Syncope bassleri
—
Bassler’s Sheep Frog
Also known as:
Bassler’s Humming Frog
This species was included in the genus Chiasmocleis until a major revision of the Microhylidae family by de Sá et al in 2012.

This is a very small frog; a full-sized adult like this one is still only about an inch long. Like all the other "sheep frogs" (a.k.a. "narrow-mouthed toads"), they are weird-looking little wedge-headed things.
Here is a complete list of the herps I saw in the wild on my 2014 MT Amazon Expeditions trip.
Online references:
- Syncope bassleri account on AmphibiaWeb
- Syncope bassleri account on Amphibian Species of the World
Printed references:
- Bartlett, R.D., and Bartlett, P. 2003. Reptiles and Amphibians of the Amazon: An Ecotourist's Guide
- Duellman, W.E. 2005. Cusco Amazónico: The Lives of Amphibians and Reptiles in an Amazonian Rainforest
- Rodríguez, L. O. and Duellman, W. E. 1994. Guide to the Frogs of the Iquitos Region, Amazonian Peru