















  UNIVERSITY OF KANSAS PUBLICATIONS

  MUSEUM OF NATURAL HISTORY

  Volume 17, No. 13, pp. 559-578, 3 pls. 17-19

  Date, April 5, 1968


  Descriptions of New Hylid Frogs
  From México and Central America

  BY

  WILLIAM E. DUELLMAN


  UNIVERSITY OF KANSAS
  LAWRENCE
  1968

  UNIVERSITY OF KANSAS PUBLICATIONS, MUSEUM OF NATURAL HISTORY

  Editors: E. Raymond Hall, Chairman, Henry S. Fitch,
  Frank B. Cross

  Volume 17, No. 13, pp. 559-578, 3 pls. 17-19
  Published April 5, 1968

  UNIVERSITY OF KANSAS
  Lawrence, Kansas

  PRINTED BY
  ROBERT R. (BOB) SANDERS, STATE PRINTER
  TOPEKA, KANSAS

  1968

  31-9420


  Descriptions of New Hylid Frogs
  From México and Central America

  BY
  WILLIAM E. DUELLMAN


Biological exploration of México and Central America has revealed the
presence of a diverse fauna, elements of which have undergone speciation
in separate areas within the relatively small region. Some genera of
amphibians, especially _Eleutherodactylus_ and _Hyla_, are represented
by many species having small geographic ranges in México and Central
America. Most of the species of _Hyla_ inhabiting the lowlands have been
known to science for many years, and most of the novelties today are
found in the less accessible highlands. No fewer than 19 new species of
hylid frogs have been discovered and named from México and Central
America in the past decade.

In the spring and summer of 1966 I studied hylid frogs in many parts of
southern México and Central America; the field work was designed to
obtain specimens and data that would resolve certain systematic
problems. To a certain extent the studies were successful, but in the
course of the work five previously unknown hylids were discovered; these
are named and described in this paper. The only species described herein
that I do not know in life is one of _Plectrohyla_ that has been
represented in museum collections for several years but was not obtained
in my own field work.

In this paper I am presenting diagnoses, descriptions, and brief
comments on the relationships of five new species and one subspecies.
More exhaustive accounts will be included in a monograph, now in
preparation, on the Middle American hylids.

For use of comparative material used in the preparation of this paper, I
am indebted to Richard J. Baldauf, Texas Cooperative Wildlife Collection
(TCWC); Charles M. Bogert, American Museum of Natural History (AMNH);
James A. Peters, United States National Museum (USNM); Hobart M. Smith,
University of Illinois Museum of Natural History (UIMNH); Charles F.
Walker, University of Michigan Museum of Zoology (UMMZ); and Ernest E.
Williams, Museum of Comparative Zoology (MCZ). KU refers to the
University of Kansas Museum of Natural History. I am especially grateful
for help in obtaining specimens and data to Linda Trueb, who accompanied
me throughout México and Central America, where we were joined by John
D. Lynch in Costa Rica and Charles W. Myers in Panamá. Linda Trueb
offered helpful suggestions in the course of preparing the manuscript,
and David M. Dennis skillfully prepared the illustrations which more
accurately depict the frogs than my written descriptions; both of these
persons have my thanks for their contributions.

Ratibor Hartmann of Finca Santa Clara, Chiriquí, Panamá, made possible
our travels to the Río Changena on the Atlantic slopes of Bocas del
Toro. Field work in Costa Rica was facilitated by the Organization of
Tropical Studies through the courtesy of Stephen B. Preston and Norman
Scott. Rodolfo Hernandez Corzo of the Dirección General de la Fauna
Silvestre provided the necessary permits to collect in México. I thank
each of these persons for his helpfulness and cooperation.

Field work in México and Central America and the associated laboratory
studies on Middle American hylid frogs are supported by grants from the
National Science Foundation (GB-1441 and GB-5818). The field work in
Panamá was part of a survey of the herpetofauna of that country carried
out in cooperation with the Gorgas Memorial Laboratory and supported by
the National Institutes of Health (GM-12020).


Hyla xanthosticta new species

Plate 17

_Holotype._--Adult female, KU 103772, from the south fork of the Río Las
Vueltas on the south slope of Volcán Barba, near the northwest base of
Cerro Chompipe, Heredia Province, Costa Rica, elevation 2100 meters;
obtained on June 26, 1966, by John D. Lynch.

_Diagnosis._--A member of the _Hyla pictipes_ group (Starrett, 1966),
characterized by having dorsum uniform green, canthal stripe
bronze-color, flanks and anterior and posterior surfaces of thighs dark
brown with bright yellow spots, throat and belly yellow, and hands
having only vestigial web.

_Description of holotype._--Female having a snout-vent length of 29.3
mm.; tibia length 16.2 mm., 55.3 per cent of snout-vent length; foot
length (measured from proximal edge of inner metatarsal tubercle to tip
of longest toe) 14.1 mm., 48.1 per cent of snout-vent length; head
length 10.0 mm., 34.1 per cent of snout-vent length; head width 10.3
mm., 35.2 per cent of snout-vent length. Snout in lateral profile
truncate, slightly inclined posteroventrally, in dorsal profile narrow
but truncate; canthus angular; loreal region barely concave; lips thick,
barely flared. Snout long; distance from anterior corner of eye to
nostril equal to diameter of eye; nostrils slightly protuberant,
directed laterally; internarial distance, 2.6 mm.; internarial area
slightly depressed; top of head slightly convex; interorbital distance
3.2 mm., 31.1 per cent of width of head; width at eyelid 2.6 mm.; 24.3
per cent of width of head. Diameter of eye 3.0 mm.; thin dermal fold
extending posteriorly from posterior corner of eye, above tympanum, to
point above insertion of arm. Tympanum distinct, its diameter half that
of eye.

Axillary membrane absent; arms slender; thin scalloped dermal fold on
ventrolateral edge of forearm; thin dermal fold on wrist; fingers long,
tapering; length of fingers from shortest to longest, 1-2-4-3; discs
small, only slightly wider than digits; subarticular tubercles large;
distal tubercle on third finger broad, flat; distal tubercle on fourth
finger strongly bifid; supernumerary tubercles large, round, closely
spaced irregularly on proximal segments of digits; prepollex moderately
enlarged. Web lacking between first and second fingers, vestigial
between second and third fingers, extending from middle of
antepenultimate phalanx of third to base of penultimate phalanx of
fourth. Heels overlap by about one-third length of shank when hind limbs
adpressed; tibiotarsal articulation extends to anterior edge of eye;
thin transverse dermal fold on heel; scalloped dermal fold along outer
edge of tarsus; inner metatarsal tubercle large, flat, elliptical,
visible from above; toes long, slender; length of toes from longest to
shortest, 1-2-5-3-4; discs small, barely wider than digits; subarticular
tubercles large, round, subconical; supernumerary tubercles few,
scattered on proximal segments of digits; toes about two-thirds webbed;
webbing extending from middle of penultimate phalanx of first toe to
middle of penultimate phalanx of second, from distal end of penultimate
phalanx of second to base of penultimate of third, from distal end of
penultimate phalanx of third to middle of antepenultimate of fourth to
middle of penultimate of fifth toe.

