Book Description

"Based on field data and on examination of more than 3000 preserved specimens, species limits and distributions are defined for the frogs currently assigned to the fitzingeri group of Eleutherodactylus in the Chocoan lowlands (mainly below 1000 m. elev. in eastern Panama, western Colombia, and western Ecuador). Several of the species are abundant, ecologically important animals that have been repeatedly confused in the literature. Nine species are treated in detail and described and illustrated from living as well as preserved material, with natural history notes added where possible. Eleutherodactylus achatinus (Boulenger) occurs from Panama south to southwestern Ecuador; the names E. brederi Dunn and Hylodes pagmae are assigned to its synonymy (although brederi might yet prove to be a valid sibling species with a different call). Eleutherodactylus caprifer Lynch is known from west-central Colombia and northwestern Ecuador. These two species lack appreciable toe webbing. The following four species have moderate toe webbing: Eleutherodactylus fitzingeri (O. Schmidt) occurs from Nicaragua to west-central Colombia, being here treated primarily in the southern part of its range, where it has been confused with Eleutherodactylus raniformis (Boulenger)--a larger frog that occurs from eastern Panama south to west-central Colombia. Eleutherodactylus longirostris (Boulenger) occurs from the Darién highlands of extreme eastern Panama throughout western Colombia to southern Ecuador. All previous reports of longirostris in lower Central America seem to have been based on specimens either of fitzingeri or especially of Eleutherodactylus crassidigitus Taylor, whose range is extended out of Costa Rica and throughout the Isthmus of Panama to the Colombian border. However, the variation of crassidigitus remains inadequately studied and the redefined species might be a composite. E. crassidigitus differs from longirostris in color pattern, smaller size, and in a greater extent of toe webbing, although all specimens do not show these differences to the same degree. A closer relative (sister species) of longirostris may be the Central American E. talamancae Dunn. The remaining three species are streamside frogs having extensive toe webbing: Eleutherodactylus anomalus (Boulenger) is common in western Colombia and northwestern Ecuador. Eleutherodactylus anatipes, new species, is known only from northwestern Ecuador, and Eleutherodactylus zygodactylus, new species, is described from west-central Colombia. The fitzingeri group of Eleutherodactylus is especially diverse in the Chocoan lowlands. At most localities in South America, only two or three species are ever sympatric, but west of the Andes as many as seven species of the group co-occur in geographic sympatry, with species density being greatest in the region of the Río San Juan drainage of Colombia. Natural history data are fragmentary. The vocalizations and/or calling behavior of several species have characteristics that may reduce the frogs' vulnerability to sound-responsive predators"--P. 484.