Peters’ dwarf frog, Engystomops petersi, is a common leptodactylid frog (of the Edentulus clade; Ronet al. 2006) recently distinguished using molecular means and by call and morphometrics from closely-related cryptic species Engystomop freiberi (Funk et al. 2007; Funk et al. 2008). A wide-spread species, it is found in primary and secondary forests of the Andean foothills of Ecuador, Peru, and Bolivia, up to approximately 1200m, eastward through much of the Colombian, Brazilian, and French Guianan Amazon basin to the Atlantic (Funk 2008).
Peters’ dwarf frog is terrestrial, often found active in leaf-litter both nocturnally and diurnally.It breeds in temporary waterbodies and slow-moving streams during the wet season.Females lay eggs in foam nests in the water next to pools, and tadpoles develop in the water (Angulo 2010).
Although habitat loss has impacted local populations, E. petersi appears adaptable to modified habitats and forest edges, and found in protected areas, so is listed by the IUCN as of Least Concern for extinction (Duellman, 1978; Angulo 2010).However, evidence from call data suggests that E. petersi may in fact include other cryptic species, which may have implications for conservation.Research by Funk et al. 2008 suggest that barrier effects of rivers in the Amazon may have impacted the evolution of these terrestrial frogs, generating considerable genetic diversity and cryptic speciation among lineages on opposing sides of rivers (e.g. northwestern = upper Napo drainage of Ecuador and adjacent Peru; southwestern = Juruá and Madre de Díos drainages of Peru and adjacent Brazil, and eastern = Pará, Brazil).
Note: Engystomops was revalidated from the genus Physalaemus (Nascimento 2005).
