The XO Directory

The Indonesian frog named Barbourula Kalimantanensis is the first lungless frog discovered. It breath entirely through its skin and lacks lungs. This trait may have evolved because of the amphibian's habitat of oxygen-rich, fast-moving water—which might more easily carry away a frog with air-filled lungs.

"Nobody knew about the lunglessness before we accidentally discovered it doing routine dissections," study lead author David Bickford, a biologist at the National University of Singapore, said in an email. His colleague Djoko Iskandar at the Bandung Institute of Technology in Indonesia first discovered two specimens of the frog in 1978.

Link