio Apa (Paraguay),

as described by Mr. Berlese.

Scutum dorsuale et margines pilis curtulis vestita.

(Nothing more mentioned.)

(Not mentioned.)

ee eeee rotundatum, in medio tamen sinuatum, anterius

truncatum. Scutum ventrale ....... parum ab

anali (triangulari, vertice infero) discretum.

(Straight in Berlese’s drawing.)

Metapodia et scutum ventrale setis vestita, cetera nuda.

Femora tertii et quarti paris inferne calcaribus tribus

validis aucta.

Corniculi labiales recti.

Trochanter secundi paris superne spina valida armatum.

(Not mentioned.)

CELZNOPSIS. 35

CELANOPSIS.

Celenopsis, Berlese, Acari, Myr., et Scorp. Ital. fasc. xxxi. no. 5 (1886).

Diplogynium, Canestrini, Atti Soc. Ven.-Trent. xi. p. 101 (1888).

1. Celenopsis uropodoides, sp.n. (Tab. XVI. figg. 4-4 d, and Tab. XIX. figg.

3, 3a, 6,2.)

3 latet.

. Corpus oblongo-ovatum, depressum, supra minime convexum, postice indistincte acuminatum. Scutum

dorsuale limbo angustissimo, subnitidum, setulis brevibus in superficie et in margine suberectis munitum.

Color badius. Sculptura microscopica e sulculis anastomosantibus confecta, qui areolas oblongas irregu-

lares circumscribunt. In harum areolarum medio puncta seriatim disposita impressa sunt. Palpi et

pedes marginem corporis superant. Superficies ventralis depressa, eandem structuram microscopicam

sicut dorsualis preebens. Scutum ventrale magnum, postice acuminatum, marginem posticum corporis

non attingens, orificium anale prope apicem ferens. Coxe utriusque lateris approximate. Inter coxas

secundi atque tertii pedum paris orificium genitale (a clarissimo hujus generis auctore “ epigynium ”

appellatum) in parte anteriore scuti ventralis situm est, magnum, subpentagonum, antice latum, angulo

postico rotundatum. In epigynio distinguenda sunt :—(1) crista epigynica jugiformis, lateribus deflexis,

transversa, antice arcuata ; (2) valva vulve utriusque lateris aleformis, interne atque antice rotundata,

ad angulum internum anticum et prope marginis externi medium seta munita; (3) scutum parvum tri-

gonum a margine postico epigynil inter valvas utriusque lateris paullo prodiens; (4) fulcra vulva clavi-

formia, obliqua, arcuata. Ante epigynium scutum sternale hexagonum situm est, cuius margo anterior

excavatus, lateralis in angulum rotundatum productus est. Ante angulum et prope marginem posticum

in utroque latere setula inserta est. Scuta lateralia angusta, longa, prope marginem corporis posticum

rima triangulari angusta, albida separata. Spiraculum parvum, prope coxas posticas externe situm.

Pedes primi paris graciles, eorum tarsus unguibus carens, longus, setis numerosis ad apicem tactilibus,

sicut articulus palporum extremus, munitus. Pedes ceteri inermes, crassiores, setulis muniti. Palpi

inermes, sat longi. Epistoma trigonum, apice in mucronem acutum desinens. Mandibularum chel

brachiis gracilibus, denticulatis ; dentes brachii mobiles ineequales ; ad apicem parvuli, conferti, infra inter

se distantes, majores, pauci; in brachio fixo subsquales, apicem versus magis conferti ac breviores.

Hypostoma in linguam antice rotunde truncatam desinens, ex qua processus duo longi setiformes nascuntur.

Corniculi labiales basi lata in cornu extrorsus curvum acutum pellucidum desinunt. Brachium mobile

membrana pellucida marginibus sinuatis longa imperfecte obtectum. Apparatus cibarius totus difficillime

eruendus.

Long. 0°75 millim. ; Jat. 0°50 millim.

Hab. British Honpuras, R. Hondo (Blancaneauz).

Male unknown. Body of the female ovate, depressed, moderately shining, bearing

some short suberect hairs on all parts and showing a microscopic texture, consisting of

a network of very fine irregular anastomosing furrows, which leave long irregular spaces

between them, each space having a series of impressed points. The ventral plate is

large and acute behind, and does not reach the end of the body. Anal orifice small,

oblong, situated in the posterior angle of the ventral plate. ‘The space between the

two rows of coxe rather narrow. ‘The genital orifice (called ‘ epigynium” by

Mr. Berlese) is situated in the anterior portion of the ventral plate ; it is large, some-

what pentagonal in shape, broad at its anterior margin, rounded behind. ‘The sternal

plate is hexagonal, excavate at its anterior margin, the lateral margin forming a rounded

angle. ‘The lateral pieces are long and narrow, separated from the ventral piece by a

F* 2

36 ACARIDEA.

narrow interspace ; at the end of the body there is a small triangular space between

them. The spiracle is small, distinctly visible, and situated outside the hind coxe.

The legs are without spines or teeth, and bear only some hairs and bristles, which at

the top of the first pair of tarsi (and on the palpi) are long and more thickly set than

on the other joints. The epistome is triangular and protrudes from under the anterior

margin of the dorsal plate as anacute point; it imperfectly covers the mandibles, the

branches of which are irregularly denticulated.

Several specimens of this species, which is closely allied to the South-American

C. subincisa, Berlese, were collected at Rio Hondo by M. Blancaneaux.

2. Celenopsis megisthanoides, sp.n. (Tab. XIX. fig. 4, and Tab. XX. figg. 1,

1 a, b, 2.)

3 latet.

2. Corpus ovatum, depressum, antice et postice declivum, postice subacuminatum, antice, propter epistomatis

apicem, in angulum acutum desinens, lateribus in regione humerali sinuatis. Color clare badius. Scutum

dorsuale integrum, antice truncatum, ejus margo in lateribus et in margine posteriore ; limbo angusto albido

ab scutis ventralibus separatum, setis sat longis sparsis in superficie ornatum. Scutum sternale parvum,

transversum, inter coxas primi paris situm, antice recte truncatum, lateribus et margine postico sinuatis.

Scutum ventrale magnum, marginem posticum fere attingens, in eius parte anteriore vulva, rimam bifidam

simulans, sita est. Pedes omnes setulis sparsis muniti fere inermes, exceptis femoribus quarti paris

quee calcaribus tribus valde obtusis et seta valida basi approximata armata sunt, nec non tarso secundi

paris qui ad apicem juxta unguium pedunculum dentem curvum exhibet. Pedes antici longi, graciles,

ceteri crassiores, in eorum femorum dorso sete duz valide adsunt. Epistoma trigonum, declivum, antice

acutum, ad eius basin in margine scuti dorsualis seta fortis in utroque latere adest. Corniculi labiales

longe, ensiformes, extus recurvi, dentibus carentes. Inter eorum basin atque hypostoma processus spatu-

liformis acutus transparens adest. Hypostoma in linguam longam, angustam, tripartitam desinens.