Anal opening directed posteroventrally at level of mid-thigh, bordered
below by large tubercles; anal sheath lacking. Skin smooth on dorsum
except for small scattered tubercles, granular on belly and
posteroventral surfaces of thighs. Tongue round, emarginate, barely free
behind. Prevomerine teeth 5-5, on large ovoid elevations at level of
posterior edges of small round choanae.

Color (in preservative): dark purplish brown above, brown on limbs;
first three fingers and first three toes creamy yellow; other digits
brown; flanks dark brown with white spots; anterior and posterior
surfaces of thighs and inner surfaces of shanks brown with cream-colored
spots. White stripes on edge of upper lip, ventrolateral edge of
forearm, outer edge of tarsus, and above anus. Chin and throat white;
belly and ventral surfaces of limbs cream-color.

Color (in life): dorsum green, palest on sides of head; dorsal surfaces
of thighs tan; canthal stripe bronze-tan (reddish copper at night);
flanks, anterior and posterior surfaces of thighs, and inner surfaces of
tarsi brown with bright yellow spots. Throat and belly pale yellow;
ventral surfaces of limbs dull, dark yellow; large, bright yellow spot
on anteroventral surface of thigh; bright yellow tubercles on median
part of ventral surface of thigh. Anal area dark brown with white stripe
above and yellow stripe below; white stripe on outer edge of forearm,
outer edge of tarsus, and edge of upper lip. Iris gold-color with fine
black reticulations and faint reddish suffusion medially; palpebral
membrane clear.

_Comparisons._--_Hyla xanthosticta_ is a member of the _Hyla pictipes_
group that contains _debilis_, _pictipes_, _rivularis_, and _tica_. From
all of these, _xanthosticta_ differs by having large yellow spots on the
flanks and thighs, a white labial stripe, and a large yellow spot on the
proximal ventral surface of each thigh. Females of _Hyla pictipes_ have
small creamy yellow spots on the flanks and thighs but have dark spots
on the venter; furthermore, _pictipes_ lacks white stripes on the upper
lip and above the anus, lacks a canthal stripe, and has larger discs and
less webbing on the hand. _Hyla tica_ differs from _xanthosticta_ by
having white mottling on the flanks, dark transverse bands on the limbs,
and larger discs, and lacks yellow spots on the thighs, and white
stripes on the upper lip, limbs, and above the anus. _Hyla rivularis_ is
notably different in having a tan dorsum and creamy yellow venter with
black flecks; moreover, _rivularis_ lacks spots on the flanks and thighs
and white stripes on the upper lip, limbs, and above the anus. Of all of
the species in the _pictipes_ group, _xanthosticta_ most closely
resembles _debilis_. This species has a dull green dorsum, usually
flecked with brown or black, and a creamy white venter. The flanks of
_debilis_ are creamy white with small brown flecks, and the anterior and
posterior surfaces of the thighs are bright yellow. _Hyla debilis_ has a
dull tan canthal stripe and white spots on the upper lip; the webbing on
the hand is slightly more extensive, and the discs are slightly larger,
in _debilis_ than in _xanthosticta_.

The presence of the large yellow spots on the flanks and thighs in
combination with the uniformly green dorsum and yellow venter
immediately distinguishes _Hyla xanthosticta_ from all other known
species of Middle American hylids.

_Remarks._--The only known specimen of _Hyla xanthosticta_ was perched
at night on a leaf about one meter above the ground. The frog was found
in humid upper montane forest characterized by large oaks supporting
many bromeliads and heavy growths of mosses. Two other members of the
_Hyla pictipes_ group--_pictipes_ and _rivularis_--were abundant along a
stream in the oak forest.

The specific name is derived from the Greek _xanthos_ meaning yellow and
the Greek _stiktos_ meaning spotted, and alludes to the diagnostic
yellow spots on the flanks and thighs.


Hyla pseudopuma infucata new subspecies

Plate 17

_Holotype._--Adult male, KU 101770 from the Río Changena, Bocas del Toro
Province, Panamá, elevation 830 meters; obtained May 18, 1966, by
William E. Duellman.

_Paratypes._--KU 101771-80; MCZ 55251-2, and UMMZ 126811-12, same
locality; collected May 18-22, 1966, by William E. Duellman.

_Diagnosis._--A subspecies of _Hyla pseudopuma_ characterized by having
dark red, instead of yellow, in groin and on anterior and posterior
surfaces of thighs; white stripe above anal opening; and blunt snout.

_Description of holotype._--Adult male having a snout-vent length of
37.8 mm.; tibia length 20.6 mm., 54.4 per cent of snout-vent length;
foot length (measured from proximal edge of inner metatarsal tubercle)
18.6 mm., 49.2 per cent of snout-vent length; head length 11.9 mm., 31.4
per cent of snout-vent length; head width 11.4 mm., 30.1 per cent of
snout-vent length. Snout in lateral profile bluntly rounded, in dorsal
profile truncate; canthus rounded; loreal region barely concave; lips
thick, moderately flared. Snout short, distance from anterior corner of
eye to nostril equal to about three-fourths diameter of eye; nostrils
slightly protuberant, directed dorsolaterally; internarial distance 2.6
mm.; internarial area not depressed; top of head flat; interorbital
distance 3.8 mm., 33.3 per cent of width of head; width of eyelid 3.2
mm., 28.2 per cent of width of head. Eye large, protuberant, diameter
4.3 mm.; thin dermal fold extending posteriorly from posterior corner of
eye, obscuring upper edge of tympanum, curving downward to point above
insertion of arm. Tympanum distinct except dorsally, its diameter 51.1
per cent that of eye, separated from eye by distance equal to diameter
of tympanum.

Axillary membrane absent; arms moderately robust; dermal fold on outer
edge of forearm indistinct, interrupted; transverse fold on wrist weak;
fingers short, stocky; length of fingers from shortest to longest,
1-2-4-3; discs large, width of that on third finger 2.6 mm., larger than
tympanum; subarticular tubercles moderately small, flat, none distinctly
bifid; supernumerary tubercles conical, present on proximal segments;
prepollex enlarged, bearing nuptial excrescence composed of many minute
horny spinules; webbing absent between first and second fingers,
extending from middle of antepenultimate phalanx of second to base of
antepenultimate phalanx of third and beyond to base of penultimate
phalanx of fourth finger. Heels overlap by about one-third length of
tarsus when hind limbs adpressed; tibiotarsal articulation extends to
anterior corner of eye; transverse dermal fold on heel; tarsal fold
absent; inner metatarsal tubercle long, elliptical, flat, barely visible
from above; outer metatarsal tubercle small, conical; toes moderately
long, stout; length of toes from shortest to longest, 1-2-3-5-4; discs
nearly as large as those on fingers; subarticular tubercles small, flat;
supernumerary tubercles large, conical, pigmented, in single row on
proximal segments of each toe; toes about two-thirds webbed; webbing
extending from distal end of penultimate phalanx of first toe to base of
penultimate phalanx of second, from distal end of penultimate phalanx of
second to middle of antepenultimate of third, from distal end of
penultimate phalanx of third to base of penultimate of fourth to distal
end of penultimate of fifth toe.

