A New Hylid Frog from Eastern Mexico

BY

EDWARD H. TAYLOR

University of Kansas Publications Museum of Natural History

Volume 1, No. 15, pp. 257-264, 1 fig. in text
August 16, 1948

University of Kansas
LAWRENCE
1948

University of Kansas Publications, Museum of Natural History
Editors: E. Raymond Hall, Chairman; H. H. Lane, Edward H. Taylor

Volume 1, No. 15, pp. 257-264, 1 fig. in text
August 16, 1948

University of Kansas
Lawrence, Kansas

PRINTED BY
FERD VOILAND, JR., STATE PRINTER
TOPEKA, KANSAS
1948

22-3339

[Pg 259]

A New Hylid Frog from Eastern Mexico

By

EDWARD H. TAYLOR

A small collection of Mexican reptiles and amphibians recently acquired by the University of Kansas Natural History Museum contains five specimens of a species of the genus Hyla ( sensu lato ) which is here described as new.

Hyla proboscidea sp. nov.

Type. —University of Kansas Museum of Natural History, No. 23626, collected 2 km. west of Jico, Veracruz, Mexico, at an elevation of 4,200 ft., Oct. 28, 1946, by Walter W. Dalquest.

Paratypes. —Nos. 23624, 23625, 23627, 23628, collected with the type.

Diagnosis. —A medium sized member of the genus with known maximum length of male, 57 mm. Canthus rostralis well defined; tip of snout with a bulbous projection; fingers more than one-third webbed, foot nearly completely webbed; tympanum distinct; skin smooth above, granular below; very prominent inner metatarsal tubercle, small outer tubercle; tibiotarsal articulation reaches to nostril; a well-defined outer tarsal fold; anal opening ventral, covered by a free triangular flap; pupil of eye horizontal.

Description of the type. —Head longer than broad, the distance between the eye and nostril slightly greater than distance between nostril and tip of snout; canthus rostralis sharply defined, continued to above nostril; upper part of loreal region sloping abruptly, lower part sloping more gently to edge of lip; area in front of nostril somewhat swollen, the nostril large, directed strongly backward; tip of snout forming a short rounded proboscis; upper jaw rather strongly overhanging lower jaw.

Width of an upper eyelid contained in interorbital distance about 1-1/3 times; horizontal diameter of eye about equal to distance between eye and nostril, about 1-1/3 times diameter of tympanum; tympanum distinct, its distance from orbit equal to its diameter, overhung by a glandular fold running back from eye.

Choanae large; vomerine teeth in two elevated patches which lie between, and reach the posterior level, of choanae, the patches closer to each other than to choanae; tongue rather small, subcircular, not or but very indistinctly notched behind, not at all free behind; opening to vocal sacs behind level of tongue, the openings a short slit directed backwards. (Vocal sacs not evident externally in type or paratypes.)

Skin of dorsal surfaces generally smooth (under magnification surface minutely corrugated and wrinkled); ventral surface of abdomen, the thighs, and lower part of lateral surface of body strongly granulate, the granules unequal in size and elevation; breast, chin, and under side of arm with sparse granules or tubercles.

Anal opening ventral, covered by a small, free, triangular flap; a small thickened fold, slightly free, on each side of anus partly covered by triangular flap. [Pg 260]

Measurements (in mm.).—Snout to vent, 58; leg, 86; head length, 20; head width, 18.6.

Arms rather short, upper arm slender, forearm much thickened; a small axillary web present; disks on three outer fingers distinctly larger than tympanum, of first finger equal to or somewhat smaller than tympanum; outer fingers, between one-third and one-half webbed; on inner fingers webbing less than one-third; first finger more or less opposed to other three, its base widened, and the upper surface covered by a large patch of minute dark, horn-colored nuptial asperities, that extend to near the terminal disk; subarticular tubercles strongly elevated with numerous supernumerary tubercles on palm; a somewhat enlarged elevated palmar tubercle; under surface of forearm with a row of distinct tubercles; other smaller scattered granules present. Toes more than four-fifths webbed, the membrane reaching the base of the terminal disks, on one side at least, of all toes save fourth; subarticular tubercles strongly [Pg 261] elevated, with numerous supernumerary tubercles on sole; a large elevated inner metatarsal tubercle; a small outer tubercle; a continuous, well-defined, tarsal fold extending entire length of tarsus. Tibiotarsal articulation reaches nostril when leg is brought forward.

Color and marking. —General color of type (preserved in formalin, then transferred to alcohol) dull grayish purple, darker anteriorly and somewhat lighter and more mottled posteriorly; color very much lighter on sides with a few cream, dark-edged spots in groin and on sides of abdomen; front and back surfaces of thigh and shank with some darker and lighter flecking that is continued more or less on the foot. When submerged in water, very dim dark spots or bars visible on limbs; ventral surface dirty brownish flesh, without markings.

Variation. —The series consists of five adult male specimens. It is presumed that the female is considerably larger, and may lack the nasal proboscis which I suspect is a secondary sexual character.

There are some differences in the shade of coloring in the preserved specimens, some being darker, some lighter than the type. In two the lateral dark-edged, cream spots extend to the axilla, and the light and dark markings on the front and back surfaces of the leg are much more distinct in most of the specimens than in the type. When the specimens are submerged in water, the black bars on the limbs are evident in all specimens. The tympanum is sometimes darker, sometimes lighter than its surroundings.

In the field notes of Mr. Dalquest I find the statement that the color in life is bright yellow, which presumably applies to all of the specimens. No trace of this color remains at the present time.

The ventral granules of some of the paratypes are very unequal in elevation, some being elongated, nipplelike.

The following table gives the variation in measurements of the type and paratypes:

Measurements of Hyla proboscidea in mm.

Relationship. —It would appear that the relationship of this species is with Hyla bistincta , a widespread Mexican species likewise occurring in the same general area but at a much higher elevation. It also has an elongated flap which carries the anal opening nearly to the level of venter but the terminal part lacks the triangular flap. [Pg 262] There is no prolongation of the snout tip. There are also numerous other differences, so that it would be difficult to confuse the two forms.

Remarks. —This adds another very distinctive species to the Veracrucian fauna. Despite the fact that this state has probably been explored at greater length than any other Mexican state it still is a likely place for the discovery of novelties.

Transmitted April 8, 1948.