Catfish are a diverse group of ray-finned fish. Named for their prominent barbels, which resemble a cat's whiskers, catfish range in size and behavior from the three largest species alive, the Mekong giant catfish from Southeast Asia, the wels catfish of Eurasia, and the piraíba of South America, to detritivores, and even to a tiny parasitic species commonly called the candiru, Vandellia cirrhosa. Neither the armour-plated types nor the naked types have scales. Despite their name, not all catfish have prominent barbels or "whiskers". Members of the Siluriformes order are defined by features of the skull and swimbladder. Catfish are of considerable commercial importance; many of the larger species are farmed or fished for food. Many of the smaller species, particularly the genus Corydoras, are important in the aquarium hobby. Many catfish are nocturnal, but others are crepuscular or diurnal.
Callichthyidae is a family of catfishes, called armored catfishes due to the two rows of bony plates along the lengths of their bodies. It contains some of the most popular freshwater aquarium fish, such as many species in the genus Corydoras.
Loricariidae is the largest family of catfish, with 92 genera and just over 680 species. Loricariids originate from freshwater habitats of Costa Rica, Panama, and tropical and subtropical South America. These fish are noted for the bony plates covering their bodies and their suckermouths. Several genera are sold as "plecos", notably the suckermouth catfish, Hypostomus plecostomus, and are popular as aquarium fish.
The eel-tailed catfish, Tandanus tandanus, is a species of catfish of the family Plotosidae. This fish is also known as dewfish, freshwater catfish, jewfish, and tandan.
The Doradidae are a family of catfishes also known as thorny catfishes, raphael catfishes or talking catfishes. These fish are native to South America, primarily the Amazon basin and the Guianas.
The Aspredinidae are a small South American family of catfishes also known as the banjo catfishes, with about 43 species.
Hypophthalmus is a genus of long-whiskered catfishes native to freshwater in tropical and subtropical South America.
Acanthopoma annectens is a species of catfish of the family Trichomycteridae, and the only species of the genus Acanthopoma. This fish grows to about 12 centimetres (4.7 in) SL and originates from the upper and middle Amazon River. This species is parasitic, attacking like a leech and leaving wounds all over the fish which it attacks; it spreads a bundle of opercular and inter-opercular spines into the wound and remains there and is difficult to remove. It may invade parts of wading or swimming animals but apparently exist in these passages only for a short while, as they quickly die from a lack of oxygen.
Bagarius is an Asian genus of catfishes of the family Sisoridae. It includes five to six extant species and potentially one extinct fossil species, B. gigas.
The freshwater cobbler, Tandanus bostocki, is a species of catfish of the family Plotosidae. The freshwater cobbler originates from coastal drainages of southwestern Australia, from the Frankland River to the Moore River. The species may reach about 50 centimetres (20 in) total length.
The Cooper Creek catfish, also known as the Cooper Creek tandan, is a species of catfish of the family Plotosidae, and is the only species of the genus Neosiluroides. The species’ scientific name Neosiluroides came from the genus Neosilurus to which the Cooper Creek Catfish bears some resemblance. The second part of its name, cooperensis, is a reference to the sole location of the species in the Cooper Creek Catchment. It is an eel-tailed freshwater fish that resides in the Cooper Creek system of the Lake Eyre drainage in southern Queensland, Australia. This species grows up to about 46.0 centimetres (18.1 in) SL.
Paraplotosus is a genus of catfishes native to Australasia and South-east Asia.
Plotosus is a genus of eeltail catfishes native to the Indian Ocean, the western Pacific Ocean and New Guinea.
Synodontis batensoda, the upside-down catfish, is a species of mochokid upside-down catfish. It is unevenly distributed in inland waters across Africa from Senegal to Ethiopia, and is also known as a squeaker or giant upside-down catfish. It was originally described by Eduard Rüppell in 1832 in the paper "Continuation of the description and figure of several new fish, in the Nile. p1-14".
The bayad, is a species of bagrid catfish from Africa.
Cryptarius is a genus of catfishes of the family Ariidae. It includes two species, C. daugeti and C. truncatus. Cryptarius species originate from brackish waters of south and southeast Asia.
Batrachocephalus mino, the beardless sea catfish, is the only species of catfish in the genus Batrachocephalus of the family Ariidae. This species occurs in marine and brackish waters of Bay of Bengal, and parts of the western central Pacific, in coastal waters, estuaries, and lower reaches of rivers. It is distributed from Pakistan, India, Sri Lanka, Bangladesh, Myanmar, Malaysia, Thailand, to Indonesia.
Ketengus typus, the bigmouth sea-catfish, is the only species in the sea catfish genus Ketengus.
Galeichthys feliceps, the white barbel, sea barbel, white baggar or white sea catfish, is a species of sea catfish found in coastal waters and estuaries over muddy bottoms at depths of from 1 – 120 metres where they gather in large shoals. They occur from Namibia to South Africa with questionable records of sightings from Madagascar and Mozambique in Africa and the United States of America and Mexico in North America. It is coloured brown, grey or greenish-brown on the upperparts and is paler below. While most grow to a length of 35 cm, some individuals attain a length of 55 cm with a record of a fish from South Africa weighing 3.8 kg.
Neoarius graeffei, or blue salmon catfish, is a species of catfish found in freshwater rivers of Australia and Papua New Guinea. This species is most identifiable by its large, shark-like dorsal fin that is led by a poisonous spine. Like other catfish, the blue salmon catfish is known to use electrical pulses to sense prey in the water. This prey sensing mechanism may be the reason that these catfish are known to eat the land dwelling hopping mouse at a high rate.
