ICONES PLEUROTHALLIDINARUM

IX

SYSTEMATICS

OF

MYOXANTHUS

ADDENDA TO PLATYSTELE, PLEUROTHALLUS

SUBGENUS SCOPULA AND SCAPHOSEPALUM

(ORCHIDACEAE)

Missouri Botanical Garden

ICONES PLEUROTHALLIDINARUM

IX

SYSTEMATICS

OF

MYOXANTHUS

ADDENDA TO PLATYSTELE, PLEUROTHALLUS

SUBGENUS SCOPULA AND SCAPHOSEPALUM

nIMU

Missouri Botanical Garden

JAN 111993

MONOGRAPHS IN SYSTEMATIC BOTANY

from the Missouri Botanical Garden

Volume 44, November 1992

ISSN 0161-1542

Carlyle A. Luer

3222 Old Oak Drive

Sarasota, FL. 34239

Composed at 3222 Old Oak Drive, Sarasota, Florida

with WordStar 55

and a Hewlett Packard LaserJet Series D

using HP 33412AD and 33412AF

Printed in the United States of America by

Arcade Lithographing Corp., Bradenton, FL

CONTENTS

Myoxanthus pan . Frontispiece

Systematics of the genus Myoxanthus .1

Myoxanthus pan, Endres 315 12

Index to Myoxanthus 109

Addenda to Platystele 112

Addenda to Pleurothallis subgen. Scopula .120

Addenda to Scaphosepalum .124

MyoxanOuis pan, province of Vci

SYSTEMATICS OF THE GENUS

MYOXANTHUS (ORCHIDACEAE)

ICONES PLEUROTHALLIDINARUM

The close interrelationship of the species of Myoxanthus was recognized by

Lindley when he listed together those few known to him (albeit with others) in

section Aggregatae in his Folia Orchidacea Pleurothallis in 1859. The genus

was resurrected in 1982 when 38 species were counted, and amplified with

eight more in 1986. The addition of this latter group broadened the original

scope for Myoxanthus, but cellular morphology of the leaves has supported

their inclusion (Pridgeon, 1982). The cellular morphology is somewhat similar

in Dresslerella Luer. Grossly, Myoxanthus seems most closely related to

Pleurothallis snhgcnns Acianthera.

Although morphologically variable, both vegetatively and florally, the

speaes oi Myoxanthus form a unit recognizably distinct from the great masses

m Pleurothallis. Unless one is familiar with the species, these subtle differ¬

ences will not be appreciated. All the species are characterized by a well-

developed ramicaul that is usually borne by a short rhizome, but occasionally

repent and occasionaUy prolific habits are seen. The sheaths of the ramicauls

especially the lowermost sheaths, are scurfy in the majority of species. The

mtegument bears more or less transverse, variously formed appendages of

^ceUular trichomes that give the sheaths a pubescent or shaggy appearance

(Figure 1.).

As presently conceived, the shaggy sheaths of the ramicauls are not a posi¬

tive diagnostic criterion. The sheaths of the ramicauls of some unrelated taxa

{Pleurothallis snhgtnns Acianthera section Tomentosae, Restrepiopsis reichen-

bachiana and some species of Stelis) are also invested with trichomes. Three

species attributed to Myoxanthus (P. hirtipes, P. scabripes and P. spilantha)

have been discovered to belong to section Tomentosae of Pleurothallis The

speaes of subgenera Satyria (except for M. pan) and Silenia have sheaths that

rhp Irl/'lirtmoc

5 mm

5 of a sheath of s

SYSTEMATICS OF MYOXANTHUS

Myoxanthus subgenus Myoxanthus

Type: Myoxanthus monophyllus Poepp. & Endl.

This subgenus contains the majority of the species. It is subdivided into

three sections: one with a scandent or prolific habit, and two with a repent or

caespitose, non-prolific habit. The latter two sections are divided by the inflo¬

rescence: one that produces single flowers successively, and the other that

produces a few to many single flowers simultaneously in a fascicle.

Myoxanthus section Antennella Luer, sect. nov.

s Rcichb. f. = Myoxanthus ceratothaUis (Reichb. f.) Lucr.

rring to the usually prominent apices of the

Inflorcscentia pauciflora floribus successivis.

The ramicauls of this section are produced from a rhizome that varies

from being very short to produce a caespitose habit, to elongate to produce a

shortly repent or a long-repent habit. The flowers are produced successively,

one, two or sometimes three at a time. The apices of the petals are commonly

thickened or clavate.

Myoxanthus section Myoxanthus

& Endl.

