Osteocephalus helenae (Ruthven 1919)

Holotype: UMMZ 52681.

Type locality: Valley of the Demerara River, Dunoon, Guyana.

Distribution: Region 5. Widely distributed in lowlands of Amazon Region (Bolivia, Peru, Colombia, Brazil, Colombia, Venezuela, Guyana, and French Guiana). In Venezuela, known from several localities in Bolívar and Delta Amacuro States (Barrio-Amorós 1998, Señaris and Ayarzagüena 2004).

Remarks: Osteocephalus helenae is the name that must apply to southern Venezuela’s green, tuberculated, medium-sized Osteocephalus . Specimens of this species in this region have been known under two names: Osteocephalus buckleyi (Boulenger 1882) with distribution now restricted to Upper Amazon in Peru, Colombia, and Ecuador (Jungfer et al. 2013); and Osteocephalus cabrerai (Cochran and Goin 1970), first reported from Venezuela by Gorzula and Señaris (1998). All specimens examined by Jungfer et al. (2013) from the Guiana Shield fall in the same clade, and only name O. helenae is applicable. In Osteocephalus buckleyi species group (Jungfer et al. 2013).

Selected references: Cochran and Goin (1970); Trueb and Duellman (1971); Duellman and Mendelson (1995); Gorzula and Señaris (1998); Señaris and Ayarzagüena (2004); Jungfer et al. (2013).