Chelarum brachia longa, angusta, irregulariter denticulata, brachium mobile dentem fortiorem latum prope

basin exhibens. Palpi setigeri, inermes.

Long. 1°25 millim. ; lat. 0°75 millim.

Hab. Panama, Bugaba (Champion).

Male unknown. Body of the female ovate, depressed, somewhat acuminate behind,

the lateral margin in the region of the shoulders somewhat sinuated ; anterior border

of the dorsal plate truncate, bearing a strong bristle on each side over the basis of the

epistome ; the lateral and hind margins of the dorsal plate show a narrow whitish

border; the dorsal surface bears some comparatively long but thinly-set hairs. The

sternal piece is small, its anterior margin truncate, the lateral and hind margins sinu-

ated; it occupies the space between the first and second pairs of coxe. The ventral

plate is large and almost reaches the hind margin of the body. The vulva is situated

in the anterior portion of the ventral piece ; it forms a sort of bifid fissure. The fore

legs are long and slender, the other legs shorter and thicker ; all of them are without

spines or teeth, except the second pair, which bear a small curved tooth at their top,

and the femora of the hind pair, which underneath bear a row of three somewhat blunt

teeth ; between the base of the hind femora and the first of these teeth there is a

CELZANOPSIS.—PACHYLALAPS. 37

strong bristle, ‘The labial horns are long and slightly curved, in the shape of the

letter § reversed ; between their bases and the hypostome there is another process, the

top of which forms an acutely-pointed transparent foliole or spatula; the hypostome

ends in a long and narrow tongue-like process.

Two specimens.

. PACHYL/AELAPS.

Pachylelaps, Berlese, Acari, Myr., et Scorp. Ital. fasc. li. no. 10 (1888).

1. Pachylelaps heros,

Pachylelaps heros, Berlese, Bull. Soc. Ent. Ital. xx. p. 196, t. 8. figg. 2, 2 a-e.

Var. mexicanus. (Tab. XIX. figg. 2, 2 a-e.)

3. Corpus late ovatum, supra convexulum, antice subangulatum, postice rotundatum, antice et postice decli-

yum. Color scutorum, rostri pedumque badius, membranarum conjunctivarum albicans. Scutum dorsuale

integrum, fere nudum, dense reticulatum, setis sparsis in parte anteriore et in marginibus munitum, a

margine postico membrana conjunctiva setulas numerosas gerente separatum. Pedes primi paris graciles,

articulis plus minusve cylindricis, setis sparsis munitis, tarsis unguiferis. Pedes secundi paris crassissimi,

dentibus seu calcaribus ut sequitur armati; dentes breves duo in coxée apice adsunt, trochanter est

inermis, femur calcari fusco, recto, indistincte tridentato armatum, genu atque tibia tuberculum parvum

bigibbosum gerunt, tarsus ante apicem dentem fortem obtusum preebet. Coxee tertii paris dentibus duobus,

uno centrali, altero marginali, brevibus munite, trochanteres ad apicem dentes duos juxtapositos desupra,

tertium infra ferunt, ceteri articuli pilis exceptis inermes. Coxee quarti paris dentibus duobus brevibus sicut

in tertio pari munits, trochanteres ad apicem desupra dentes duos subacutos juxtapositos, infra dentem

unum obtusum gerunt, femur ad basin et in apice dente armatum, ceteri articuli, tarsis inermibus exceptis,

dentibus duobus armati. Scutum sternale cum ventrali concretum reticulatum, postice truncato-rotun-

datum, marginem posticum non attingens, ab anali separatum. Scuta metapodica parva, trigona angulis.

rotundatis. Scutum anale parvum, trigonum. Orificlum genitale parvum in margine anteriore scuti

ventralis situm. Inter scutum ventrale et hypostoma lobulus parvus lingueformis, setulis duabus ad

apicem munitus mobilis insertus est. Chele mandibularum modice, dentibus paucis armatz, in brachio

mobili processus longus ad chele basin in spiram pluries convolutus insertus est. Corniculi labiales dis-

tincte biarticulati, eorum articulus postremus ante apicem dentem parvum gerit. Palpi inermes, excepto

articulo primo inferne calcar robustum ferente.

2. Statura et colore maris; a mare precipue differt pedum pari secundo ceteris haud crassiore, inermi, nec non

quarto pari calearibus carente, inermi.

Long. 2 millim.; lat. 1-5 millim.

Hab. Mexico, San Andres 'Tuxtla (Sad/é).

Body of the male broadly ovate, slightly convex, its anterior border forming a short

acute angle; colour of the hard plates, the rostrum, and legs light reddish-brown, the

connecting membranes whitish; the dorsal plate almost hairless, bearing only a few

bristles on its anterior and lateral borders; the bristles are longer and more thickly set

on the whitish membrane which connects the dorsal plate to the ventral pieces; the

dorsal plate shows a minute reticulation, consisting of a network of small polygonal

are; almost on the middle of the dorsal surface there are two slightly impressed

grooves. The first pair of legs are slender, their joints almost cylindrical, bearing some

38 ACARIDEA.

hairs, but without spines or teeth. The second pair of legs are very thick, the femur

especially, the latter bearing a strong, straight, slightly denticulated spine on the

middle of its under surface; the genu and tibia each bear a small tubercle, and

the tarsus is armed with a broad laminar tooth at some distance from the tip.

The third pair of legs are comparatively slender, without spurs, except a short one on

the upperside of the trochanter at the tip. The fourth pair of legs are longer than

the third, their trochanters bearing two teeth on the upper surface at the apex and a

short tubercle below; the femora bear underneath a tooth at their base and one at

their apex; the fourth joint has a blunt tooth and a short spine at its tip. The sternal

and ventral plates form but one piece of an irregular shape, which protrudes but little

behind the fourth pair of coxe and ends at some distance from the anal plate; this

piece has its side-margins excavated for the reception of the coxe, its posterior portion

being widened laterally and truncate behind; the anal piece is small, triangular; the

lateral pieces are large and bear the distinctly visible spiracle ; the metapodial piece is

small, of a triangular or rather oviform shape. The palpi are unarmed, except their

first joint, which bears a strong spur on the inner side. The labial horns are distinctly

two-jointed, and have a tongue-like process between them. The chele bear a few

strongly-marked teeth at their edges; from the centre of the movable branch a long

process issues, the end of which is rolled up somewhat spirally.

The female differs from the male in the following characters:—All the legs are

slender and, with the exception of the apical teeth of the trochanters, do not bear any

spurs or teeth; the sternal plate is separated from the ventral piece; there are no

metapodial plates ; and the dimensions of the body are a trifle smaller.