The ramicauls of this section are produced from a rhizome that varies

from being very short to produce a caespitose habit, to elongate to produce a

shortly repent habit. A few to many flowers are produced simultaneously in a

congested fascicle.

Myoxanthus section Scandentia Luer, sect. nov.

Type: Pleurothallis scandens Ames = Myoxanthus scandens (Ames) Luer.

Ety.: From the Latin scandens, “climbing,” referring to the habit.

This section contains the seven scandent species of the genus that produce

the ramicauls from the apex of the preceding ramicaul instead of a rhizome.

The lowermost ramicaul produces the roots and it is usually much longer than

the upper ramicauls. The shorter, upper ramicauls are often produced in fasci¬

cles of a few to many from the apex of a lower ramicaul.

Myoxanthus subgenus Satyria Luer, subgen. nov.

Type: Pleurothallis pan Luer = Myoxanthus pan (Luer) Luer.

Ety.: From the Latin satyrus, “a satyr, a woodland deity,” in allusion to the fancied appear¬

ance of the flowers.

This subgenus is characterized by a single-flowered inflorescence that is

always borne laterally either from low on the ramicaul or from the rhizome.

The anther-cap is ciliate on the upper margin as seen in subgenus Myoxanthus.

This subgenus contains four species: M. balaeniceps and M. lappiformis with

the tip of the dorsal sepal held by the synsepal, and M. pan and M. stonei with

the tip of the dorsal sepal free.

ICONES PLEUROTHALLIDINARUM

Myoxanthus subgenus Silenia Luer, subgen. nov.

Type: Pleurothallis aspasicensis Reichb. f. = Myoxanthus aspasicensis (Reichb. f.) Luer.

From the Latin silenus, “an old, woodland deity,” in allusion to the fancied appearance

This subgenus is characterized by a single-flowered inflorescence that is

always borne terminally from the ramicaul at the conduplicate base of the leaf.

The flowers are fleshy and densely short-pubescent externally with the hairs

produced in clumps. The anther-cap is ciliate on the upper margin as in

Myoxanthus. Three species are included: M. aspasicensis, M. sempergemmatus

and M. uncinatus.

SPECIES ATTRIBUTED TO MYOXANTHUS

and list of illustrations

Myoxanthus afTinis (Lindley) Luer...

Myoxanthus affinoides Luer.

Myoxanthus aspasicensis (Reichb. L) Luer....l

Myoxanthus balaeniceps (Luer & Dressier) Luer

m^lhmbeyHcm (Reichb. f.) Luer = Pleurolhaiiirsiiiirip;^'

Myoxanthus ceratothalius (Reichb. f.) Luer ^

Myoxanthus chloe (Luer & V^quez) Luer .

Myoxanthus cimex Luer & Escobar....

...Plate 1.

.... Plate 2.

.... Plate 3.

.. Plate 45.

... Plate 41.

....Plate 4.

....Plate 5.

....Plate 6.

asstfsa s s.asKKtiKKBfe s a ssk.ecsps!" "

ICONES PLEUROTHALLIDINARUM

KEY TO THE SUBGENERA 0¥ MYOXANTHUS

1 Sheaths of the ramicauls scurfy; flowers produced laterally,

singly, successively or simultaneously from near the apex

of the ramicaul. Myoxanthus

V Sheaths of the ramicauls not scurfy (except Af. pan)\

flowers produced from low on the ramicaul, the rhizome,

or terminally at the base of the leaf.2

2 Flowers produced laterally, singly from low on the ramicaul

or the rhizome. Satyria

2’ Flowers produced terminally, singly, successively or simultaneously

from the base of the leaf. Silenia

KEY TO THE SECTIONS AND SPECIES

OF SUBGENUS MYOXANTHUS

1 Habit caespitose or repent. 2

r Habit scandent, the ramicaul proliferating other ramicauls 34

2^ Few to many flowers produced simultaneously 3

2’ Howers produced singly and successively (occasionaiiy 2 or 3

flowers are present simultaneously). 15

Section Myoxanthus

3 Habit shortly but distinctly repent, 0.5 to 1 or more cm

between ramicauls. ., i tu •

3 Habit very shortly repent to caespitose ^ ^

1 inflated, enclosing the base of the seoals s

4 Floral bract not enclosing the base of the sepals .6

7 Sepals about 5 mm long; petals oblone

T Sepals about 10 mm long; petals narrowed aSie the m^^^

8 Sepals about 5 mm wide; sepals and netak n

striped in purple.. * ^ prommently

8’ Sepals less than mm'iide; s^i^ and petals

not prommently Striped.. ^ ^

’ »p-

9- Up with the apex dilated; »tomn Sow liiiir of

SYSTEMATICS OF MYOXANTHUS

11 Lip with the margins fimbriate, more or less straight..

11’ Lip with the margins minutely erose, more or less

obtusely angled near the middle.