Anal opening directed posteriorly at level of upper surfaces of thighs,
bordered below by vertical flesh folds; anal sheath absent. Skin of
belly, ventral surfaces of arms, and proximal posteroventral surfaces of
thighs granular, elsewhere smooth. Tongue ovoid, about twice as long as
wide, shallowly notched posteriorly, barely free behind. Prevomerine
teeth 5-6, situated on transverse ridges between posterior borders of
small round choanae. Vocal slit extending from midlateral edge of tongue
to angle of jaw.

Color (in preservative): dorsum grayish tan with large brown blotch
extending from eyelids to middle of back, limbs marked with brown
transverse bars, 2 on each forearm, 3 on each thigh, shank, and foot.
Flanks dark gray with white spots; groin, anterior and posterior
surfaces of thighs, ventral surfaces of shanks, and inner edges of feet
orange-tan; anal region dark brown, bordered above by white stripe;
belly and chin creamy white, latter with grayish brown flecks.

Color (in life): dorsum yellowish tan with olive-brown markings by night
and uniform pale yellowish tan by day; axilla, inner surface of elbow,
groin, anterior and posterior surfaces of thighs, ventral surfaces of
thighs and shanks, inner surfaces of feet, and dorsal surfaces of first
three toes tomato red; flanks dark blue with yellow spots and
reticulations. Throat, chest, and anterior part of belly creamy white;
posterior part of belly orange, becoming red in extreme posterior
region; throat flecked with brown; iris pale bronze with black
reticulations; palpebral membrane clear above, yellowish tan below;
nuptial excrescenses dark brown.

_Variation._--The discussion of variation is based on the type series
plus 31 specimens (KU 101781-811) from the Río Claro near its junction
with the Río Changena, at an elevation of 910 meters. Females are
slightly larger than males, but do not differ significantly in
proportions (Table 1). All specimens have the diagnostic red legs and
blue flanks with yellow spots or mottling, but the dorsal pattern is
highly variable. In most individuals the dark markings on the dorsum are
a solid color, but in some the borders of the marks are dark, and the
interior of each mark is nearly the same color as the rest of the
dorsum. A triangular dark mark with the anterolateral corners on the
eyelids is present in all specimens. In some individuals the posteriorly
directed apex of this triangular mark is connected to the apex of
another triangular mark on the back; in other individuals the marks are
narrowly separated, whereas in a few specimens the marks are broadly
connected. A dark blotch usually is present on the posterior end of the
body. One specimen (KU 101771) has many small white spots on the dorsum.
The white stripe above the anus is invariably present, and the
transverse bars on the limbs are present in all specimens, although they
are indistinct in some individuals. The pattern on the flanks varies
from three or four large spots to many (30-44) small spots. All males
have dark flecks or reticulations on the throat; in some individuals the
chest and belly are heavily flecked. Although the amount of flecking is
much less in most females, one individual is as heavily flecked on the
throat and belly as any male.

The change in coloration in this frog is noteworthy. The following
description of metachrosis in seven specimens from the Río Claro
illustrates the change. At night the frogs were yellowish tan above with
slightly darker dorsal markings. The axilla, groin, anterior and
posterior surfaces of the thighs, ventral surfaces of the hind limbs,
and webbing on the hands and feet were tomato red. By day, some
individuals became creamy yellow, others ashy white, and others grayish
tan. The flanks were dark blue with yellow spots.

_Comparisons._--The population of frogs described here closely resembles
_Hyla pseudopuma_ Günther in the highlands of Costa Rica. Both have the
same kind of, and variation in, dorsal markings; conical, pigmented
supernumerary tubercles on the toes; bilobate vocal sac; and large
prepollex bearing horny nuptial spinules. Although at present no
evidence for intergradation exists, the population described here is
considered to be a subspecies of _Hyla pseudopuma_.

The two subspecies exhibit few differences in size and proportions,
except that the tympanum is larger in _pseudopuma_ (Table 1). _Hyla p.
pseudopuma_ has dark brown or yellowish tan thighs and brown flanks with
a few creamy white spots; the groin in some specimens is pale blue. The
red color on the limbs characteristic of _infucata_ is lacking in
_pseudopuma_, which also lacks the white stripe above the anus
characteristic of _infucata_. The only noticeable morphological
difference between the subspecies, except in the size of the tympanum,
is the shape of the snout. In _infucata_ the snout is bluntly rounded in
lateral profile and truncate in dorsal profile, whereas in _pseudopuma_
the snout is more acutely rounded in lateral profile and acuminate in
dorsal profile (Fig. 1). This external difference is correlated with the
nature of the underlying premaxillaries. In _infucata_ the
premaxillaries lie in a transverse plane and have short, nearly vertical
alary processes, whereas in _pseudopuma_ the premaxillaries lie at a
slight angle and have longer alary processes that are inclined
posteriorly.

TABLE 1.--Variation in Certain Measurements and Proportions in the
Subspecies of Hyla pseudopuma. (Means Are Given in Parentheses Below the
Observed Range.)

==================+========+==+==========+==========+==========+==========
                  |        |  |Snout-vent|   Tibia  |   Foot   | Tympanum/
SUBSPECIES        |   Sex  | N|  length  |  length/ |  length/ |    eye
                  |        |  |          |   S-V L  |   S-V L  |
------------------+--------+--+----------+----------+----------+----------
_H. p. pseudopuma_|[Male]  |31| 37.6-41.4| 48.5-55.0| 44.7-52.9| 47.6-66.7
                  |[symbol]|  |  (39.7)  |  (51.5)  |  (48.2)  |  (57.6)
                  |        |  |          |          |          |
_H. p. infucata_  |[Male]  |31| 37.6-42.9| 50.7-56.9| 43.3-49.5| 41.8-55.3
                  |[symbol]|  |  (39.5)  |  (53.4)  |  (47.4)  |  (49.2)
                  |        |  |          |          |          |
_H. p. pseudopuma_|[Female]|11| 41.6-47.6| 49.1-53.8| 45.4-49.5| 57.9-71.4
                  |[symbol]|  |  (44.3)  |  (51.7)  |  (47.6)  |  (60.2)
                  |        |  |          |          |          |
_H. p. infucata_  |[Female]|11| 41.1-45.6| 50.0-55.4| 43.5-47.4| 47.6-56.1
                  |[symbol]|  |  (42.6)  |  (52.6)  |  (45.8)  |  (50.1)
------------------+--------+--+----------+----------+----------+----------

[Illustration: FIG. 1. Lateral views of the heads of _Hyla pseudopuma
pseudopuma_ (left, KU 64884) and _H. p. infucata_ (right, KU 101784). ×
4.]

The only other frog in Central America having red webs and anterior and
posterior surfaces of the thighs is _Hyla loquax_, which has a broad
head, extensive axillary membrane, single median vocal sac, and
uniformly creamy yellow flanks; furthermore, _loquax_ lacks conical,
pigmented supernumerary tubercles on the toes and a large prepollex with
horny nuptial spinules. _Hyla rufitela_ has red webbing, but in no
other diagnostic feature resembles _infucata_, for _rufitela_ is green
above, white below, and has angular prevomerine dentigerous ridges.

