A new species of Osteocephalus (Anura: Hylidae) from Amazonian Ecuador and Peru

A new species of the hylid frog genus Osteocephalus from the upper Amazon Basin of Ecuador and Peru is described. It most closely resembles O. planiceps, but it differs in the absence of pale stripes on the heels and above the vent, in being smaller, and lacking brown spots on the flanks. The new species, O. yasuni, is unique within Osteocephalus in having extensive yellow ventral coloration.