Two specimens, one male and one female, of this large Gamasid were collected by

M. A. Sallé at Tuxtla. Their affinity to P. heros, Berlese, from Brazil, is so remark-

able that I can only treat them as a variety of that species. The Mexican specimen

(¢ ) before me differs from Berlese’s description in the following characteristics :—

P. heros, typ. 3 (as described by Berlese). Var. meaicanus, 3.

Spur of the femur of the second pair thick, curved, Spur of the femur of the second pair straight, denticu-

with two teeth at the tip; spur of the genu,of late at its margins ; spur of the genu of the second

the second pair comparatively elevated, dis- pair short, rudimentary, forming only a tubercle ;

tinctly visible; tarsus of the second pair with- tarsus of the second pair bearing a distinctly visible

out a tooth at some distance from the apex ; compressed tooth at some distance from the apex ;

genu of the fourth pair bearing but one tooth genu of the fourth pair bearing two teeth—one

(not mentioned in the description, but present pointed, spined (like the lateral tooth), and one

in the drawing). blunt, on the ventral surface of the apex.

HOLOSTASPIS.—PTEROPTUS. 39

HOLOSTASPIS.

Holostaspis, Kolenati, Wien. ent. Monatschr. ii. p. 87, t. 1. figg. 1, 2 (1858); Canestrini, Prospetto

dell’ Acarofauna Italiana, p. 55 (1885). .

1. Holostaspis marginatus. (Tab. XX. figg. 2, 2 a-e.)

Acarus marginatus, Hermann, Mémoire Aptérologique, p. 76, t. 6. fig. 6.

Holostaspis marginatus, var. americanus, Berlese, Bull. Soc. Ent. Ital. xx. p. 195.

Hab. GuatemaLa, Retalhuleu (Stol/); Nicaracua, Chontales (Janson).—Sovru

AMERICA, Brazil, La Plata, Paraguay.

Two specimens of this classical Gamasus were collected by Mr. Janson at Chontales.

I have frequently met with it at Retalhuleu, where its various larval and nymphal stages

live as parasites on the common “ronron” or dung-beetle (Pinotus sp.), together with

the nymphs and larve of Gamasus fucorum, De Geer (coleoptratorum, auct.).

Subfam. DERMANYSSINA.

PTEROPTUS.

Pteropius, L. Dufour, Ann. Sciences Nat. xvi. p. 98 (1832).

The bats of Central America are, as well as those of Europe, infested by parasitical

mites of the genus Pteroptus, which attach themselves to the smooth skin of the

wings and the axillary cavity. But as my drawings are too incomplete to allow the

identification of the species, I do not reproduce them here, but merely state that this

subfamily is represented in Guatemala. |

Suborder II. ACARINA-ATRACHEATA, Kramer.

[Kramer, Grundziige zur Systematik der Milben, in Arch. fiir Naturg. xlii. p. 218 (1877).]

Fam. SARCOPTIDZ.

[Michael, British Oribatide, p. 50 (1884).]

Subfam. TV ROGLY PHINA.

[Trouessart, Les Sarcopt. plumicoles, 1° part. p. 6 (1885).]

In Guatemala I have occasionally observed the presence of free-living Tyroglyphi, as

well as of hypopial forms attached to the body of several species of flies (Muscide), ‘but

I have not taken exact notes as to any of them.

40 ACARIDEA.

Subfam. ANALGESINAL.

[Trouessart, Les Sarcopt. plumicoles, 1° part. p. 5 (1885). ]

MEGNINIA.

Megninia, Berlese, Acari, Myr., et Scorp. Ital. fase. iv. (1883).

1. Megninia pteroglossorum, sp. n. (Tab. XXI. figg. 5, 5a, 0.)

3. Corpus subovatum, colore ex albido-griseo, nitidulum, convexulum, Pedem paria anteriora inter se

eequales, breves. Pedes tertii incrassati, longi, abdominis marginem posteriorem superantes, articulo

ultimo acuto, unguifero, caruncula adhexsiva induto, ceteris articulis cylindricis. Pedes quarti breves,

tenues, in articulo ultimo ungues duo ferentes, abdominis marginem vix attingentes. Appendices anales

lamelliformes, acuti, margine interiore integro, exteriore incisuris duabus sat profundis sinuato. Pars

posterior appendicule utriusque lateris setas duas longas ferens, seta brevior in lobo inter incisuras con-

fecto ; longissima juxta basin appendicule externe sita. Disci adhewsivi prope marginem posticum ante

appendiculas in ipso abdomine siti, magni. Epimera primi pedum paris in linea mediana ad laminam

sternalem formandam sese conjungunt.

Long. corp. circa 0-5 millim.

Q nymphe. Corpore oblonge ovato, antice latiore, marginem posticum versus attenuatum, postice rotundatum.

Pedes breves, corporis margini inserti, sparse setigeri. Pedes anteriores crassiores, breviores, posteriores

tenuiores, longiores. Epimera primi paris in linea mediana sese tangentia, secundi paris brevia, libera.

Margo posterior abdominis integer, setis quatuor armatus, internis brevioribus, externis longioribus.

Long. corp. circa 9°5 millim.

Larva hexapoda corpore oblongo, margine integro, super pedum insertionem angulariter protracto.

Hab. Guatemata, Retalhuleu (Stol/). In remigum vexillis Pteroglosst torquati

parasita gregatim vitam degit.

Body of the male ovoid, greyish-white, transparent, shining, convex. Anterior pairs

of legs of equal length, short. Third pair of legs very thick, long, protruding over the

hind margin of the body, their last joint pointed, bearing claws, the other joints cylin-

drical. Fourth pair of legs short, slender, with two teeth on their tarsus, hardly

reaching the end of the body. The anal appendices are pointed, lamelliform, their

inner margin straight, their outer margin sinuated, with two profound incisures; the

posterior portion of the appendices bears two long bristles, and there is a short bristle

on the lobe between the two incisures; the adhesive discs are large and situated near

the posterior margin of the body before the appendices. The epimera of the fore legs

of both sides are united into a common sternal plate.

Body of the female (nymph) oblong, somewhat thinner towards the posterior end,

rounded behind. ‘The legs are short and inserted at the margin of the body; the two

first pairs are a little thicker and shorter than the hind pairs. The epimera are brown

and have the appearance of narrow hard bands; those of the fore legs of each side

reach the median line, those of the second pair remain separated, The hind margin

of the body bears four bristles; in young specimens it is a little excavated.

The hexapod larva is oblong, the side-margin forming a sort of angle over the

insertion of the legs.

MEGNINIA.—PTEROLICHUS. 4]

This species lives gregariously as a parasite in the wing-feathers of the “ Cucharon ’

(Pteroglossus torquatus) in the tierra caliente of Retalhuleu (Guatemala).

PTEROLICHUS.

Pterolichus, Ch. Robin et Mégnin, “ Mém. sur les Sarcoptides plumicoles,” Journ. de |’Anat. et de

la Physiologie, 1877, p. 398.