13 Sepals less than 4 mm long; lip with a verrucose callus

extending from the base to the apex. M. pulvinatus

13’ Sepals more than 6 mm long; lip without a verrucose callus

extending from the base to the apex.14

14 Sepals about twice as long as broad; lip with the sides

obtusely angled below the middle, the disc smooth. M. octomerioides

14’ Sepals more than twice as long as broad; lip with the sides

not angled, the disc more or less minutely verrucose. M. octomeriae

Section Antennella

17’ Petals thickened but not clavate..

.....M. mellitanthus

23 Sepals, petals and lip verrucose, the sepals more

than 25 cm long.

23’ Sepals, petals and lip not verrucose, the sepals less

than 2 cm long.

..M. serripetalus

.24

ICONES PLEUROTHALLIDINARUM

24 Lip subquadrate, long-dliate. hirsuticaulis

24’ Lip not subquadrate, long-ciliate.25

25 Sepals glabrous externally, or with sparse hairs.

25’ Sepals pubescent externally.

Lip convex at the broad apex, without lateral lobes..

Lip not convex at the apex, with lateral lobes.

Petals longer than the sepals, with slender apices....

Petals not longer than the sepals.

28 Leaves narrowly ovate, 1.5-2 cm wide;

lip subpandurate-trilobed.

28’ leaves narrowly terete, less than 0.5 cm wide;

lip subquadrate-trilobed.

29 Lip with low, indistinct, lateral lobes.

29’ Lip with broad, erect, lateral lobes.

30 Leaf more than 1 cm wde; petals narrowed

above the middle.

30’ Leaf less than 1 cm wide; petals narrowed

above the basal third.

Z'ZZ31

M. uxorius

.27

.28

.29

.M. eumeces

\f. antennifer

. M. merae

.30

...M. georgei

. M. ephelis

1], with uncinate, lateral lobes. M. ceratothallis

31 Leaf less than 1.5 cm wide; lip without uncinate lateral lobes.32

32 Lip minutely denticulate, with low, <

below the middle.

32’ Lip not denticulate, with small tri'j

near the middle, the margins not c

Section Scandentia

M Roral bract inflated, enclosing the base of the cu

34 Floral bract not enclosing the base of the coroUa

35 Rainiwuls produced singly; leaves up to 3 cm wide;

^tals far surpassing the sepals m length

35’ One to many ramicauls produced byTraik^'uirieaves i

more than 1.5 cm wide; petals not surpassing the sepals.,

“

36 Habit slender, pendent; sepals less than 9 n

37 Petals long-ciliate-fimbriate.

37 Petals neither ciliate nor fimbriate

,.35

,.37

. M. gyas

.36

M.frutex

.. M.chloe

■^.M. fimbriatus

.38

SYSTEMATICS OF MYOXAN'niUS

38 Lip thick, suborbicular, without lateral lobesA/. parvilabius

38’ Lip oblong-subpandurate, with lateral lobes.39

39 Leaves less than 5 mm wide; lip with low, uncinate

lateral lobes. M. scandens

39’ Leaves 8-11 mm wide; lip with tall, broad, uncinate

lateral lobes. M. epibator

KEY TO THE SPECIES OF SUBGENUS SATYRIA

1 Dorsal sepal subacute to obtuse, free from the lateral sepals.2

1’ Dorsal sepal narrowly acute, the tip held by the lateral sepals.3

2 Sheaths of the ramicauls pubescent; lip with a narrow, horse

shoe-shaped callus above the base. -M. pan

T Sheaths of the ramicauls glabrous; lip with a broad,

smooth callus above the base. M. stonei

3 Sepals less than 2 cm long; lip with a low, transversely

rugose callus above the base. M. lappiformis

3’ Sepals more than 3 cm long; lip with a tall, longitudinal

callus above the base. M. balaeniceps

KEY TO THE SPECIES OF SUBGENUS SILENIA

1 Flowers not cleistogamous; lip obtuse.2

1’ Flowers cleistogamous; Up acute. M. sempergemmatus

2 Flowers produced singly; Up with a broad, smooth

caUus above the base. M. uncinatus

2’ Flowers produced singly, often more than one at a

time; Up with a narrow, horse shoe-shaped caUus

above the base.-Af- aspasicensis

ICONES PLEUROTHALLIDINARUM

Figure 1 Afyoxantfms pan, Endres 315,

rere probably in Rcichcnbach’s

It AMES from W for about 37 w

n by A Endres together

1 for 20 years before his

J by Endres around

C. Luer ct^al., Hwered in cultivation 30 Mar. m\,^C. 667^ (SEL). Prov. o^ichincha^ oW

za, alt. 850 m, 3 Feb. 1987, C Luer, J.Luer&A. Him 12611 (MO).

