Frog Blog: The Slim-fingered Rain Frog Craugastor crassidigitus

Slim-fingered Rain Frog (Craugastor crassidigitus)
Sarapiqui, Costa Rica

The Slim-fingered Rain Frog (Craugastor crassidigitus) is a small frog of the Central American rainforests through Costa Rica south into Central Panama. Like most of the other Robber and Rain frogs from the genera Craugastor, Diasporus and Pristimantis, this is a highly variable species and can be difficult to identify in the field. They are tan or orange with a tuberculate skin and long toes with flat toe pads. Of course, that describes many similar species of these genera in Central America.

There are two types of calls associated with C. crassidigitus. One call is described as a "bird-like chirp" while another has been described as a "chuck chirp". The chuck chirp is believed to be used for territorial communication. It was described in Roberto Ibanez's CD of Panamanian Frog calls as the "sporadic call".

I hear this call as sort of a "hoarse chirp".

I recorded what I presume to be the chirp calls as we walked along a dirt road in the Anton Valley of Panama. The frogs were calling from a heavily vegetated hillside next to the road. Even though there were lots of these frogs calling, as is typical, we had a hard time finding the singers.

We eventually did find one of these frogs and see it making this call. Unfortunately, my photo of that individual "left something to be desired" 🤣.