










UNIVERSITY OF KANSAS PUBLICATIONS MUSEUM OF NATURAL HISTORY

Volume 13, No. 8, Pl. 25, figs. 1-2, pp. 349-357 April 27, 1961


Descriptions of Two Species of Frogs, Genus Ptychohyla Studies of
American Hylid Frogs, V

BY WILLIAM E. DUELLMAN


UNIVERSITY OF KANSAS LAWRENCE 1961




UNIVERSITY OF KANSAS PUBLICATIONS, MUSEUM OF NATURAL HISTORY

Editors: E. Raymond Hall, Chairman, Henry S. Fitch,
Robert W. Wilson


Volume 13, No. 8, Pl. 25, figs. 1-2, pp. 349-357
Published April 27, 1961


UNIVERSITY OF KANSAS
Lawrence, Kansas


PRINTED IN
THE STATE PRINTING PLANT
TOPEKA, KANSAS
1961

28-6442




Descriptions of Two New Species of Frogs,
Genus Ptychohyla
Studies of American Hylid Frogs, V

BY

WILLIAM E. DUELLMAN


Field studies on hylid frogs in southern México and northern Central
America have resulted in the collection of numerous specimens of
_Ptychohyla_, a genus of hylid frogs heretofore poorly represented in
museum collections. Experience with the living frogs in their natural
habitats has been helpful in defining the species and in formulating
ideas concerning their relationships.

Taylor (1944) proposed the generic name _Ptychohyla_ for a new species
of frog, _Ptychohyla adipoventris_ [= _Ptychohyla leonhard-schultzei_
(Ahl)--_fide_ Duellman, 1960] from Agua del Obispo, Guerrero. Taylor
defined the genus as having large ventrolateral glands and horny
nuptial spines in males. Stuart (1954:169) discussed the generic
characters and pointed out that both the ventrolateral glands and horny
nuptial spines were seasonal in their development, being found only in
breeding males. Stuart then went on to describe _Ptychohyla
schmidtorum_, a species characterized by the absence of horny nuptial
spines in breeding males. My investigations of these frogs have
revealed the presence of two groups of species. In both groups breeding
males have large ventrolateral glands, but the two groups are easily
separated by four characters. The first group contains, among others,
_Ptychohyla leonhard-schultzei_, _euthysanota_, _spinipollex_, and
another species in the Mesa Central of Chiapas to which I tentatively
apply the name _Ptychohyla macrotympanum_ (Tanner), 1957. This group of
species is characterized by horny nuptial spines in breeding males,
presence of a tarsal fold, a call consisting of a single long note, and
tadpoles having lips not greatly expanded. The second group, as
recognized here, is characterized by the absence of horny nuptial
spines in breeding males, lack of a tarsal fold, a call consisting of a
series of short notes, and tadpoles having greatly expanded lips. In
this group belong _Ptychohyla schmidtorum_ and the two species
described below.

Only the descriptions of the new species are given in this paper;
detailed comparisons, descriptions of osteological features, analyses
of calls, and discussions of relationships are reserved for a
forthcoming review of the entire genus.

In the spring of 1959, collections of amphibians and reptiles were made
in the cloud forests on the northern slopes of the Sierra Madre
Oriental in northern Oaxaca. Among the hylids found, two specimens of a
heretofore unnamed species of _Ptychohyla_ have brilliant red
flash-colors on the groin and thighs; in allusion to these fiery colors
I propose that this species be named:

~_Ptychohyla ignicolor_~ new species

(Plate 25, Fig. 1)

     _Holotype._--University of Michigan Museum of Zoology No.
     119603, from a stream 6 kilometers south of Vista Hermosa,
     Oaxaca, México (1865 meters); obtained on March 31, 1959, by
     Thomas E. Moore. Original Number WED 14159.

     _Paratype._--UMMZ 119602 from Vista Hermosa, Oaxaca (1500
     meters); obtained on March 30, 1959, by William E. Duellman.

