Stygichthys typhlops

Stygichthys typhlops, the Brazilian blind characid, is a small freshwater ray-finned fish and the only species in the genus Stygichthys, which belongs to the family Acestrorhamphidae, the American tetras. It lives only in caves in the north of Minas Gerais, Brazil. Like other cave-adapted fishes it is blind and lacks pigment, and it is only a few centimetres long. It is solitary, and individuals kept together in an aquarium are indifferent to one another. Known at first from a single specimen collected in 1962, it was rediscovered in 2004 by researchers led by the ichthyologist Cristiano Moreira of the University of Sao Paulo. Local people said it had been fairly common around Jaiba until the early 1990s, after which heavy water extraction lowered the water table and dried many wells and springs, a serious threat to its survival. Brazil recognises it as an endangered species.