1. Pterolichus momotorum, sp.n. (Tab. XXI. figg. 1, la, b,¢; 2, 24,2.)

$. Corpus convexum, translucidum, ex albido griseum; marginum circumferentia irregulari inter coxas

secundi et tertii paris latus utrumque corporis ad lobi instar protrusum, lobulum anteriorem minorem

atque posteriorem majorem simulans. A basi tertii paris pedum usque ad basin appendicum analium

corpus crassitudine diminuit. Appendices anales magne, basi lata, margine externo integro, convexo,

margine interno irregulari, in medio rotunde exciso, sinuato. Appendieule apice sat obtuso, setis duabus

longis nec non spinis tribus brevibus munite. Disci adhesivi in appendicularum basi siti. Pedes omnes

inter se equales, eorum tarsus caruncula magna in peduncalo tenui inserta instructus. In dorsi medio

super coxas secundi pedum paris set quatuor, duc interns breves, due extern longer, site sunt. Spina

valida recta in latere corporis ante coxas tertiorum pedum. Palpi biarticulati. Mandibule breves, crass,

earum chels dentibus paucis brevibus armate. In facie ventrali scutum sternale parvum, inter coxas pedum

anteriorum, atque scutum ventrale, ab illo interstitio clariore separatum, oblongum, distinguuntur. Epi-

mera angusta, linearia, colore brunneo. Epimera primi et secundi paris oblique versus lineam medianam

tangentia, sed sese non attingentia, apicibus late separatis. In ventris medio trabecula semicircularis

ante orificium genitale sita.

Long. corp. circiter 0°5 millim.

@. Corpus majus atque longius quam in mari, lateribus ad lobi instar protrusus, post coxas quarti paris cylin-

dricus, lateribus parallelis, apice rotundato, in medio rotunde exciso, juxta excisionem in utroque latere

setee dus longe et spine breves due adsunt. Epimera, sete dorsi, palpi, mandibule atque pedes ut

in mari.

Long. corp. circiter 0°5-0°75 millim.

Hab. Guaremata, Retalhuleu (Stol/), in vexillis remigum Momotus lessoni gregatim.

Body of the male convex, transparent, of a milky-whitish colour; the side-border is

irregular and projects between the second and third pairs of legs in the form of a

bipartite lobe; from the base of the third pair of legs the abdomen diminishes in size.

The anal appendices are large, broad at their bases, convex externally, their inner border

irregularly sinuated, with a round excavation in its middle; they are rather blunt at

their tip and each bears two long bristles and three short spines; the adhesive discs

are situated at their base. On the anterior portion of the back four bristles are

inserted, and the side-margin bears, at a short distance from the third pair of coxe, a

straight short spine. The legs are of about equal length and shape, each tarsus bearing

a large caruncle. The palpi are two-jointed, and the mandibles are short and thick,

their chele armed with a few short teeth. The ventral surface is divided by a clearer

interstice into a smaller sternal piece, occupying the space between the anterior coxe,

and a larger and oblong ventral piece. The epimera form narrow, pointed stripes of a

brownish colour, which are directed from the side-margin towards the median line of

the body.

BIOL. CENTR.-AMER., Arachn. Acar., January 1823. a*

42 ; ACARIDEA.

The female differs from the male by its larger size and the more oblong ‘shape of the

body, the abdomen being cylindrical from the hind legs, and by the want of the anal

appendices. The abdomen is simply rounded at the apex, the hind margin bearing a

small round excision in its middle. The legs, the dorsal hairs and lateral spines, the

epimera, the palpi, and mandibles are as in the male. A chitinized stripe of brownish

colour and semicircular shape is situated transversely before the genital orifice.

This species lives gregariously in the wing-feathers of the ‘* Pajaro bobo” (Momotus

lessont). In running, the female takes the lead and draws the smaller male after her.

In the act of copulation the female places her abdomen above the anal appendices of

the male. (In figg. 1, 2 this connection already appears loosened a little.) I

observed this species in November 1880.

P. momotorum bears, by the form of its anal appendices, a remarkable affinity to

P. phylloproctus, Trouess. et Mégn., which inhabits the Haliéetus leucogaster of the

Indian and Chinese seas. It seems to be even more closely allied to this species than

to P. biemarginatus and P. ramphastinus, Trouess. et Mégn., which are parasites of

various South-American birds.

PROCTOPHYLLODES.

Proctophyliodes, Robin et Mégnin, Mém. sur les Sarcoptides plumicoles, p. 629 (1877).

1. Proctophyllodes sialiarum, sp.n. (Tab. XXI. figg. 3,¢; 4, 4a-¢, 2.)

3. Corpus minimum, albidum, translucidum, circiter quarta parte minus quam in femina, sat longum, paul-

lulum angustius quam in femina, pedes anteriores atque posteriores interstitio longo segregati. Omnes

pedes inter sese fere sequales, breves, Maxima latitudo corporis ante coxas tertii paris. Ante eas spina

recta prope marginem inferne sita est. Post pedes tertii paris corpus crassitudine diminuit. Appendices

anales sat breves, carnose, conics, separate incisura profunda, in quavis appendice 3 sete diverse longi-

tudinis adsunt. Disci adhesivi in appendicum basi prope marginem internum inferne siti. Mandibule

breves, chelarum brachia longa, angusta, et ita curva ut clausa apicibus solum sese attingant.

Long. circiter 0°25-0°5 millim.

2 adulta. Corpus majus quam in mare. In abdominis apice furca carnosa adest, que inferne prope marginem

convexum externum in utroque latere spinam lanceolatam sat longam fert. Furce apex cujusque lateris

in appendicem longam, sinuatam acutissimam desinit. Epimera primi paris utriusque lateris in media

regioni sternali sese conjungunt, secundi paris angulariter retrorsum fracta late discreta remanent. In

corporis latere, paullulum post medium interstitii inter pedes secundi et tertii paris seta sat longa inserta

est. Inventre medio trabecula transversa arcuata seu semicircularis adest, que in utroque latere brachio

longo annulum coxe tertie attingit. Mandibule ut in mari.

Long. circiter 0°5 millim.

2 nympha. Abdomen in appendicem conicam, carnosam, incisura bipartitam desinit, que in superficie externa

utriusque lateris spinam lanceolatam sat longam et in apice setam longam gerit.

Larva hexapoda minima, jam rudimenta appendicum analium adulte preebet.

Ovum longum, fusiforme, translucidum, sat magnum, ad cribri instar perforatum.

Hab. Guatemata, Retalhuleu (Stol/), in remigibus Sialia sialis gregatim.

Male very small, long and narrow, of a whitish, somewhat transparent colour, about

one-fourth smaller than the female. The two anterior pairs of legs are separated by a

eo)

PROCTOPHYLLODES, 4

wide interstice from the third pair. The body is broadest at some distance in front

of the third pair of coxee; from the third pair of legs it diminishes in size, and ends in

two fleshy appendices, of a short conical shape. The appendices are separated by a

deep incision ; each of them bears three bristles; the adhesive discs are situated near

the inner margin and at the base of the anal lobes. The mandibles are short ; the

branches of the chelz are long, slender, and curved, and when closed they touch each

other with the points only.