     _Diagnosis._--A species of the _schmidtorum_-group of
     _Ptychohyla_ differing from other known members of the group
     in having the diameter of the tympanum less than one-half
     the diameter of the eye, no white spot below the eye, no
     lateral light stripe, bright green dorsum in life and red
     flash-colors on groin and thighs.

     _Description of Holotype._--Adult male having a snout-vent
     length of 30.0 mm.; tibia length, 14.6 mm.; tibia
     length/snout-vent length, 48.7 per cent; foot length
     (measured from proximal edge of inner metatarsal tubercle to
     tip of longest toe), 12.3 mm.; head length, 9.2 mm.; head
     length/snout-vent length, 32.3 per cent; head width, 9.3
     mm.; head width/snout-vent length, 31.0 per cent; diameter
     of eye, 3.2 mm.; diameter of tympanum, 1.3 mm.;
     tympanum/eye, 40.6 per cent. Snout in lateral profile
     square, in dorsal profile obtusely rounded; canthus
     pronounced; loreal region slightly concave; lips moderately
     flaring; top of head flat; nostrils protuberant; internarial
     distance, 2.8 mm.; interorbital distance, 3.3 mm., much
     broader than width of eyelid, 2.8 mm. A heavy dermal fold
     from posterior corner of eye above tympanum to insertion of
     forelimb, covering upper edge of tympanum; tympanum
     elliptical, its greatest diameter equal to its distance from
     eye. Forearm robust with a distinct fold on wrist; pollex
     moderately enlarged without nuptial spines; second and
     fourth fingers equal in length; subarticular tubercles
     round; none is bifid; disc of third finger slightly larger
     than tympanum; no web between first and second fingers;
     vestige of web between other fingers. Heels overlap when
     hind limbs adpressed; tibiotarsal articulation extends to
     anterior corner of eye; no tarsal fold; inner metatarsal
     tubercle large, flat, and elliptical; outer metatarsal
     tubercle near inner one and triangular; subarticular
     tubercles round; length of digits from shortest to longest
     1-2-5-3-4; toes about one-half webbed; discs smaller on toes
     than on fingers. Anal opening directed posteriorly at upper
     level of thighs; no anal flap; pair of large tubercles below
     anal opening; small tubercles ventral and lateral to these.
     Skin of dorsum and ventral surfaces of limbs smooth, that of
     throat and belly granular. Ventrolateral glands noticeably
     thickened, extending from axilla nearly to groin and only
     narrowly separated medially on chest. Skin of anterior part
     of chin thickened and glandular. Tongue cordiform, shallowly
     notched behind and only slightly free posteriorly; vomerine
     teeth 0-3, situated on rounded elevations between somewhat
     larger, round inner nares; openings to vocal sac large, one
     situated along posterior margin of each mandibular ramus.

PLATE 25

[Illustration: FIG. 1. Paratype of _Ptychohyla ignicolor_
(UMMZ 119602). × 3.]

[Illustration: FIG. 2. Holotype of _Ptychohyla chamulae_
(KU 58063). × 3.]

     Color (in alcohol) dull brown above with irregular dark
     brown blotches; dorsal surfaces of limbs brown with narrow
     darker brown transverse bars; posterior surfaces of thighs
     cream-color with brown spots and mottling; groin and dorsal
     surfaces of first and second toes white; belly
     cream-colored; glandular areas orange-brown; chest and chin
     having black spots. Ventral surfaces of hind limbs and first
     toes cream-colored; undersides of other toes and soles of
     feet brown.

     Color (in life) uniform bright green above; venter pale
     creamy yellow; anterior and posterior surfaces of thighs,
     ventral surfaces of shanks, anterior surfaces of tarsi and
     upper proximal surfaces of first three toes red; iris pale
     golden color.

     The paratype is an adult male, having a snout-vent length of
     26.3 mm., and agrees with the holotype in proportions. The
     ventrolateral glands are less extensive and the chin less
     spotted than in the holotype.

