The first European cave fish

Subterranean biodiversity in Europe is spectacularly rich, with the Western Balkans being home to about 400 cave species, representing the highest number of species per area worldwide. Nonetheless, cave fish, which are the most commonly found vertebrates in underground habitats, have not been described in Europe so far. Two years ago the one was found by an accident by a cave diver, and this year was reported as the first European record of a cave fish population. It belongs to the genus Barbatula (shown in the picture), found in the Danube–Aach system, an underground karst water system in Southern Germany.

The fish exhibits characteristics typically observed in animals adapted to subterranean life including reduced eyes and pale body coloration.