The adult female is a little larger than the male. Its abdomen terminates in a

fleshy fork, each point of which bears a lancet-like spine underneath and ends ina

narrow, acutely-pointed, somewhat curved blade. The apices of the first pair of

epimera of each side touch each other in the sternal region; those of the second pair

remain widely separated, and are, at about two-thirds of their length, angularly inflected

and directed backward. On the side of the body, somewhat behind the middle of the

interstice between the second and third pairs of legs, a long bristle is inserted, and

underneath, near the third pair of coxe, stands, as in the male, a straight, lancet-like

spine, which is usual in this genus. A little behind the middle of the ventral surface

there is a semicircular transverse trabecula in front of the genital orifice; its branches

are continued backward and united with the coxal circles of the fourth pair. ‘The

mandibles are as in the male.

In the nymph the abdomen terminates in a conical process, which by a narrow fissure

is separated into two lobes, each lobe bearing on its outer edge a lanceolate spine

and a long bristle on its top.

The hexapod larva is very small, and shows, though in a rudimentary state, the anal

appendices of the adult.

The eggs are long, comparatively large, fusiform, transparent, and cribrated.

Nore.—Several years have elapsed since the publication of this memoir was com-

menced in December 1886. In the meanwhile I have become better acquainted with

the Acarid-fauna of Europe and some other countries. The clearer insight into the

leading features of the geographical distribution in general which I have thus

acquired, and of which I have given a résumé in the ‘‘ Introduction,” has made

me sceptical with regard to the validity of some of the species described in this

work. As an excuse for the synonymical errors into which I may have fallen in

some instances, I may be allowed to plead the many difficulties which the study of

Acarids offers to the naturalist in a tropical country, in consequence of the extreme

delicacy of the soft-bodied species and their great liability to rapid changes of form

and colour. Moreover, owing to the unfortunate circumstance that I only brought

a* 2

44 ACARIDEA.

with me to Europe drawings and more or less fragmentary notes of many of the soft-

bodied species, I had no opportunity of comparing the types themselves with European

forms and the descriptions of authors.

These remarks will perhaps incite future inquirers to fix their attention more

particularly on these fragile forms.

The list which follows contains the names of all the species of Acari hitherto

described from Mexico and Central America. In it I have incorporated certain

corrections and criticisms, which will be found under the names of the species to which

they severally refer.

List of the Species of Acaridea hitherto described from Mexico and Central America.

Suborder I. ACARINA-TRACHEATA.

TROMBIDIUM, Latr.

1. Trombidium mexicanum.

Trombidium mexicanum, Stoll, antea, p. 1, Tab. I. figg. 1-1 d.

Hab. Mexico, Presidio.

This undoubtedly bears a remarkable affinity to 7. dubrweilli, A. Dugés; yet it

cannot be considered to coincide with that species, as it seems to differ not only in size,

but also in some minor details as regards the disposition of the hairs and the form of

the palpi and mandibles.

2. Trombidium dubrueilli.

Trombidium dubrueillii, Alf. Dugés, La Naturaleza, vii. p. 806, t. 8. figg. 1-10.

Hab. Mexico, Guanajuato, Tupataro.

8. Trombidium hispidum.

Trombidium hispidum, Stoll, antea, p. 2, Tab. IL. figg. 1-1 d.

_ Hab. GuatEmata, Retalhuleu.

4. Trombidium nasutum.

Trombidium nasutum, Stoll, anted, p. 2, Tab. IIT. figg. 1-lg.

Hab. GuateMALA, Retalhuleu.

TROMBIDIUM.—ACTINEDA. . 45

5. Trombidium quinque-maculatum.

Trombidium quinque-maculatum, Stoll, antea, p. 3, Tab. IV. figg. 1-le.

Hab. GuatTEMALA, near the city.

6. Trombidium muricola.

Trombidium muricola, Stoll, anted, p. 5, Tab. II. figg. 3-36.

Trombidium guayavicola, Stoll, antea, p. 4, Tab. IL. figg. 2-2.

Hab. Guatemaa, Retalhuleu, Antigua.

T. quayavicola and T. muricola are, I believe, only colour-varieties of one and the

same species. I was led into error by the different habitats, and by the discrepancies

between my original drawings, which were made, at a year’s interval, at different

places, Retalhuleu and Antigua. I propose to drop the name of 1. guayavicola and

to keep only that of 7. muricola.

7. Trombidium trilineatum.

Trombidium trilineatum, Stoll, antead, p. 4, Tab. I. figg. 2-2c.

Hab. GuateMata, Antigua.

8. Trombidium albicolle.

Trombidium albicolle, Stoll, anted, p. 5, Tab. I. figg. 3, 3 a.

Hab. GuaTEMALA, Antigua.

RHYNCHOLOPHUS, Duges.

1. Rhyncholophus erinaceus.

Rhyncholophus erinaceus, Stoll, anted, p. 6, Tab. IV. figg. 2-2 d.

Hab. Guatemata, Antigua.

Fam. ACTINEDIDA,

ACTINEDA, C. L. Koch.

1. Actineda baccarum.

Acarus baccarum, Linn. Syst. Nat. 10th edit. p. 617.

Acarus vitis, Schrank, Enum. Ins. Austr. indig. p. 519.

Trombidium cornigerum, Herm. Mém. Aptérolog. p. 38, t. 2. fig. 9.

Actineda flaveola, Stoll, antead, p. 7, Tab. V. figg. 1, la.

Actineda antiguensis, Stoll, anted, p. 7, Tab. V. figg. 2-2 d.

Actineda retalteca, Stoll, antead, p. 7, Tab. V. figg. 3-3 ¢.

Hab. Evrope.—Guatemata, Retalhuleu, Antigua.—SouTH AMERICA.

46 ACARIDEA.

After having studied more attentively the European A. baccarum, L. (=cornigerum,

Herm.), I believe that the above-named Guatemalan forms are but varieties of

colour and age of this species, as I cannot find any tangible differences between my

original drawings and European specimens, except those of size and colour, which in

Actineda are of no value. ‘This view is confirmed by the circumstance that Berlese

has identified preserved specimens of Actineda from Rio Apa (Paraguay) and from

Buenos Ayres with the European species, with the remark “parum ab Europea

diversa”*. It therefore seems that A. baccarum, L. (=A. vitis, Schrank, =TZromd.

cornigerum, Hermann), is one of those fundamental and characteristic types which

occupy an extremely extensive geographical area, a fact I have discussed at length in

the “ Introduction” to the present memoir.

Fam. TETRANYCHIDA, Kramer.

TETRANYCHUS, Dufour.

1. Tetranychus guatemale-nove.

Tetranychus guatemale-nove, Stoll, antead, p. 8, Tab. VI. figg. 1-1 ¢.

Hab. GuateMALA, near the city.

2. Tetranychus dugesi.

Tetranychus dugesii, D. Cano y Alcacio, La Naturaleza, vil. p. 197, t. 2. figg. 1-5.

