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.
Trichomycteridae is a family of catfishes commonly known as pencil catfishes or parasitic catfishes. This family includes the candiru fish, feared by some people for its alleged habit of entering into the urethra of humans. They are one of the few parasitic chordates. Another species is the life monsefuano which was important to the Moche culture and still an important part of Peruvian cuisine.
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 Bagridae are a family of catfish that are native to Africa (Bagrus) and Asia from Japan to Borneo. It includes about 245 species. These fish are commonly known as naked catfishes or bagrid catfishes.
The loach catfishes are a family, Amphiliidae, of catfishes. They are widespread in tropical Africa, but are most common in streams at high elevations; most species are able to cling to rocks in fast-flowing streams. The 13 genera contain 68 species.
Sisoridae is a family of catfishes. These Asian catfishes live in fast-moving waters and often have adaptations that allow them to adhere to objects in their habitats. The family includes about 235 species.
Rineloricaria is a genus of freshwater tropical catfish belonging to the family Loricariidae. They are commonly called whiptail catfish because of the long filament that grows out of the tip of the caudal fin that is characteristic of the genus. With the exception of R. altipinnis from Panama, they are native to the rivers of northern and central South America. Some species are regularly seen in the aquarium trade.
Synodontis is the largest genus of mochokid catfishes. It is the biggest genus within the 10 genera and 190 different species in the family Mochokidae. Synodontis has over 131 different species within the genus. Synodontis are also known as squeakers, due to their ability to make stridulatory sounds through their pectoral fin spines when handled or disturbed. Synodontis make a sound that sounds like squeaking by rubbing their spines together. They do this when they have been frightened or when they become angry. Synodontis may also squeak when they are taken out of the water. These catfish are small- to medium-sized fish with many species exhibiting attractive spotted markings. Some species are also known for naturally swimming belly-up, earning the name upside-down catfish. Some of these species are Synodontis contractus and Synodontis nigriventris. While some of these species are known to swim upside down, another species, Synodontis multipunctatus, is a brood parasitic cuckoo catfish,there are two other species Synodontis petricola and Synodontis grandiops are also called brood parasitic cuckoo catfish.
Andersonia leptura is a species of catfish of the family Amphiliidae, and is the only species of the genus Andersonia. This fish grows to about 50.0 cm (19.7 in) in total length; it is found in the Omo, Niger, and Upper Nile Rivers and the Lake Chad basin, and is also known from Lake Debo. Although previously considered to be toothless on the lower jaw, dentition has been found on the premaxilla and the dentary. The teeth are embedded in the mucous sheath that covers the head and extends into the oral cavity, which makes the teeth difficult to see with the naked eye.
Gogo is a small genus of catfishes of the family Anchariidae. It includes four species.
Belonoglanis is a genus of catfishes of the family Amphiliidae. Both species occur in the Congo River basin.
Chiloglanis is a genus of upside-down catfishes native to Africa. These species have modified lips and barbels that form a suckermouth. They also have a naked (scaleless) body. Sexual dimorphism has been reported in Chiloglanis. The adult males of many of these species have elongate anal and caudal fins. Also, males may have an enlarged humeral process.
Amphilius is a genus of catfishes of the family Amphiliidae.
Doumea is a genus of loach catfishes native to Africa.
Tetracamphilius is a genus of catfishes of the family Amphiliidae. It includes four species.
Galeichthys is a genus of sea catfishes in the family Ariidae, the only genus in the subfamily Galeichthyinae. It includes four predominantly marine species distributed in Southern Africa and northwestern South America:
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.
Congoglanis alula is a species of loach catfish found in the Congo River Basin in Angola, the Democratic Republic of Congo and possibly in Zambia. It reaches lengths up to 14.1 centimetres (5.6 in) SL.
Congoglanis is a genus of loach catfishes found in the Congo River system of Africa. This genus is considered the sister group of all other species in the subfamily Doumeinae.
