Regardless of what it is called, this is a widespread and conspicuous frog of the Central American lowlands. It isn't conspicuous because of any particular abundance, rather it is conspicuous because of its enormous size. This is one of the largest frogs in the New World and an adult can be 20cm (almost 8 inches) long and weigh several pounds.
They are voracious predators of the neotropical forest floor and will eat anything they can fit in their sizeable gape!
This is the only photo I have of this species. It was calling in a roadside ditch just north of Aguas Zarcas, Costa Rica. I heard it calling, pulled over and managed snap one photo before it rocketed into the culvert under the road and disappeared.
In the photo, you can see one interesting characteristic of this species. The males have enormously distended forearms during the breeding season, presumably to hold on to the big females for breeding. They must have quite the grip! You can see how "pumped up" this male is in this photo.
I was unable to record this individual before he ran off, but a few miles west of there I was able to record a large chorus of the species in a flooded grassy creek between two houses.
Their loud "whooop, whooop" calls are one of my favorite sounds of the Central American tropics. The distance they can echo through a forest at night is amazing.
© Chris Harrison 2014