Hab. Mexico. On Medicago denticulata, Willd.

Fam. HYDRACHNIDA, Neuman.

The corrections in the synonymy of the species of this family described by me are

made on the competent authority of Herr Koenike of Bremen, who, at my request, has

favoured me with his opinion on them.

ATAX, Fabr.

1. Atax alticola.

Atax alticola, Stoll, antea, p. 9, Tab. VII. figg. 1-lg.

Atax septem-maculatus, Stoll, antea, p. 9, Tab. VIII. figg. 1-1 e.

* A. Berlese (Acari Austro-Americani, p. 11) identifies his American specimens with Acarus vitis, Schrank,

which he considers to be synonymous with Z’rombidium cornigerum, Hermann. But as Schrank himself, in

his description of A. vitis (Enum. Ins. Austr. indig. p. 519. no, 1067), says that it differs from A. baccarum,

L., only by the disposition of the hairs on the legs, I think that we must regard A. vitis, Schrank, and Acarus

baccarum, L., as belonging to one and the same species. |

ATAX.—LIMNESIA. AT

Atax septem-maculatus, var. ypsilon, Stoll, anted, p. 10, Tab. TX. figg. 1-1.

Hab. GuatTEMALA, near the city.

According to Herr Koenike, A. septem-maculatus and.its var. ypsilon are probably

nymphal stages of A. alticola.

2. Atax dentipalpis.

Atax dentipalpis, Stoll, anted, p. 10, Tab. X. figg. 1-ld.

Hab. GuaTEMALA, near the city.

This, according to the same authority, should be referred to the widely distributed

A. crassipes, O. ¥. Mull.

NESAA, Neuman.

1. Nesza alzatel.

Atax alzatei, A. Dugés, La Naturaleza, vi. p. 344, t. 8. figg. 1-19.

Hab. Mexico, Guanajuato.

This species has been ascribed by its author to the genus Atax.

2. Nesea guatemalensis.

Nesea guatemalensis, Stoll, anted, p. 11, Tab. X. figg. 2-25 (2), and Tab. XI. figg. 1-1 f (¢).

Hab. GUATEMALA, near the city.

3. Nesea numulus.

Nesea numulus, Stoll, antead, p. 12, Tab. XI. figg. 2-2 ¢.

Hab. GuatTEMALA, near the city.

LIMNESIA, Neuman.

1. Limnesia guatemalteca.

Limnesia yuatemalteca, Stoll, anted, p. 18, Tab. VIL. figg. 2-2 e.

Hab. GuaTeMALA, near the city.

From the form of the palpi, Herr Koenike considers this to be a nymph, probably

of the following species.

2. Limnesia longipalpis.

Limnesia longipalpis, Stoll, anted, p. 13, Tab. IX. figg. 2-2.

Tlab. GuaTeMALA, near the city.

48 ACARIDEA.

3. Limnesia puteorum.

Limnesia puteorum, Stoll, antea, p. 14, Tab, VII. figg. 3-3.

Hab. GUATEMALA, Antigua.

4. Limnesia leta,

Limnesia leta, Stoll, antead, p. 14, Tab. VIII. figg. 2-2 d.

Hab, GUATEMALA, near the city.

Fam, BDELLIDA,

BDELLA, Latr.

1. Bdella splendida.

Bdella splendida, Stoll, antea, p. 15, Tab. ITI. figg. 2-2 e.

Hab. GUATEMALA, near the city.

Fam. KUPODIDA.

SCYPHIUS, Koch.

1. Scyphius maniacus.

Scyphius maniacus, Stoll, anted, p. 17, Tab. VI. figg. 2-2 d.

Hab. Guatemata, Retalhuleu.

Fam. IXODIDA.

ARGAS, Latr.

1. Argas talaje.

Argas talaje, Guérin-Ménéville, Revue et Mag. Zool. 1849, p. 342, t. 9.

Hab. GuateMaua, Casas Viejas de Guastatoya.

2. Argas turicata.

Argas turicata, A. Dugés, La Naturaleza, vi. p. 195, t. 4a. figg. a 1-8.

Hab. Mexico, Guanajuato.

A parasite on hogs.

3. Argas megnini.

Argas megnini, A. Dugés, La Naturaleza, vi. p. 197, t. 4a. figg. B 1-8.

Hab. Mexico, Guanajuato.

This species is stated to attach itself to the skin in the ears of horses, cattle, and

even man.

ORNITHODOROS.—AMBLYOMMA, 49

ORNITHODOROS, Koch.

1. Ornithodorus coriaceus.

Ornithodoros coriaceus, C. L. Koch, Arch. f. Naturg. x. Bd. 1, p. 219, no. 1; Ubers. d. Arachniden-

. syst. Heft iv. pp. 12, 31, t. 1. figg. 2, 3.

Hab. Mexico (teste Koch).

Berlese, in his ‘ Acari Austro-Americani,’ p. 23, mentions Ornithodoros coriaceus,

Koch, from Rio Apa (Paraguay), but without entering into details.

IXODES, C. L. Koch.

1. Ixodes boarum.

Ixodes boarum, Stoll, anted, p. 18, Tab. XIII. figg. 1-le, and Tab. XIV. fig. 4.

Hab. GuateMaa, Retalhuleu.

2. Ixodes pygmeus.

Ixodes pygmeus, C. Lu. Koch, Arch. f. Naturg. x. Bd. 1, p. 233, no. 18; Ubers. d. Arachnidensyst.

Heft iv. pp. 22, 107, and t. 22. figg. 81a, b (2).

Hab. Mexico.—Braziu (teste C. L. Koch).

AMBLYOMMA, C. L. Koch.

1. Amblyomma mixtum.

Amblyomma mixtum, C. li. Koch, Arch. f. Naturg. x. Bd. 1, p. 227, no. 17; Ubers. d. Arachniden-

syst. Heft iv. pp. 74, 75, t. 13. figg. 47 (¢), 48 (2); Stoll, anted, p. 19, Tab. XII.

figg. 1-1i (¢), 2-25(¢).

Hab. Mexico (teste C. L. Koch); Guatemaua, Retalhuleu, Antigua; Nicaragua,

Chontales; Costa Rica, Caché.

2. Amblyomma dissimile.

Amblyomma dissimile, C. L. Koch, Arch. f. Naturg. x. Bd. 1, p. 225, no. 10 (8 2); Ubers. d.

Arachnidensyst. Heft iv. pp. 17, 64, 66, t. 12. figg. 837 (¢), 88 (9).

Hab. Mexico (teste Koch).

3. Amblyomma tenellum.

Amblyomma tenellum, C. L. Koch, Arch. £. Naturg. x. Bd. 1, p. 227, no. 16 (¢); Ubers. a.

Arachnidensyst. Heft iv. pp. 17, 78, 79, t. 14. fig. 51 (3).

Hab. Mexico (teste Koch).

4, Amblyomma ovale.