SYSTEMATICS OF MYOXANTHUS

Plate 1. Myaxanthus ajfmis (Lindley) Luer

SYSTEMATICS OF MYOXANTHUS

Plate 2.

SYSTEMATICS OF MYOXANTHUS

Plate 4. Myoxanthus ceratothallus (Reichb. f.) Luer

SYSTEMATICS OF MYOXANTHUS

Plate 5. Myoxanthus chloe (Luer &. V^isquez) Luer

SYSTEMATICS OF MYOXANTHUS

Plate 6. Myoxanthus cimex Luer & Escobar

ICONES PLEUROTHALLIDINARUM

SYSTEMATICS OF MYOXANTHUS

Plate 7. Myoxanthus colothrix (Luer) Luer

SYSTEMATICS OF MYOXANTHUS

L

SYSTEMATICS OF MYOXANTHUS

Plate 10. Myoxanthus epibator Luer & Escobar

SYSTEMATICS OF MYOXANTHUS

L

ICONES PLEUROTHALLIDINARUM

SYSTEMATICS OF MYOXANTHUS

Plate 12. Myoxanthus exasperatus (Lindley) Luer

SYSTEMATICS OF MYOXANTHUS

39

SYSTEMATICS OF MYOXANTHUS

Plate 14. Myoxanthus frutex (Schltr.) Luer

SYSTEMATICS OF MYOXAOTHUS

Plate 15. Myoxanthus georgei (Luer) Luer

SYSTEMATICS OF MYOXANTIIUS

ii

SYSTEMATICS OF MYOXANTHUS

Plate 18. Myoxanthus hirsuticaulis (Ames & Schweinf.) Luer

SYSTEMATICS OF MYOXANTHUS

Plate 19. Myoxanthiis hystrix (Reichb. f.) Luer

ICONES PLEUROTHALLIDINARUM

SYSTEMATICS OF MYOXANTHUS

Plate 20. Myoxanthus lonchophyllus (Barb. Rodr.) Luer

54

SYSTEMATICS OF MYOXANTHUS

r

SYSTEMATICS OF MYOXANTHUS

57

SYSTEMATICS OF MYOXANTHUS

Plate 23. Myoxanthus merae (Luer) Luer

SYSTEMATICS OF MYOXANTHUS

Plate 25. Myoxanthus neillii Luer & Dodson

SYSTEMATICS OF MYOXANTHUS

SYSTEMATICS OF MYOXAMHUS

Plate 27. Myoxanthus octomerioides (Lindley)

PLEUROTHALLIDINARUM

SYSTEMATICS OF MYOXANTHUS

Plate 29. Myoxanthus priapus Luer

SYSTEMATICS OF MYOXANTHUS

ffffir

SYSTEMATICS OF MYOXANTHUS

Plate 31. Myoxanthus pmctatus (Barb. Rodr.) Luer

SYSTEMATICS OF MYOXANTHUS

Plate 32. Myoxanthus reymondii (Karst.) Luer

SYSTEMATICS OF MYOXAISTTHUS

Plate 33. Myoxanthus sarcodactylae (Luer)

SYSTEMATICS OF MYOXANTHUS

Plate 35. Myoxanthus serripetalus (Krzl-) Luer

SYSTTEMATICS OF MYOXArmiUS

PLEUROTOALLIDINARUM

SYSTEMATICS OF MYOXANTHUS

I

SYSTTEMATICS OF MYOXANTHUS

ICONES PLEUROTHALLIDINARUM

This species is relatively frequent and widely distributed from Central

America through the Andes into Amazonian Brazil adjacent to Peru. It is

recognized by the long-creeping rhizome with ascending ramicauls with usual¬

ly longer, narrow leaves. The single flowers are produced intermittently.

Most distinctive is the oblong lip with a short, sharp lobe on either side near

the middle, and a large, thick, obtuse, retrorse callus at the base.

Myoxanthus uxorius (Luer) Luer, Selbyana 7: 51,1982.

^s.: PleuroOmllisj^ria Luer, Selbyana 5:186,1979.

species. ’ ° iscovere t is

ECUADOR: Prov. of Zamora-Chinchipe:

epiphytic in cloud forest east of the pass be-

t^n Loja and Zamora, alt. 2500 m, 11 Feb.

