Herpetofauna of the Yutajé–corocoro Massif, Venezuela: Second Report From the Robert G. Goelet American Museum–terramar Expedition to the Northwestern Tepuis
Year: 2001
Type: article
Abstract: The Yutaje ´-Corocoro massif is a highly eroded sandstone table mountain, with internal drainage mainly to the central valley of the Rı ´o Corocoro, a stream in the headwater drainage of the Rı ´o Manapiare-some 100 km east of the middle Rı ´o Orinoco, at the northern edge of the State of Amazonas in southern Venezuela.The rocky soil supports a mosaic of diverse scrubland and forest, with small tepui meadows at the higher elevations.The herpetofauna is depauperate, as is typical of the Venezuelan tepuis.Eight species of amphibians and reptiles were collected during a 7-day period in the dry season (February).This sample includes two new frogs (Hyalinobatrachium eccentricum, n. sp., Centrolenidae; Colostethus undulatus, n. sp., Dendrobatidae) and a new genus and species of lizards (Adercosaurus vixadnexus, n. gen.& sp., Teiidae), all of which were found in humid montane mossy forest at 1700-1750 m elevation.Another new lizard (Tropidurus panstictus, n. sp., Tropiduridae) was discovered at lower elevations (180-1220 m), especially in dry scrub.The fauna also includes a widespread lowland frog (Pseudopaludicola llanera Lynch), two tepui frogs (Eleutherodactylus cantitans Myers and Donnelly; E. yaviensis Myers and Donnelly), a tepui lizard (Prionodactylus goeleti [Myers and Donnelly], new combination), a snake (Liophis?) that escaped capture, and another snake (Thamnodynastes corocoroensis Gorzula and Ayarzagu ¨ena) obtained by S. Gorzula in 1987.The two Eleutherodactylus and the Prionodactylus also occur on neighboring Cerro Yavı ´(the type locality), although one of the frogs (E.yaviensis) and the lizard show evidence of differentiation.Based on the original description, the snake Thamnodynastes corocoroensis appears to be distinct from a related species on Cerro Yavı ´.Two of the new species exhibit characters that are novel or not previously noted.The dendrobatid frog Colostethus undulatus, n. sp. has a glandular supracarpal pad atop the wrist, being best developed in males.This species, which also has the parasphenoid bone curiously concealed, seems to be unusual among tepui Colostethus in lacking the recently described median lingual process.The centrolenid frog Hyalinobatrachium eccentricum, n. sp. has a peculiar bicolored iris, with a dark median sector that conceals the pupil and which apparently dilates with the pupil.This character is retained in preservative and differentiates H. eccentricum from H. crurifasciatum Donnelly and Myers.Both species share a previously overlooked bubblelike structure in the web between the third and fourth fingers, herein termed bulla (possibly parasite induced?). RESUMENEl macizo Yutaje ´-Corocoro es una meseta de piedra arenisca muy erosionada, con un drenaje interno central dirigido hacia el valle del Rı ´o Corocoro, un tributario del Rı ´o Manapiare en sus cabeceras, situado a unos 100 km al este del Rı ´o Orinoco, en el extremo norte del Estado Amazonas, Venezuela.El suelo rocoso sustenta un mosaico de arbustales y bosques diversos, con pequen ˜os herbazales tepuyanos en las zonas ma ´s altas.La herpetofauna del macizo esta ´depauperada como es tı ´pico en un tepui en Venezuela.Durante siete dı ´as en la temporada seca (febrero) se recolectaron ocho especies de anfibios y reptiles.La muestra incluye dos ranas nuevas (Hyalinobatrachium eccentricum, n. sp., Centrolenidae, y Colostethus undulatus, n. sp., Dendrobatidae) y un ge ´nero nuevo de lagartijas (Adercosaurus vixadnexus, n. gen., n. sp., Teiidae) todos colectados en el bosque hu ´medo montano (a 1700-1750 msnm).Tambie ´n se encontro ´otra especie nueva de lagarto (Tropidurus panstictus, n. sp., Tropiduridae) en las zonas ma ´s bajas (180-1220 msnm), especialmente en los arbustales secos.
Authors: CHARLES W. MYERS, MAUREEN A. DONNELLY
Language: English
Subfield: Global and Planetary Change
Field: Environmental Science
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W2180147889