     _Comparisons_: Both _Ptychohyla schmidtorum_ and the species
     described below differ from _P. ignicolor_ in lacking red
     flash-colors and in having a white spot below the eye.
     _Ptychohyla ignicolor_ also differs in having a small
     tympanum. As stated above, these species can be
     distinguished from the rest of the genus by the absence of a
     tarsal fold and absence of horny nuptial spines in breeding
     males.

     _Remarks_: The holotype was found on a moss-covered log over
     a stream in dense cloud forest by day. The paratype was
     calling at night from a low herb at the edge of a small
     stream in the cloud forest. Nearby a _Ptychohyla
     leonhard-schultzei_ was calling.

Along two cascading mountain streams in cloud forest on the northern
slopes of the Mesa Central in central Chiapas numerous specimens of a
distinctive species of _Ptychohyla_ were found in association with two
species of _Hyla_ and two of _Plectrohyla_. The first specimen of this
new species of _Ptychohyla_ was discovered by Dale L. Hoyt, who found
the frog on a rock at midday. At night on August 5, 1960, numerous
individuals were found calling from leaves of plants growing on the
slopes of the ravine by the streams. None was more than two meters
above the ground. Tadpoles were found in the fast-flowing stream, where
they were holding onto rocks with their mouths. Little is known of the
herpetofauna of these mountains that are the home of the Chamula
Indians. Since the little frog described here comes from the land of
the Chamulas, I propose that it be named:

~_Ptychohyla chamulae_~ new species

(Plate 25, Fig. 2)

     _Holotype._--University of Kansas Museum of Natural History
     No. 58063, from a stream above (6.2 kilometers by road
     south) Rayón Mescalapa, Chiapas, México (1690 meters); one
     of a series collected on August 5, 1960, by William E.
     Duellman, Dale L. Hoyt, and John Wellman. Original No. WED
     17327.

     _Paratypes._--KU Nos. 58064-58073 collected with the holotype.

     _Diagnosis._--A species of the _schmidtorum_-group of
     _Ptychohyla_ differing from other known members of the group
     in having the following combination of characters: diameter
     of tympanum not noticeably less than half that of eye; white
     spot below eye; white lateral stripe on body anteriorly;
     dorsum bright green in life; thighs yellowish brown.

     _Description of Holotype._--Adult male having snout-vent
     length of 27.3 mm.; tibia length, 12.8 mm.; tibia
     length/snout-vent length, 48.7 per cent; foot length
     (measured from proximal edge of inner metatarsal tubercle to
     tip of longest toe), 10.8 mm.; head length, 9.2 mm.; head
     length/snout-vent length, 33.7 per cent; head width, 9.0
     mm.; head width/snout-vent length, 30.9 per cent; diameter
     of eye, 2.8 mm.; diameter of tympanum, 1.4 mm.;
     tympanum/eye, 50.0 per cent. Snout in lateral profile nearly
     square, slightly rounded above; in dorsal profile bluntly
     squared; canthus pronounced; loreal region concave; lips
     thick, rounded, and flaring; nostrils protuberant;
     internarial distance, 2.3 mm.; top of head flat;
     interorbital distance, 3.3 mm.; much broader than width of
     eyelid, 2.4 mm. A thin dermal fold from posterior corner of
     eye above tympanum to insertion of forelimb, covering upper
     edge of tympanum; tympanum nearly round, its diameter equal
     to its distance from eye. Forearm slender lacking distinct
     fold on wrist; a row of low, rounded tubercles on
     ventrolateral surface of forearm; pollex moderately enlarged
     without nuptial spines; second and fourth fingers equal in
     length; subarticular tubercles round, none bifid; discs
     small, that of third finger noticeably smaller than
     tympanum; no web between first and second fingers; vestige
     of web between other fingers. Heels overlap when hind limbs
     adpressed; tibiotarsal articulation reaches to middle of
     eye; no tarsal fold; inner metatarsal tubercle large, flat,
     and elliptical; outer metatarsal tubercle slightly more
     distal than inner, small, and elliptical; subarticular
     tubercles round; length of digits from shortest to longest
     1-2-5-3-4; third and fifth toes webbed to base of disc;
     fourth toe webbed to base of penultimate phalanx; discs
     smaller on toes than on fingers. Anal opening directed
     posteriorly at upper level of thighs; no anal flap; pair of
     large tubercles below anal opening and a slightly smaller
     pair farther below. Skin of dorsum and ventral surfaces of
     forelimbs and shanks smooth; that of throat, belly, and
     ventral surfaces of thighs granular. Ventrolateral glands
     well developed, not reaching axilla or groin and broadly
     separated midventrally. Skin of anterior part of chin
     glandular. Tongue cordiform, shallowly notched behind and
     only slightly free posteriorly; vomerine teeth 2-2, situated
     on small triangular elevations between large, ovoid inner
     nares; openings to vocal sac large, one situated along inner
     posterior edge of each mandibular ramus.

