Oxydoras

Oxydoras is a genus of thorny catfishes native to tropical South America.

Species
There are currently three recognized species in this genus:
 * Oxydoras kneri Bleeker, 1862
 * Oxydoras niger (Valenciennes, 1821) (Ripsaw catfish)
 * Oxydoras sifontesi Fernández-Yépez, 1968

Description
Oxydoras species are relatively large, reaching between 70–100 centimetres (28–40 in) in length. O. kneri has a maximum published weight of 9 kg. O. niger gets even heavier, with a maximum published weight of 13 kg.