_Remarks._--Most specimens of _Hyla pseudopuma infucata_ were found on
bushes and low trees at night. Three males and one clasping pair were on
the ground. The habitat is humid lower montane forest where the amount
of rainfall is high. Although no breeding was observed nor calls heard,
it is presumed that this subspecies breeds in shallow, temporary pools,
like those utilized by the nominate subspecies.

The two localities where _Hyla pseudopuma infucata_ is known are in the
maze of ridges north of Cerro Pando on the Panamanian-Costa Rican
border. The Río Claro is a tributary of the Río Changena, in turn a
tributary of the Río Changuinola, which receives many streams and rivers
draining the northern slopes of the highlands in Bocas del Toro Province
before flowing into the Caribbean. We reached the Río Claro and Río
Changena by walking from Finca Santa Clara on the Pacific slopes, over
the continental divide, and down the north slope of Cerro Pando.

The subspecific name is derived from the Latin _infucatus_, meaning
painted, in allusion to the red colors on the limbs and webs.


Hyla pellita new species

Plate 18

_Holotype._--Adult male, KU 100970 from 33 kilometers north of San
Gabriel Mixtepec, Oaxaca, México, elevation 1675 meters; obtained on
February 20, 1966, by William E. Duellman and Linda Trueb.

_Paratypes._--KU 100971-2 collected with the holotype and KU 100974-5
from 30 kilometers north of San Gabriel Mixtepec, Oaxaca, México,
elevation 1530 meters; same date and collectors.

_Diagnosis._--A small yellowish tan _Hyla_ characterized by tympanum
concealed, anal opening not bordered below by large tubercles, brown
bands on shanks, and dark flecks on roof of mouth anteriorly.

_Description of holotype._--Adult male having snout-vent length of 27.3
mm.; tibia length 13.7 mm., 50.2 per cent of snout-vent length; foot
length (measured from proximal edge of inner metatarsal tubercle to tip
of longest toe) 11.7 mm., 42.9 per cent of snout-vent length; head
length 8.7 mm., 31.9 per cent of snout-vent length. Snout in lateral
profile truncate, rounded above, in dorsal profile rounded; canthus
angular; loreal region slightly concave; lips thin, flared. Snout
moderately long, distance from anterior corner of eye to nostril
slightly less than diameter of eye; nostrils slightly protuberant,
directed anterolaterally; internarial area barely depressed; distance
between nostrils 2.6 mm.; top of head flat; interorbital distance 3.2
mm., 34.4 per cent of width of head. Diameter of eye 2.7 mm.; thin
dermal fold extending from posterior corner of eye to point above
insertion of arm; tympanum absent, not visible through skin.

Axillary membrane absent; forearms moderately slender, having indistinct
tuberculate fold on ventrolateral edge, lacking distinct transverse fold
on wrist; fingers short; length of fingers from shortest to longest,
1-4-2-3, fourth nearly as long as second; discs small, about half again
as wide as digits; subarticular tubercules large, round, flattened,
distal ones on third and fourth fingers bifid; supernumerary tubercles
large, round, present only on proximal segments; prepollex barely
enlarged, lacking nuptial excrecence. Web lacking between first and
second fingers, extending from base of penultimate phalanx of second to
base of antepenultimate phalanx of third, from middle of antepenultimate
phalanx of third to distal end of antepenultimate of fourth finger.
Heels overlap by about one-fifth length of shank when hind limbs
adpressed; tibiotarsal articulation extending to middle of eye, tarsal
fold present, extending full length of tarsus; inner metatarsal tubercle
flat, ovoid, partly visible from above; outer metatarsal tubercle
absent; toes short; length of toes from shortest to longest, 1-2-3-5-4;
discs small, about two-thirds width of those on fingers; subarticular
tubercles small, round; supernumerary tubercles small, flattened,
irregularly arranged on proximal segments. Toes three-fourth webbed; web
extending from base of disc of first to middle of penultimate phalanx of
second, from base of disc of second to middle of penultimate phalanx of
third, from base of disc of third to base of penultimate phalanx of
fourth and to base of disc of fifth toe.

Anal opening directed posteriorly at level of dorsal surfaces of thighs,
bordered below by vertical dermal folds and few small tubercles; anal
sheath absent. Skin heavily granular on throat, chest, belly and ventral
surfaces of thighs, smooth elsewhere. Tongue cordiform, deeply notched
posteriorly, barely free behind. Prevomerine teeth 3-4, situated on
short elevations between small round choanae; vocal slits absent.

Color (in preservative): pale tan above with dark brown mark in
occipital region and large irregular brown mark extending from scapular
region to sacral region; anterior and posterior surfaces of thighs and
flanks lacking pigment; dorsal surfaces of arms, shanks, and feet tan
with brown transverse bars (two on each forearm, two on left shank, one
on right shank, and one on each foot); entire dorsal surfaces, except
hands and first four toes, peppered with black; venter creamy white;
roof of mouth between, and anterior to, choanae speckled with minute
black flecks.

Color (in life): yellowish tan above with reddish brown flecks (later
changed to pale brown with dull olive-green interorbital bar, blotch on
back, and flecks on dorsum); hands, feet, and anterior and posterior
surfaces of thighs dull yellow; belly white; creamy white stripes on
outer edge of forearm, foot, and above anus; iris pale silver-bronze.

_Variation._--Three adult males (including holotype) have snout-vent
lengths of 25.2-27.3 (mean 26.5) mm., and two females have 28.6 and 31.6
(mean 30.1) mm. One juvenile has a snout-vent length of 21.5 mm. No
significant variation occurs in the proportions. Males have 6-8, and
females have 8 and 9, prevomerine teeth. The tympanum is completely
concealed in all specimens.

All specimens have distinct transverse bars on the limbs; the number of
bars on the shank varies from one to four. Two individuals are dark
brown dorsally; in these the small black flecks either are not visible
or are absent; flecks are present on the dorsal surfaces of four
specimens that are tan or pale brown above with darker brown irregular
markings.

The coloration in life consisted of olive-green or olive-brown markings
on the body and olive-green or brown bars on the limbs. The dorsal
ground color was yellowish tan or pale brown in all individuals.

_Comparisons._--_Hyla pellita_ differs from all known Middle American
_Hyla_, except _mixe_, _mixomaculata_, _nubicola_, and _pinorum_, by
having a concealed tympanum. The first three of these differ from
_pellita_ in greater size and by having many bands on the hind limbs.
Superficially _H. pellita_ resembles _Hyla pinorum_, which likewise
has a tan dorsum with irregular markings and limbs with transverse bars.
_Hyla pinorum_ differs from _pellita_ by having a proportionately larger
head, no transverse bands on the thighs, and large tubercles below the
anus. Furthermore, in _pinorum_ the quadratojugal articulates with the
maxillary, whereas in _pellita_ the quadratojugal is reduced to a small
spur and does not articulate with the maxillary.

_Remarks._--All individuals were found on low vegetation along streams
in cloud forest at night. No specimens were found when the type locality
was revisited in August, 1966.

