The redtail catfish, Phractocephalus hemioliopterus, is a pimelodid (long-whiskered) catfish. In Venezuela, it is known as cajaro, and in Brazil, it is known as pirarara, stemming from the Tupi language words pirá and arara. It is the only extant species of the genus Phractocephalus. This fish is common in the aquarium trade, although its massive adult size makes it unsuitable for all but the largest aquariums. They feed on fish, crustaceans and fallen fruits. They are not evaluated by IUCN. Phractocephalus hemioliopterus can reach about 1.8 m (5 ft 11 in) in length, and about 80 kg (180 lb) in weight. However, this is exceptionally rare, and most do not approach this size. They average 3 ft 6 in – 4 ft 6 in; 1.1–1.4 m in length. These colorful large catfishes have a brownish back, with yellow sides, and characteristic orange-red dorsal fin and caudal fin (hence the common name). (Source: Wikipedia.org, CC BY-SA)