Comprehensive DescriptionRead full entry
Originally described by Cope (1894), the type specimen is catalogued in the American Museum of Natural History (AMNH 5463; Zweifel 1964). This species is a member of the palmipes group (Hillis and de Sa 1988). The snout is short, rounded and wide, with the interorbital area larger than the eyelids (Villa 1988). Dorsolateral folds are present and are broad, flat and glandular. The tongue is deeply notched. Toe tips are expanded and the webbing between the toes is reduced. The first finger of the male has a delicately rugose nuptial pad, which is the same color as the skin and visible only under magnification. Vocal sacs and slits are absent in this species. There is marked sexual dimorphism, with the female larger in size than the males. The dorsal folds are marked by bicolored stripes, and the folds themselves are dark brown with a lighter, usually narrow golden stripe above. The striping starts above the eye and runs the length of the body. Distinctively, the eye has a green iris (Zweifel 1964; Villa 1988).
Adult coloration is variable. Some individuals have a bright green dorsal color with small dark spots bordered in gold. In this form, the canthal region is brown, with the color fading beneath the eye and through the tympanic region until meeting the dorsolateral fold. A greenish gold stripe runs along the upper lip. Limbs are green dorsally, with some brown and gold speckling. The flanks, palms, and soles are pink to orange-red. In contrast, other individuals are reddish brown with darker dorsal spotting. In this second form, the dorsolateral folds are yellowish brown with a diffuse dark streak. The flanks and dorsal region of the limbs are also a yellowish brown. There is a loosely defined dark streak extending from the canthal region and continuing above and posterior to the tympanum. Both of these color variations are found in natural populations, Although Zweifel (1964) stated that "the green adults are decidedly in the minority," Villa (1988) noted no dominance of coloration pattern. The amount of spotting on individuals varies greatly also, from none at all to very large numerous spots.
The larvae are brown, paler in the tail fin, but without a definite pattern. Larger larvae develop an olive-green ground color with dark spotting. The mouth is small, with a single continuous row of denticles followed by four rows divided by the upper beak. The first lower row is also continuous, followed by a maximum of three uninterrupted rows (Villa 1988).
The specific name is derived from the Latin word vibicis, meaning the mark of a whip, in reference to the distinctive dorsolateral folds (Villa 1988).
A Spanish-language species account can be found at the website of Instituto Nacional de Biodiversidad (INBio).