/• ^ ^

^TJs^EL); along^hj; new road between Loja

Mar. 1984, C. Luer, S. Dalstrom, T. Hdijer. J.

& D. D'Alessandro 9624 (MO). Prov. of

V. Flores

O A , -—low m, Jan. 1989,

5 Dalstrom & T. Hdijer 1213 (MO). Prov of

Napo: above Baeza, alt. 1900 m. Mar. 1984 A

Him 1694 (MO).

COLOMBIA: Dept, of Antioquia: El Retiro

above Colomborqui'deas, collected bv w’

Teague, flowered in cultivation in &n Franck'

CO, W. Teague s.n. (MO).

This species occurs frequently in

the mountains of southeastern Ecua¬

dor. Vegetatively it is distinct in the t

terete above the middle. The pyriform lip is arcuate.

petals i

Plate 39. Myoxanthus wcorius (Luer)

i7:51,

SYSTEMATICS OF MYOXANTHUS

Plate 41. Myoxa

anthus balaeniceps (Luer & Dressle"

SYSTEMATICS OF MYOXANTHUS

Plate 42. Myoxamhm lappifomis (Heller & L.O.Wms.) Lucr

SYSTEMATICS OF MYOXANTHUS

Plate 43. Myoxanthus pan (Luer) Luer

SYSTEMATICS OF MYOXANTIIUS

101

Plate 44. Myoxanthus stonei (Luer) Luer

102

ICONES PLEUROTHALLIDINARUM

SYSTEMATICS OF MYOXANTHUS

103

SYSTEMATICS OF MYOXA^aHUS

105

Plate 46. Myoxanlhm sempergemmatus (Luer) I

PLEUROTHALLIDINARUM

SYSTEMATICS OF MYOXANTHUS

Plate 47. Myoxanthus uncinatus (Fawc.) Luer

am mm i

SYSTEMATICS OF MYOXANTHUS

109

amnoides6,9.I6,Plate2.

antennifer 1,6,10,18, Plalc 3.

aspasicensis6,7,ll,98,IOO,Platc45.,

beyrichii 6

ce.alothallis5,6,7,10,20,Plate4.,22,76

chloe 6,10,22, Plate 5.

cimex 6,9,24, Plate 6„ 50,56

colothrix 7,8,26, Plate 7,

dasyllis 7,9,16,28, Plate &

epIbMOT^!*! ll’, 30, Plate 10., 32,80

eumeces 7,10,32, Plate 11.

exasperates 7,8,14, 26,34,36, Plate 12.,

1,2,3,4,6,8,58

i-oxanthus 1,5,6,8

tyiia 1,2,3,4,6,8

enia 1,2, 4,6,8

ineUa 1,5,9

anthus 1,5,8,86,92

lenlia 1,5,10

no

SYSTEMATICS OF MYOXANTHUS

111

(Pleurothallis)

sempergemmata 104

serripetala 82

simplicicaulis 84

speciosa 86

spilantha 2, 7

stonei 98

(Pleurothallis)

uxoria 90

warmingii 52

Restrepiopsis reichenbachiana 2

Restrepia lonchophylla 1,52

“roezlii” 96

Reymondia 4

Solanaceae 1

Stelis 2

112

ICONES PLEUROTHALLIDINARUM

ADDENDA TO PLATYSTELE, PLEUROTHALLIS

SUBGENUS SCOPULA AND SCAPHOSEPALUM

SYSTEMATICS OF PLATYSTELE

113

Plate 77. Platystele dalstroemii Luer

114

SYSTEMATICS OF PLATYSTELE

115

Plate 78. Platystele jamoboeensis Luer & Hirtz

116

ICONES PLEUROTHALLIDINARUM

Plate 79. Platystele napintzae Luer & Hirtz

117

118

ICONES PLEUROTHALLIDINARUM

Plate 80. Platystele psix Luer & Hirtz

r

SYSTEMATICS OF PLATYSTELE

119

Plate 81. Platystele sulcata

Luer & Hirtz

SYSTEMATICS OF SCOPULA

121

Plate 7. Pleurothallis cosmetron Luer

SYSTEMATICS OF SCOPULA

123

Plate 8. Pleurothallis silverstonei Luer

SYSTEMAnCS OF SCAPHOSEPALUM

125

Plate 47. Scaphosepalum parviflorum Luer & Hirtz

VAir

SYSTEMATICS OF SCAPHOSEPALUM

127

Plate 48. Scaphosepalum pleurothallodes Luer & Hirtz

PLEUROTHALLIDINARUM