The frog dubbed Barbourula Kalimnatanesis, is the first lungless frog ever discovered. In fact there are only a couple of other creatures - a kind of salamander and one snakelike amphibian that have no lungs.
The two-inch frog seems to breath through its skin, much like other frogs. However, it also has no airway opening in its throat and only a membrane lining in its thoracic cavity.
Animals developed lungs when they moved from the sea to land millions of years ago. Scientists believe this frog has evolved backwards - that is - it lost its lungs. While they don't know for sure, they believe it maybe because of extremely cold and rapid water streams, which have a lot of dissolved oxygen to absorb. Frogs have a low metabolism so do not need that much oxygen.
Scientists believe that by studying this backward evolution, they may be able to find out how lungs developed.