Cavefish

Cavefish or cave fish, also known as hypogean fish, is a generic term for freshwater fish adapted to life in caves. Being aquatic, they are a part of the troglobite group known as stygofauna. The approximately 170 species of cavefish are found in all continents, except Antarctica and Europe. Although widespread as a group, many cavefish species have very small ranges and are seriously threatened. Cavefish are members of a wide range of families and do not form a monophyletic group. Typical adaptions found in cavefish are reduced eyes and pigmentation.