Amblyomma ovale, C. Li. Koch, Arch. f. Naturg. x. Bd. 1, p. 227, no. 20; Ubers. d. Arachniden-

syst. Heft iv. pp. 18, 79, 80, t. 14. fig. 52 (¢).

Hab. Mexico (teste Koch).

BIOL. CENTR.-AMER., Arachn. Acar., January 1893. H*

50 . ACARIDEA.

5. Amblyomma foreli.

— Amblyomma foreli, Stoll, antea, p. 21, Tab. XII. figg. 8-8 4, and Tab. XIV. figg. 8-3 d (2).

Hab. GuatTeMa.a, Retalhuleu.

6. Amblyomma crassipunctatum.

Amblyomma crassipunctatum, Stoll, antea, p. 22, Tab. XIV. figg. 1-1 h (3).

Hab. Nicaragua, Chontales.

7. Amblyomma sabanere.

Amblyomma sabanere, Stoll, anted, p. 23, Tab. XIV. fee. § 2-21 ‘ 2).

Haé. GUATEMALA, near Retalhuleu.

Fam. ORIBATIDEA.

Subfam. PTHROGASTERINA.

ORIBATA, Latr.

1. Oribata centro-americana.

Oribata centro-americana, Stoll, antea, p. 24, Tab. XV. figg. 1-1 f.

Hab. British Honpuras, R. Hondo, R. Sarstoon, Belize; GuatTemata, Antigua,

Guatemala city ; Panama, Volcan de Chiriqui.

2. Oribata rugifrons.

Oribata rugifrons, Stoll, antea, p. 25, Tab. XV. figg. 2-2 d (? nymph, Tab. XV. figg. 3-3 d).

Hab. British Honpuras, Belize ; GuatTeMa.a, Retalhuleu.

Subfam. APTEROGASTERINA.

HOPLOPHORA, C. L. Koch.

1. Hoplophora retalteca.

Hoplophora retalteca, Stoll, antea, p. 27, Tab. XV. fige. 4—4,f.

Hab. Guatemala, Retalhuleu.

Fam. NICOLETIELLIDZ.

NICOLETIELLA, R. Canestrini.

1. Nicoletiella neotropica.

Nicoletiella neotropica, Stoll, antea, p. 27, Tab. XVI. figg. 1-le.

Hab. GuateMaua, Retalhuleu.

UROPODA.—MEGISTHANUS. o1

Fam. GAMASIDA.

Subfam. UROPODINE.

UROPODA, Latr.

1. Uropoda moneta.

Uropoda moneta, Walck. & Gervais, Hist. nat. des Ins. Aptéres, iii. p. 221, t. 34. fig. 5.

Hab. Mrxico. Found as a parasite on Polydesmus mexicanus.

2. Uropoda echinata.

Uropoda echinata, Stoll, antea, p. 28, Tab. XVI. figg. 2-2.

Hab. GUATEMALA, Antigua.

3. Uropoda inequipunctata.

Uropoda inequipunctata, Stoll, antea, p. 29, Tab. XVI. figg. 3-3 d.

Hab. GuatEMALA, Retalhuleu.

4. Uropoda discus.

Uropoda discus, Stoll, antead, p. 29, Tab. XVII. figg. 4-4 c.

Hab. Guatemaua, Retalhuleu.

5. Uropoda centro-americana.

Uropoda centro-americana, Stoll, anted, p. 30, Tab. XVII. figg. 1-1f, and 2-2 5 (nymph).

Hab. Nicaracua, Chontales.

6. Uropoda piriformis.

Uropoda piriformis, Stoll, anted, p. 81, Tab. XVII. figg. 3-3 d.

Hab. Mexico, Jalapa.

Subfam. GAMASINA.

MEGISTHANUS, T. Thorell.

1. Megisthanus gigantodes.

Megisthanus gigantodes, Stoll, anted, p. 31, Tab. XVIII. figg. 1-1 d (2), 2-29 (2).

Hab. Guatemata, Aceituno, Guatemala city, Zapote, Retalhuleu, Cholhuitz.

2. Megisthanus armiger.

Megisthanus armiger, A. Berlese, Bull. Soc. Ent. Ital. xx. p. 204, t. 9, iv. fig.1; Stoll, antea, p. 34,

Tab. XIX. figg. 1-le(o).

Hab. Mexico, Jalapa.n—Paracuay, Rio Apa.

H* 2

52 | ACARIDEA.

CEL-AENOPSIS, Berlese.

1. Celzenopsis uropodoides.

Celenopsis uropodoides, Stoll, antea, p. 85, Tab. XVI. figg. 4-4 d, Tab. XIX. figg. 3-36 (2).

Hab. British Honpuras, R. Hondo.

2. Celeenopsis megisthanoides.

Celenopsis megisthanoides, Stoll, anted, p. 86, Tab. XIX. fig. 4, Tab. XX. figg. 1-1 b (¢ )s

Hab. Panama, Bugaba.

PACHYLAILAPS, Berlese.

1. Pachylelaps heros.

Pachylelaps heros, var. mexicanus, Stoll, antea, pp. 37, 38, Tab. XIX. figg. 2-2 e.

Pachylelaps heros, Berlese, Bull. Soc. Ent. Ital. xx. p. 196, t. 8. fig. 2.

Hab. Mexico, San Andres Tuxtla. [Typus: Matto Grosso, Brazil. |

HOLOSTASPIS, Kolenati.

1. Holostaspis marginatus.

Holostaspis marginatus (Hermann), Stoll, antea, p. 39, Tab. XX. figg. 2-2 d.

Hab. GuatemMaLa, Retalhuleu; Nicaragua, Chontales.—SoutH AMERICA, Brazil, La

Plata, Paraguay.

Suborder II]. ACARINA-ATRACHEATA.

Fam. SARCOPTIDA.

Subfam. ANALGESINA.

MEGNINIA, Berlese.

1. Megninia pteroglossorum.

Megninia pteroglossorum, Stoll, antea, p. 40, Tab. XXI. figg. 5-5 6b.

Hab. Guatemaua, Retalhuleu.

PTEROLICHUS, Robin et Mégnin.

1. Pterolichus momotorum.

Pterolichus momotorum, Stoll, antea, p. 41, Tab. XXI. figg. 1-15 (3), 2, 2a (2).

Hab. GuaTEMALA, Retalhuleu.

PROCTOPHYLLODES. 53

PROCTOPHYLLODES, Robin et Mégnin.

1. Proctophyllodes sialiarum.

Proctophyllodes siaharum, Stoll, antea, p. 42, Tab. XXI. figg. 3 (3), 4-4 (2).

Hab. GUATEMALA, Retalhuleu.

N.B.—I have noticed the presence of a few other genera in Guatemala, but my notes

and drawings respecting them are too fragmentary to allow specific determination.

These genera are: Linopodes, C. L. Koch, Gamasus, Latr. (sensu stricto), Pteroptus,

Duf., Zyroglyphus, Latr.

INDEX.

