Pristimantis martiae
—
Marti’s Rain Frog

I think this one is Pristimantis martiae based in part on the longitudinal stripes and snout shape. My backup guess is Pristimantis altamazonicus. It's a shame I didn't spend a little more time to get a good photo of this little guy.
My Travelogues and Trip Lists page includes a complete list of the herps I saw in the wild on my 2016 MT Amazon Expeditions trip.
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
- Duellman, W.E. and Lehr, E. 2009. Terrestrial-breeding Frogs (Strabomantidae) in Peru
- Rodríguez, L. O. and Duellman, W. E. 1994. Guide to the Frogs of the Iquitos Region, Amazonian Peru