     Color (in alcohol) dark purplish brown on dorsal surfaces of
     head, body, and shanks; thighs brown above and yellowish tan
     posteriorly; white stripe extending from below eye above
     forearm to mid-flank. Ventral surfaces creamy white;
     ventrolateral glands orange-tan flecked with dark brown;
     edge of lower lip with dark brown spots; narrow white line
     on upper lip; palms white and soles brown.

     Color (in life) uniform dark bright green above with creamy
     white bar below eye; lateral stripe silvery white; ventral
     surfaces deep yellow; posterior surfaces of thighs yellow
     brown; iris reddish bronze.

     _Variation._--Sixteen adult males are available; these have
     snout-vent lengths of 26.3 to 28.5 mm. (average, 27.6 mm.).
     The tympanum/eye ratio is 48.2 to 58.6 per cent (average,
     53.2 per cent). The number of vomerine teeth varies from
     four to six. The extent of the ventrolateral glands is
     variable. In five specimens the glands nearly meet
     midventrally; in two others the glands include the axillary
     region; in none do the glands extend into the groin. In
     other structural details there is no noticeable variation.

     The greatest variation in color pattern is found in the
     lateral stripe. The pale spot or bar below the eye is
     present in all specimens; in one individual there is no
     lateral stripe; in three the stripe extends posteriorly only
     to above the forearm, in two to the mid-flank, and in the
     others to the groin.

     Although all of the males were bright uniform green above
     when collected at night as they were calling, some changed
     color later. In these individuals the dorsum became a
     somewhat paler green with faint irregular yellowish tan
     blotches.

     The one available female (UMMZ 121399) has a snout-vent
     length of 30.3 mm. and a tympanum/eye ratio of 52.8 per
     cent, and is colored like the males. The tubercles by the
     anal opening are placed irregularly and do not consist of
     two pairs below the opening. There are no ventrolateral
     glands, glandular area on the chin, or enlarged prepollex.

     _Comparisons._--_Ptychohyla chamulae_ resembles _P.
     schmidtorum_ in color pattern and body proportions, but the
     ground color of _schmidtorum_ is chocolate brown and not
     green as in _chamulae_. Also, in _schmidtorum_ the webbing
     and posterior surfaces of the thighs are pale cream-color in
     preserved specimens as contrasted with tan in _chamulae_. In
     living _schmidtorum_ the iris is bright red, not reddish
     bronze as in _chamulae_. The ventrolateral glands in
     _schmidtorum_ more closely approximate one another
     midventrally than in _chamulae_. It is conceivable that
     these populations are subspecifically related; _schmidtorum_
     occurs in the same kind of habitat as does _chamulae_, but
     is known only from the Pacific slopes of southeastern
     Chiapas and southwestern Guatemala, whereas _chamulae_ is
     known only from the Atlantic slopes of the Mesa Central in
     north-central Chiapas. Both of these species differ from
     _Ptychohyla ignicolor_ in having a relatively larger
     tympanum, more webbing on the foot, different arrangement of
     anal tubercles, and different coloration.