[Names in small capitals refer to Families &e. ; those in roman type to the chief reference to each species included in the work ;

those in italics to species incidentally mentioned, synonyms, &c.]

Page

ACARINA-ATRACHEATA .... 39,52

ACARINA-TRACHEATA...... 1, 44

Acarus baccarum oo... cece eee 46

MANGINATUS . rover ecenee 39

7 45, 46

ACTINEDA woe. eee cece eee 7,45

Actinedd vie eeccccecceeenes 46

antiguensis ............ 7

—— antiguensis ......... 00. 45

—— baccarum ...........0.. 45

DACCATUM voce ccc eeceeee 46

COYNUGETUM eae cecccee 46

flaveola............000. 7

Jlaveola vice cece cece 45

retalteca ...........00. 7

TEALLECH vei evcevcaecee 45

C1 45, 46

ACTINEDIDE.... eee. e eee 6, 45

AMBLYOMMA........0...0. 19, 49

Amblyomma wove cccceveces 18, 21

crassipunctatam ...... 22, 50

——dissimile .............. 49

— foreli .............00. 21, 50

—— mixtum.............. 19, 49

—— MXTUM 6 oe eee cece 21, 22

—— ovale ..............000. 49

sabaneree ..........0. 23, 50

tenellum .............. 49

ANALGESINE .........00. 40, 52

APTEROGASTERINE........ 27, 50

ARGAS woe ce sees eee teens 48

—— megnini................ 48

talaje.... cee eee eee ee eee 48

—— turicata.,............., 48

ATAX we cece cece eee e eee 9, 46

ALAL cece cece ceccneccuee 10, 47

alticola .............. 9, 46

AUICOlA oe eee cece eee 47

1 47

CYASSUPES eee eee cc cence 47

—-dentipalpis .......... 10, 47

septem-maculatus ...... 9

septem-maculatus .. 10,46, 47

Page

Atax septem-maculatus,

var. ypsilon .......... 10

septem-maculatus,

Var. YPSlOn... cc seceees 47

BDELLA ....... 0... 0000. 15, 48

Bdelld. ccc ccc cece cc cen 16

splendida .......... 15, 48

BDELLID! .........0006- 15, 48

CELENOPSIS ............ 35, 52

—— megisthanoides ...... 36, 52

SUDINCISH cece ccc cccccas 36

uropodoides ........ 35, 52

DERMANYSSINE ....--. 0000. 39

Diplogynium vivivvccccccccees 35

EUPODIDH ...........4.. 17,48

GAMASIDE... eee e eee eee 28, 51

GAMASINAE.... ec cece ee eee 31, 51

GAMASUS... ee ceeccc eee 39, 53

-—— coleoptratorum .......64. 39

—— fUcorum eee eeeccvnees 39

HOLosTASPIS ............ 39, 52

marginatus .......... 39, 52

—— marginatus, var. americanus 89

HOPLOPHORA ............ 27, 50

MULENS vce eccccccceceee 27

retalteca ............ 27,50

VOAUECA. Lee eee eee nee 26

HyDRACHNIDH............ 9, 46

IXODES ..............000. 18, 49

~-— boarvm .............. 18, 49

—— pygmeus .............. 49

TXODIDH oo... eee eee ee 18, 48

LIMNESIA ......... 0.00005 13, 47

guatemalteca ...,.... 13, 47

—— leta ..... eee eee 14, 48

Page

Limnesia longipalpis ...... 13, 47

puteorum ............ 14, 48

Dinopodes ic ie ccecccvcacces 53

Megistanus armiger ........4. 34

MEGISTHANUS ............ 31, 51

Megisthanus ....... 00 cee ee 33, 84

armiger...........0., 34, 51

gigantodes .......... 31, 51

MEGNINIA ........... 0000. 40, 52

pteroglossorum........ 40, 52

Muria oe ces 26

trimaculata ..... cece 26

NESHA wo. eee eee eee 11, 47

NCS@M. Lecce cece cece 12

alzatel oo... esse eee AT

guatemalensis ......., 11, 47

numulus ......... ... 12,47

Nicoletta. oo. c cc e eee 27

NICOLETIELLA ..........4. 27, 50

COTNULA Loe v ccc cceecnees 27

neotropica............ 27, 50

NICOLETIELLIDE .......... 27, 50

ORIBATA oo. eee eee eee eee 24, 50

centro-americana ...... 24, 50

rugifrons ............ 25, 50

TUGYTONS vee eecececeees 26

Oribate oo. cece cece e eee 24

ORIBATIDE .......-.0-00. 24, 50

ORNITHODOROS.............. 49

coriaceuS .............. 49

PACHYLELAPS .........04, 87, 52

—— heros.............0.. 37, 52

NEVO8 oo eee cee 38

—— heros, var. mexicanus.. 87, 88

—— heros, var. mexicanus .... 52

PROCTOPHYLLODES........ 42, 58

sialiarum ............ 42,53

PTEROGASTERINE ........ 24, 50

Page

Pterolichus biemarginatus 42

momotorum .......... 41, 52

MOMOLOTUM Lo. ceeceveee 42

—— phylloproctus.......00005 42

ramphastinus .......... 42

PTEROPTUS ........0000000- 39

Pteroptus vec cevvcccevcceees 53

RHYNCHOLOPHUS.......... 6, 45

Rhyncholophus .. 0.0.1.0 00s 16, 17

électoralis ........0.000 16

erinaceus ............ 6, 45

SARCOPTIDH......... 0.00. 39, 52

Sarcopttdes.... 0. cece eee 39

SCYPHIUS .............00. 17, 48

—— maniacus ............ 17, 48

INDEX.

Page

TETRANYCHIDE .......00 8, 46

TETRANYCHUS ........000, 8, 46

—— dugesi ....... ce eeeeeee 46

guatemalee-nove ...... 8, 46

TROMBIDIDE.........0000. 1, 44

TROMBIDIUM ....... 0.00005 1, 44

Trombtdiwm .occccvccceccees 16

albicolle ............ 5, 45

—— COYNUGEPUM ve veceeee 45, 46

dubrueillii.............. 44

guayavicola ............ 4

GJUAYAVICOIA vec vevevcees 45

hispidum ............ 2,44

—— mexicanum............ 1, 44

MEXICANUM vi cevevccucs 2,5

—— muricola .............. 5, 45

Page

Trombidium nasutum ...... 2,44

quinque-maculatum.... 3, 45

—— trilineatum .......... 4, 45

TYROGLYPHINE ............ 39

Tyroglyphus oo. cee cece eens 39, 53

UROPODA oo... cece ee eeees 28, 51

Ur0podd . sce. ccscceccceues 30, 39

CASSIACH vee eee e neces .. 30

centro-americana...... 30, 51

discus............0005 29,51

echinata ............ 28, 51

invequipunctata........ 29, 51

—— moneta ..........0..05. 51

piriformis .,.......... 31,51

UROPODINE ...........00. 28, 51

PRINTED BY TAYLOR AND FRANCIS, RED LION COURT, FLEET STREET