Duellman (1960) placed _Hyla pinorum_ Taylor in the synonymy of
_Ptychohyla leonhardschultzei_ Ahl. At that time only the holotype, a
female, of _H. pinorum_ was known. In 1964 Kraig Adler and I
independently collected frogs and associated tadpoles in Guerrero that
subsequently proved to be _Hyla pinorum_ and provided evidence that
_Hyla pinorum_ is not conspecific with _Ptychohyla leonhardschultzei_.

The specific name _pellita_ is Latin, meaning covered with skin, and is
here used in reference to the complete concealment of the tympanum
beneath the skin.


Hyla siopela new species

Plate 18

_Holotype._--Adult male, KU 100981, from a small stream on the west
slope of Cofre de Perote, Veracruz, México, elevation 2500-2550 meters;
obtained on July 30, 1966, by William E. Duellman.

_Paratypes._--KU 100976-80, 100982-5, same locality, date, and
collector; KU 105628-9, same locality, obtained on June 18, 1966, by
Howard L. Freeman; UIMNH 57687-57701, same locality, obtained on July
30-31, 1964, by Macreay J. Landy and John D. Lynch.

_Diagnosis._--A member of the _Hyla bistincta_ group characterized by
truncate snout with short rostral keel; fingers having little webbing
and bearing large discs; axillary membrane absent; thoracic fold weak;
prepollex large, flat, bearing small nuptial spines; vocal slits absent;
dorsum green or tan with small irregular dark spots; flanks mottled.

_Description of holotype._--Adult male having a snout-vent length of
44.3 mm.; tibia length 21.1 mm., 47.6 per cent of snout-vent length;
foot length (measured from proximal edge of inner metatarsal tubercle to
tip of longest toe) 20.4 mm., 47.2 per cent of snout-vent length; head
length 13.4 mm., 30.2 per cent of snout-vent length; head width 13.7
mm., 30.9 per cent of snout-vent length. Snout in lateral profile
truncate, in dorsal profile truncate with weak vertical rostral keel;
canthus angular; loreal region slightly concave; lips thick, not
flaring; snout short; nostrils barely protuberant, directed
dorsolaterally, situated about four-fifths distance from anterior corner
of eye to tip of snout; internarial distance 3.6 mm.; internarial area
not depressed; top of head slightly convex; interorbital distance 4.9
mm., 35.8 per cent of width of head; width of eyelid 3.5 mm., 26.0 per
cent of width of head. Diameter of eye 4.7 mm.; heavy dermal fold
curving posteroventrally from posterior corner of eye, covering upper
one-third of tympanum, to insertion of arm; tympanum barely distinct,
its diameter 2.2 mm., 46.8 per cent that of eye, separated from eye by
distance equal to half again diameter of tympanum.

Axillary membrane absent; thoracic fold weak; arms moderately robust;
fold on wrist heavy; fingers long, slender; length of fingers from
shortest to longest, 1-2-4-3; discs large, that on third finger as large
as tympanum; subarticular tubercles moderately small, round, none bifid;
supernumerary tubercles small, some barely distinguishable, in single
row on proximal segment of each digit; prepollex greatly enlarged, flat
ventrally, bearing nuptial excrescence composed of minute horny
spinules; webbing between first two fingers vestigial; web connecting
other fingers at bases of penultimate phalanges of second and fourth,
and base of antepenultimate phalanx of third fingers. Heels overlap by
about one-third length of shank when hind limbs adpressed; tibiotarsal
articulation extends to posterior edge of orbit; transverse dermal fold
on heel; tarsal fold thin, distinct, extending length of tarsus; inner
metatarsal tubercle large, elongate, flat, visible from above; outer
metatarsal tubercle absent; toes moderately long, slender; length of
toes from shortest to longest, 1-2-3-5-4; discs slightly smaller than
those on fingers; subarticular tubercles moderately small, round;
supernumerary tubercles small, in single row on proximal segment of each
digit; toes about two-thirds webbed; webbing extends from middle of
penultimate phalanx of first toe to base of penultimate phalanx of
second, from middle of penultimate of second to middle of
antepenultimate of third, from middle of penultimate of third to middle
of antepenultimate of fourth to middle of penultimate phalanx of fifth
toe.

Anal opening directed posteriorly at level of mid-thigh; anal sheath
short. Skin granular on chin, belly, and posteroventral surfaces of
thighs, smooth elsewhere. Tongue broadly cordiform, notched posteriorly,
barely free behind. Prevomerine teeth 4-4, situated on posteromedially
inclined elevations between small ovoid choanae. Vocal slits absent.

Color (in preservative): dull grayish brown above with small,
irregularly-shaped black spots on head, back, and limbs; flanks gray
mottled with creamy tan; anterior and posterior surfaces of thighs tan;
belly dull creamy tan; throat marked with gray blotches; anal region and
posterodorsal surfaces of thighs marked with small white spots.

Color (in life): dorsum pale green with black spots and reticulations;
flanks mottled dark brown and creamy white; outer edges of feet silvery
white with brown spots; anterior and posterior surfaces of thighs dull
brown; webbing and first three toes dull yellowish tan; belly creamy
gray; throat silvery white, mottled with gray; iris dull bronze-color
with black reticulations; palpebral membrane clear.

_Variation._--The snout-vent length in seven adult males is 47.2-50.0
mm., and in five females, 45.1-52.5 mm. In neither sex do the average
proportions differ noticeably from those of the holotype, except that
the tympanum is relatively larger in females. The ratio of the diameter
of the tympanum to that of the eye is 0.363-0.468 (mean 0.438) in males
and 0.500-0.545 (mean 0.516) in females. The average number of
prevomerine teeth in males is 7.9, in females 8.4.

In life dorsal coloration varied from pale green to olive-green with
darker green or black flecks or reticulations, or pinkish tan to brown
with dark brown flecks or reticulations. Some preserved specimens have
relatively few dark flecks, whereas in most specimens the dorsum is
heavily marked. All specimens have some white markings above the anus
and on the posterodorsal surfaces of the thighs, but in some individuals
the white flecks are expanded and interconnected forming an irregular
white line.

Juveniles have a notably different coloration in life. The dorsum is
uniform pale green; the anterior and posterior surfaces of the thighs,
fingers, first three toes, and webbing are deep yellow. The anal stripe
is creamy white, and the flanks are pale gray with black flecks. The
upper lip, supratympanic fold, and canthal stripe are a bronze color.
The belly is pale yellow with a silvery cast on the throat. Juveniles
having snout-vent lengths from 24.5 to 36.6 mm. are so colored in life,
and uniform dark bluish gray dorsally in preservative.

_Comparisons._--The absence of a quadratojugal and the presence of a
greatly enlarged, non-projecting prepollex place _Hyla siopela_ in the
_Hyla bistincta_ group (see Duellman, 1964, and Adler, 1965). The
presence of a rostral keel separates _Hyla siopela_ from other members
of the _Hyla bistincta_ group, which is composed of two species having
long anal sheaths (_bistincta_ and _pentheter_), two small species
having axillary membranes and lacking nuptial excrescences in breeding
males (_charadricola_ and _chryses_), and three species (_crassa_,
_pachyderma_, and _robertsorum_) having short heads, round snouts, short
anal sheaths, and nuptial excrescences in breeding males. _Hyla siopela_
differs from the last three species in the shape of the snout and from
each in certain structural features; _H. crassa_ has fully webbed feet;
_H. pachyderma_ has large nuptial spines, and _H. robertsorum_ has more
webbing and a shorter tarsal fold. Furthermore, the venter in _H.
robertsorum_ is brown with creamy white flecks.

