Hylidae, Rafinesque, 1815

Barrio-Amorós, César L. & Brewer-Carías, Charles, 2010, Venezuelan Guayana, with the description of five new species, Zootaxa 1942, pp. 1-68 : 26-27

Family Hylidae

During the course of several excursions to creeks in the foothills of Sarisariñama, as well as to the southern slopes, we found a distinctive population of stream-inhabiting Hypsiboas of the H. benitezi group (sensu lan Guiana Shield ( Donnelly and Myers 1991; Myers and Donnelly 1997; Rivero 1961, 1971) and from one locality in Brazil, near the Venezuelan border ( Heyer 1994 a). It has also been reported from Jaua-tepui, Auyan-tepui, and Quebrada de Jaspe in the Gran Sabana ( Gorzula and Señaris 1999). Upon comparing specimens from Guaquinima and from Tamacuari, Myers and Donnelly (1997) suggested the possibility of a complex of at least two species.

Among the known specimens of H. benitezi , we were also able to recognize two populations. One of these ranges to the west of the Sierras de Maigualida and Parima (specimens from Duida-Marahuaka, upper Orinoco and Tapirapecó) and this population is referable to H. benitezi . The other ranges to the east of that range (including the areas of Jaua-Sarisariñama, Auyan-tepui, Gran Sabana, Guaiquinima, and Vila Pacaraima). The specimens from Guaiquinima ( Donnelly and Myers 1991) and Vila Pacaraima, Brazil ( Heyer 1994a) are smaller (males SVL 31–36 mm, females 36–47 mm in Guaiquinima; 32.1–36.5 mm for males, 43.6 mm in one Brazilian female) than individuals from Tamacuari (males 38.4–43.5 mm, females 44.9–51.4 mm; Myers and Donnelly 1997), or from Duida (males to 42.5 mm, females to 47.0 mm; Rivero 1971). Based on the size of specimens from Sarisariñama these are most like specimens from eastern populations ( Table 1). Furthermore there is a discrete ridge of ulnar tubercles in the specimens from Duida and Tamacuari, which is absent in the specimens from Guaiquinima and Sarisariñama. The calls from Guaiquinima and Brazil are virtually identical and consist of 3–5 notes with frequencies always higher than 2000 Hz. Those from Tamacuari produce 2 or 3 notes with frequencies lower than 2000 Hz; furthermore, note duration of Tamacuari recordings are longer ( Myers and Donnelly 1997). Thus, we are confident that the specimens from Guaquinima, Sarisariñama, and Vila Pacaraima constitute an unnamed taxon and that the larger frogs from Duida- the upper Orinoco and Ventuari rivers are separated from the Caura, Paragua, and Caroní drainages. Other examples following the same biogeographic pattern are Oreophrynella (to the east) and Metaphryniscus (to the west; Señaris et al. 1994), Leptodactylus rugosus (to the east) and L. lithonaetes (to the west; Heyer 1995; Heyer and Heyer, 2001; Heyer and Thompson 2000), Otophryne robusta (to the east) and O. pyburni (to the west; Barrio-Amorós 1998 a), Bothriopsis bilineata bilineata to the east, and B. b. smaragdina to the west ( Campbell and Lamar 2004), and by the absence of certain other species of Hypsiboas (e.g., H. lemai and H. sibleszi ) west of Maigualida and Parima (although a H. cf. sibleszi is mentioned from cerro Guanay, west of Maigualida, by Señaris and Ayarzagüena 2006, this must be confirmed).