Pristimantis diadematus Diadem Rain Frog
Some other names for this species:
Diadem Robber Frog
Madre Selva Biological Station, Loreto, PeruJanuary 13, 2014
Diadem Rain Frog (Pristimantis diadematus)
Every night we would see a handful of small, hard-to-identify Pristimantis species. I think this one is Pristimantis diadematus, and Dick Bartlett agreed.

Here is a complete list of the herps I saw in the wild on my 2014 MT Amazon Expeditions trip.

Madre Selva Biological Station, Loreto, PeruFebruary 1, 2016
Diadem Rain Frog (Pristimantis diadematus)
My book about this group of frogs in Peru says that Pristimantis diadematus does not have eyelid tubercles, but these frogs clearly have what I would call eyelid tubercles, albeit small ones. In all other respects these seem to be good examples of Pristimantis diadematus. One knowledgeable person told me that eyelid tubercles are a particularly unreliable character, so I am just going to ignore the whole eyelid tubercle situation and call these Pristimantis diadematus unless you (yes, you!) can convince me otherwise.

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.

Online references:
Printed references: