Frogs Without Lungs!

But it's true! Here's the link to the story in the San Francisco Chronicle. It has no lungs, and breathes through its skin. They also say it kind of resembles a small version of Jabba the Hut from Star Wars. But it's well adapted to the streams it lives in, which is cold, rapidly moving streams that are rich in oxygen.

Maybe the lack of lungs keeps it less buoyant so that it isn't swept away in the current.

Evolutionarily it is related to other frogs that DO have lungs, and the biologists think that this may be an example of extreme evolutionary change in response to an environment.