In structure and coloration _H. arborescandens_ resembles _siopela_, but
the former is smaller, and males of _arborescandens_ have vocal slits.

_Remarks._--This description brings to eight the number of species now
recognized in the _Hyla bistincta_ group. _Hyla siopela_ is most closely
related to _Hyla robertsorum_ from the high mountains of the Sierra
Madre Oriental in northern Puebla and eastern Hidalgo. Possibly the four
species now recognized in the _crassa_ subgroup (_crassa_, _pachyderma_,
_robertsorum_, and _siopela_) are only subspecies of a single species,
but differences in the amount of webbing in _crassa_ and the nature of
the nuptial excrescenses in _pachyderma_ indicate that they are distinct
species.

The type locality of _Hyla siopela_ is a small stream cascading down the
western slope of Cofre de Perote; the lower reaches of the stream can be
reached by a dirt road leading east from the village of Perote for about
2 kilometers to a small park. The frogs were found in the stream at
elevations of 50 to 100 meters higher than the park. The stream flows
through a ravine supporting open, dry pine forest. Although the stream
was searched thoroughly in February, 1966, no frogs were found. In July,
1966, adults and juveniles were found in crevices and under overhanging
rocks behind small cascades and waterfalls by day and sitting on rocks
and branches in the spray of cascades at night.

The specific name _siopela_ is derived from the Greek _siopelos_,
meaning silent, and alludes to the absence of a voice in this species.


Hyla altipotens new species

Plate 19

_Holotype._--Adult male, KU 101001, from 37 kilometers (by road) north
of San Gabriel Mixtepec (kilometer post 183 on road from Oaxaca to
Puerto Escondido), Oaxaca, México, elevation 1860 meters; obtained on
February 19, 1966, by William E. Duellman.

_Paratypes._--KU 101002-6 collected at the same locality on February 19
and 20, 1966, by William E. Duellman, and KU 101008 from 33 kilometers
(by road) north of San Gabriel Mixtepec, Oaxaca, México, elevation 1675
meters; obtained on February 20, 1966, by Linda Trueb.

_Diagnosis._--A member of the _Hyla taeniopus_ group characterized by a
yellow venter, yellow flecks on posterior surfaces of thighs,
bronze-colored stripe from snout, along canthus and edge of upper eyelid
to point above arm, pointed snout, smooth dorsum, and no sexual
dimorphism in shape of snout.

_Description of holotype._--Adult male having a snout-vent length of
68.8 mm.; tibia length 36.2 mm., 52.6 per cent of snout-vent length;
foot length (measured from proximal edge of inner metatarsal tubercle)
31.1 mm., 45.2 per cent of snout-vent length; head length 20.2 mm., 29.4
per cent of snout-vent length; head width 20.0 mm., 29.1 per cent of
snout-vent length. Snout in lateral profile acutely rounded, protruding
beyond tip of lower jaw, in dorsal profile pointed; canthus angular;
loreal region flat; lips thick, barely flared. Snout long; nostrils
slightly protuberant, directed dorsolaterally, situated about two-thirds
distance from anterior corner of eye to tip of snout; internarial
distance 5.6 mm.; internarial area slightly depressed; top of head flat;
interorbital distance 6.0 mm., 30.0 per cent of width of head; width of
eyelid 4.7 mm., 23.5 per cent of width of head. Diameter of eye 6.2 mm.;
heavy dermal fold extending from posterior corner of eye, over upper
edge of tympanum to point above insertion of arm; tympanum distinct, its
diameter 3.4 mm., 54.8 per cent of that of the eye, separated from eye
by distance equal to diameter of tympanum.

Axillary membrane absent; arms moderately robust, lacking dermal fold on
lateral edge of forearm, having transverse fold on wrist; fingers
moderately short, broad; length of fingers from shortest to longest,
1-2-4-3; discs large, that on third finger one-fourth larger than
tympanum; subarticular tubercles large, round, none bifid; supernumerary
tubercles large, granule-like, present only on proximal segments;
prepollex enlarged, not bearing nuptial excrescence. Fingers about
one-half webbed; webbing connects first and second fingers at level of
distal end of antepenultimate phalanx, extending from middle of
penultimate phalanx of second finger to middle of antepenultimate
phalanx of third, and between bases of penultimate phalanges of third
and fourth fingers. Heels overlap by about one-half length of shank when
hind limbs adpressed; tibiotarsal articulation extends to point between
eye and nostril; thin transverse dermal fold on heel; tarsal fold
strong, extending full length of tarsus; inner metatarsal tubercle
small, flat, elongate, barely visible from above; outer metatarsal
tubercle small, conical; toes moderately long, stout; length of toes
from shortest to longest, 1-2-3-5-4; discs slightly smaller than those
on fingers; subarticular tubercles large, round, subconical;
supernumerary tubercles large, conical, in single row on proximal
segment of each digit; toes about four-fifths webbed; webbing extending
from base of disc on first to base of disc on second to base of
penultimate phalanx of third toe, from base of disc on third to base of
penultimate phalanx of fourth to base of disc of fifth toe.

Anal opening directed posteroventrally at mid-level of thighs; anal
sheath long, tubular.  Skin smooth on dorsum and on ventral surfaces of
shanks, granular on throat, belly, and ventral surfaces of arms and
thighs. Tongue ovoid, widest posteriorly, neither notched nor free
behind. Prevomerine teeth 6-7, situated on robust transverse ridges
between small, ovoid choanae. Vocal slits absent. Testes large, ovoid,
granular; length of left testis 11.0 mm.

Color (in preservative): brown above with many darker brown spots and
narrow middorsal stripe on back; six or seven dark brown transverse bars
on each segment of hind limbs and four bars on each forearm; flanks
white with dark brown spots; anterior surfaces of thighs creamy white
with brown reticulations; posterior surfaces of thighs dark brown with
creamy yellow flecks; stripe on snout, canthus, edge of upper eyelid,
and supratympanic fold tan; ventral surfaces of feet brown; rest of
venter creamy white; stripe above anus white.

Color (in life): green above with slightly darker green spots; dorsal
surfaces of upper arms and thighs tan with green transverse bars; upper
surfaces of forearms and shanks green with darker green transverse bars;
feet, fourth and fifth toes, and third and fourth fingers tan with brown
transverse bars; other fingers and toes tan with brown flecks. Ventral
surfaces creamy yellow, brightest on throat and chest; flanks and
anterior surfaces of thighs bright creamy yellow with dark brown
reticulations and spots; posterior surfaces of thighs and ventral
surfaces of feet dark brown with yellow flecks; ventral surfaces of
hands and webbing on hands and feet yellowish tan. Labial stripe tan;
stripes on outer edge of forearm, along outer edge of foot, and above
anus cream-color; stripe on canthus, edge of upper eyelid, and on
supratympanic fold bronze-color. Iris pale bronze with black
reticulations and faint median, horizontal copper-colored streak; pupil
horizontally elliptical with ventral notch; palpebral membrane clear
above, pale bluish green with brown reticulations below.