     _Description of Tadpole._--Six tadpoles having fully
     developed mouth parts have body lengths of 5.5 to 11.9 mm.
     and total lengths of 17.3 to 44.0 mm. The following
     description is based on a tadpole (KU 58199) having small
     hind limbs, a body length of 10.5 mm., and a total length of
     39.0 mm. Body ovoid, only slightly flattened dorsally and
     ventrally (Fig. 1); body only slightly deeper than wide;
     eyes directed dorsolaterally and slightly protuberant;
     nostrils small. Tail long and slender; greatest depth of
     tail-musculature two-thirds greatest depth of tail-fin;
     tail-musculature extending nearly to tip of tail-fin.

     Mouth directed anteroventrally; thin fleshy lips greatly
     expanded and forming large suckerlike disc; width of mouth
     greater than width of snout and nearly as wide as body.
     Outer edge of lips having small papillae; inner surface of
     mouth smooth; scattered large papillae, seemingly in rows,
     around teeth and beak (Fig. 2). Tooth rows 3/3; the upper
     rows subequal in length; upper rows one and three
     interrupted medially; lower rows one and two about equal in
     length to upper rows; third lower row short. Upper beak
     heavy and horn-covered.

[Illustration: FIG. 1. Tadpole of _Ptychohyla chamulae_
(KU 58199). × 2.5.]

[Illustration: FIG. 2. Mouthparts of tadpole of _Ptychohyla chamulae_
(KU 58199). × 16.]

     Color (in alcohol) dark brown over entire body and
     tail-musculature; a white area near base of tail, and a dark
     streak on anterior one-fourth of tail; tail-fin transparent
     having brown blotches.

     _Remarks_.--Five metamorphosing tadpoles and juveniles (KU
     58074, 58234-8) were found at night on vegetation by
     streams. Of two completely metamorphosed young each has a
     snout-vent length of 15.7 mm. Another having a snout-vent
     length of 16.2 mm. has a tail stub 2 mm. long and a
     completely metamorphosed mouth. Two others have snout-vent
     lengths of 13.6 and 14.1 mm. and tail lengths of 11.5 and
     8.1 mm. respectively; in these the mouth parts are
     incompletely metamorphosed. The single female available
     (UMMZ 121399) contains approximately 60 ovarian eggs, the
     largest of which are about 2.5 mm. in diameter.

     _Referred Specimens.--Chiapas_: 6.2 km. S of Rayón
     Mescalapa, KU 58063-74, 58199 (1 tadpole), 58234-8; 5.6 km.
     S of Rayón Mescalapa, KU 58062, 58200 (5 tadpoles); 11.4 mi.
     N of Pueblo Nuevo Solistahuacán, UMMZ 121395-9. The
     specimens listed last were collected along a stream between
     Pueblo Nuevo Solistahuacán and Rayón Mescalapa, which,
     according to Floyd L. Downs, is probably the same stream
     listed above as 5.6 km. S of Rayón Mescalapa.

Acknowledgments

I take this opportunity to thank Dale L. Hoyt, Thomas E. Moore, and
John Wellman, who ably assisted in collecting and studying these frogs
in the field. I am indebted to Floyd L. Downs for permission to include
specimens collected by him and John Winklemann. My studies on hylid
frogs are supported by the National Science Foundation (Grant G 9827).


LITERATURE CITED


DUELLMAN, W. E.

     1960. Synonymy, variation, and distribution of _Ptychohyla
           leonhard-schultzei_ Ahl. Studies of American Hylid
           Frogs. IV. Herpetologica, 16:191-197, September 23.

STUART, L. C.

     1954. Descriptions of some new amphibians and reptiles from
           Guatemala. Proc. Biol. Soc. Washington, 67:159-178,
           August 5.

TAYLOR, E. H.

     1944. A new genus and species of Mexican hylid frogs. Univ.
           Kansas Sci. Bull., 30 (pt. 1):41-45, June 12.

_Transmitted January 23, 1961._


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Transcriber's Notes

Italicized text is shown within _underscores_.

Italicized bold text is shown within ~_tildes and underscores_~.

Page 352: Rejoined last paragraph, originally split by Plate 25.

Page 355: Changed typo "Comaprisons" to "Comparisons."