_Variation._--In life all individuals had creamy yellow venters and
yellow flanks and anterior surfaces of thighs with brown or black spots
and mottling. Most of the adults were colored like the holotype, but one
was a much darker olive-green, and one was uniform brown above with a
dark brown middorsal stripe. Most subadults (snout-vent lengths
31.6-50.1 mm.) were pale reddish tan above with darker reddish brown
bars on the limbs and blotches on the back. The side of the head was
dark brown and the stripe along the canthus, edge of upper eyelid, and
supratympanic fold was yellowish tan. Some individuals had a dark brown
middorsal stripe. The posterior surfaces of the thighs were dull
yellowish tan; yellow flecks were present in the larger individuals.

TABLE 2.--Variation in Measurements and Proportions in Hyla altipotens.
       (Means Are Given in Parentheses Below the Observed Range.)

=========+===+=============+=============+=============+=============
         |   |    Snout-   |    Tibia    |    Foot     | Tympanum/
  SEX    | N |     vent    |   length/   |   length/   |    eye
         |   |    length   |    S-V L    |    S-V L    |
---------+---+-------------+-------------+-------------+-------------
  Males  | 5 |  68.8-75.1  |  52.6-55.8  |  28.1-30.0  |  41.4-55.2
         |   |    (70.7)   |    (53.7)   |    (29.2)   |    (50.6)
         |   |             |             |             |
 Females | 2 |  69.4-75.3  |  55.8-56.2  |  28.8-31.1  |  53.3-63.0
         |   |    (72.4)   |    (56.0)   |    (29.9)   |    (58.8)
---------+---+-------------+-------------+-------------+-------------

The number of transverse bars on each thigh and shank varies from five
to eight. The white stripe above the anus and the stripe from the snout
along the side of the head are invariably present. In some of the
largest individuals the brown reticulations on the anterior surface of
the thigh extend onto the ventral surface; in these specimens brown
flecks are present on the ventral surfaces on the shanks.

The tympanum is proportionately larger in females than in males; the
variation in size and proportions is given in Table 2. The total number
of prevomerine teeth varies from 13 to 18 (mean, 15) in five adult males
and from 10 to 12 (mean 11) in two females.

The testes in all adult males are granular, ovoid in shape, and greatly
enlarged. The lengths of the left testis in each of the five males are
11.0 to 23.5 (mean 14.6) mm.

_Comparisons._--On the basis of external appearance and certain cranial
characters (large frontoparietal fontanelle, broad sphenethmoid, large
nasals broadly separated medially having thin lateral processes
articulating with the palatines, short squamosal not articulating with
the maxillary, and quadratojugal present and articulating with the
maxillary), _Hyla altipotens_ can be associated with the _Hyla
taeniopus_ group (Duellman, 1965, Lynch and Smith, 1966). _Hyla
altipotens_ can be distinguished from all of the other members of the
group by its narrow head, pointed snout in both sexes, and uniformly
yellow throat and belly.

Small brown individuals of _Hyla altipotens_ superficially resemble
adult _Hyla pinorum_. The latter species has a covered tympanum, less
webbing on the hands, and a short, blunt snout.

_Remarks._--This stream-breeding frog is like _Hyla taeniopus_ in having
greatly enlarged testes, which possibly through the production of vast
quantities of sperm are an adaptation for successful breeding in
torrential streams (Duellman, 1965:164).

All individuals were found in trees and bushes near streams in cloud
forest at night in February. The type locality is the same as that of
_Hyla pentheter_ and _Hyla thorectes_, discovered by Kraig Adler in
June, 1964. Our field work there in February, 1966, resulted in finding
_Hyla altipotens_, _H. pellita_, and _Ptychohyla leonhardschultzei_, but
no individuals of the species found by Adler. A visit to the same
locality in August, 1966, revealed no individuals of either _H.
altipotens_ or _pellita_; instead _pentheter_ and _thorectes_ were found
along the stream.

Duellman (1965:166) listed a specimen (TCWC 16184) of _Hyla chaneque_
from Los Fustes, 3 kilometers east of San Sebastian, Oaxaca.
Reëxamination of this specimen reveals that it is _Hyla altipotens_.
The frog was obtained by Dilford Carter on April 29, 1960; it was under
a rock at the edge of a stream in an oak-pine-cypress association at an
elevation of 1800 meters.

The specific name _altipotens_ is Latin, meaning mighty, here used in
allusion to the supposed potentiality of fertilization by the production
of vast quantities of sperm in the large testes.


Plectrohyla hartwegi new species

Plate 19

_Holotype._--Adult male, UMMZ 94428, from Barrejonel (19 kilometers west
of Chicomuselo), Chiapas, México, elevation 1000 meters, obtained on
June 12, 1941, by Eizi Matuda.

_Paratypes._--Two subadult males, KU 58873 from Parajé El Triunfo, north
of Mapastepec, Chiapas, México, elevation 2050 meters, obtained on May
12, 1960, by Miguel Alvarez del Toro, and UIMNH 40837 from Cerro Azul
Oaxaca, México, obtained on March 7, 1956, by Thomas MacDougall.

_Diagnosis._--A _Plectrohyla_ having a bifid prepollex, bold mottling on
flanks and ventral surfaces of shanks, and vertical dark bars on
anterior and posterior surfaces of thighs, and lacking vocal slits and
outer tarsal fold.

_Description of holotype._--Adult male having a snout-vent length of
63.8 mm.; tibia length 34.9 mm., 54.7 per cent of snout-vent length;
foot length (measured from proximal edge of inner metatarsal tubercle to
tip of longest toe) 31.1 mm., 48.7 per cent of snout-vent length; head
length 19.7 mm., 30.9 per cent of snout-vent length; head width 22.6
mm., 35.4 per cent of snout-vent length. Snout short, distance from
level of anterior edge of orbit to tip of snout 70.6 per cent of length
of eye; snout in lateral profile angular, sloping abruptly from nostrils
to jaw, in dorsal profile bluntly rounded, lacking rostral keel; canthal
ridge thickened; loreal region deeply concave; lips thick, barely
flared. Nostrils small, barely protuberant, directed anterolaterally,
situated about two-thirds distance from eye to tip of snout; internarial
distance 5.6 mm. internarial area barely depressed near convergence of
canthal ridges; top of head flat; interorbital distance 6.4 mm., 28.3
per cent of head width; diameter of eye 6.8 mm.; width of eyelid 5.5
mm., 24.3 per cent of head width. Heavy dermal fold extending
posteriorly from posterior edge of orbit, covering upper edge of
tympanum; two thinner folds extending ventrally from longitudinal heavy
fold covering posterior edge of tympanum; anterior and ventral edges of
tympanum distinct; length of tympanum 2.9 mm., 42.6 per cent of diameter
of eye.

Axillary membrane absent; arms robust, forearm not noticeably heavier
than upper arm; distinct transverse fold on wrist. Fingers long,
moderately slender; length of fingers from shortest to longest, 1-2-4-3;
discs moderately large, that on third finger larger than tympanum;
webbing vestigial; subarticular tubercles small, conical; terminal
tubercle on fourth finger somewhat flattened; supernumerary tubercles
small, in one row on proximal segment of fourth finger and in two rows
on proximal segments of other fingers; prepollex greatly enlarged,
barely bifurcate; spines not protruding through skin; distal spine much
longer than proximal one (Fig. 2). Heels overlap by about one-third
length of shank when hind limbs adpressed; tibiotarsal articulation
extends slightly beyond snout; heavy transverse dermal fold on heel;
inner tarsal fold heavy, extending full length of tarsus; outer tarsal
fold absent; inner metatarsal tubercle high, elliptical, visible from
above, outer metatarsal tubercle absent. Toes long, slender; length of
toes from shortest to longest, 1-2-5-3-4; fifth toe nearly as long as
third; discs small; subarticular tubercles small, round; supernumerary
tubercles small, in single row on proximal segment of each digit; toes
about three-fourths webbed; webbing extending from base of disc of first
toe to base of penultimate phalanx of third, from base of disc of third
to base of penultimate phalanx of fourth to base of disc of fifth toe.

[Illustration: FIG. 2. Palmar view of prepollical spine of right hand of
_Plectrohyla hartwegi_ (UMMZ 94428). × 5.]

Anal opening directed posteroventrally at level of mid-thigh; anal
sheath long with membranous connection to posterior surfaces of thighs.
Skin on dorsal surfaces finely tuberculate; that on throat, chest,
belly, and ventral surfaces of thighs granular, that on ventral surfaces
of arms and shanks smooth. Tongue nearly round, free posteriorly for
about one-fourth its length, barely notched behind. Upper jaw shallowly
notched medially. Maxillary-premaxillary teeth 38-35; prevomerine teeth
5-5, situated on small elliptical elevations between quadrangular
choanae; vocal slits absent.

Color (in preservative): uniform dull brown above and creamy yellow
below; flanks brown with creamy yellow mottling and dark brown spots in
groin; anterior surfaces of thighs creamy yellow with two broad,
vertical, dark brown bars proximally and two narrower, dull brown bars
distally; posterior surfaces of thighs brown with dark brown vertical
bars, interspaces cream-colored or brown. Ventral surfaces of shanks
creamy yellow with bold brown reticulations.

_Variation._--The paratypes are smaller, having snout-vent lengths of
48.3 and 41.8 mm. In these specimens the ratio of the length of the
tibia to the snout-vent length is 55.9 and 57.9 per cent, and the ratio
of the diameter of the tympanum to the diameter of the eye is 47.3 and
43.6 per cent, respectively. Both specimens have 4-4 prevomerine teeth;
one specimen has 37-36, and the other has 40-37, maxillary-premaxillary
teeth. In these small specimens the supratympanic fold is thin, and the
arms are not so robust as in the holotype. In one specimen (KU 58873)
the tongue is not notched posteriorly. The terminal subarticular
tubercle on each fourth finger is broad and flattened in UIMNH 40837,
but conical in KU 58873. Both specimens have bold creamy-yellow and dark
brown mottling on the flanks and dark brown reticulations on the ventral
surfaces of the shanks. There are two dark brown vertical bars on the
anterior and posterior surfaces of each thigh in KU 58873 and three bars
on each surface in UIMNH 40837.

_Comparisons._--_Plectrohyla hartwegi_ differs from all known species in
the genus by having boldly mottled flanks, dark reticulations on the
ventral surfaces of the shanks, and dark vertical bars on the shanks. In
all of the other species the anterior and posterior surfaces of the
thighs are unmarked, and the flanks are either plain or marked with
small spots or flecks. Structurally, _P. hartwegi_ belongs in the
_guatemalensis_ group of the genus, containing _avia_, _glandulosa_,
_guatemalensis_, and _pycnochila_. The species in this group lack vocal
slits and have either large, rectangular, or bifid prepollices.
_Plectrohyla hartwegi_ differs from all of these species, except
_pycnochila_, by having a tuberculate, instead of a smooth, dorsum, and
_hartwegi_ differs from _pycnochila_ by having a bifid, instead of a
rectangular, prepollex.

_Remarks._--The known distribution of _Plectrohyla hartwegi_ includes
three localities at elevations of 1000 to 2050 meters in the Sierra
Madre of Chiapas and extreme eastern Oaxaca. The specimen from Parajé El
Triunfo was found in a rocky stream in cloud forest at an elevation of
2050 meters. One _Plectrohyla sagorum_ was obtained from the same
stream.

Eizi Matuda sent the holotype to the late Dr. Norman Hartweg, who
recognized that the specimen was unique but was reluctant to name the
species on the basis of a single specimen. Now that two additional
specimens are available, it seems appropriate to associate Hartweg's
name with this new species of _Plectrohyla_, a genus that Hartweg first
adequately defined.


LITERATURE CITED

  ADLER, K.
   1965. Three new frogs of the genus _Hyla_ from the Sierra
   Madre del Sur of México. Occas. Papers Mus. Zool. Univ.
   Michigan, 642:1-18, pl. 1, December 16.

  DUELLMAN, W. E.
   1960. Synonymy, variation, and distribution of _Ptychohyla
   leonhardschultzei_ Ahl. Studies of American hylid frogs, IV.
   Herpetologica, 16:191-197, September 23.

   1964. A review of the frogs of the _Hyla bistincta_ group.
   Univ. Kansas Publ. Mus. Nat. Hist., 15:469-491, March 2.

   1965. Frogs of the _Hyla taeniopus_ group. Copeia,
   2:159-168, June 25.

  STARRETT, P.
   1966. Rediscovery of _Hyla pictipes_ Cope, with description
   of a new montane stream _Hyla_ from Costa Rica. Bull. South.
   California Acad. Sci., 65 (1):17-28, March.


 _Transmitted July 11, 1967._

[Illustration: PLATE 17
  Upper figure, _Hyla xanthosticta_ (KU 103772);
  lower figure, _Hyla pseudopuma infucata_ (KU 101770). × 2.]

[Illustration: PLATE 18
  Upper figure, _Hyla pellita_ (KU 100973);
  middle figure, _Hyla pellita_ (KU 100970);
  lower figure, _Hyla siopela_ (KU 100977). × 2.]

[Illustration: PLATE 19
  Upper figure, _Hyla altipotens_ (KU 101001);
  lower figure, _Plectrohyla hartwegi_ (UMMZ 94428). × 1.]

31-9420




Transcriber's Notes:

Obvious punctuation errors corrected.

Spelling corrections:
  'Mexico' to 'México' on title page for consistency.
  'granulelike' to 'granule-like'
     ...large, granule-like, present...
  'midlevel' to 'mid-level'
     ... at mid-level of thighs...
  'posterio' to 'posterior'
     ...anterior and posterior surfaces of thighs...
   'flank' to 'flanks'
   ...mottling on flanks...







