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.
The Ictaluridae, sometimes called ictalurids, are a family of catfish native to North America, where they are an important food source and sometimes fished for sport. The family includes about 51 species, some commonly known as bullheads, madtoms, channel catfish, and blue catfish.
The channel catfish is North America's most numerous catfish species. It is the official fish of Kansas, Missouri, Nebraska, and Tennessee, and is informally referred to as a "channel cat". In the United States, they are the most fished catfish species with around 8 million anglers targeting them per year. They also have very few teeth and swallow food whole. The popularity of channel catfish for food has contributed to the rapid expansion of aquaculture of this species in the United States. It has also been widely introduced in Europe, Asia and South America, and it is legally considered an invasive species in many countries.
The blue catfish is a large species of North American catfish, reaching a length of 65 in (170 cm) and a weight of 165 lb (75 kg). The continent’s largest, it can live to 20 years, with a typical fish being between 25–46 in (64–117 cm) and 30–70 lb (14–32 kg). Native distribution is primarily in the Mississippi River and Louisiana drainage systems, including the Missouri, Ohio, Tennessee, and Arkansas Rivers, the Des Moines River in south-central Iowa, the Rio Grande, and south along the Gulf Coast to Belize and Guatemala.
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 shark catfishes form the family Pangasiidae. They are found in fresh and brackish waters across southern Asia, from Pakistan to Borneo. Among the 30-odd members of this family is the plant-eating, endangered Mekong giant catfish Pangasianodon gigas, one of the largest known freshwater fish. Several species are the basis of productive aquaculture industries in Vietnam's Mekong Delta.
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.
Hoplosternum is a small genus of freshwater catfish in the Callichthyinae subfamily of the armored catfish family.
In fish anatomy and turtle anatomy, a barbel is a slender, whiskerlike sensory organ near the mouth. Fish that have barbels include the catfish, the carp, the goatfish, the hagfish, the sturgeon, the zebrafish, the black dragonfish and some species of shark such as the sawshark. Barbels house the taste buds of such fish and are used to search for food in murky water.
Cranoglanis is the only genus of armorhead catfishes.
The Anchariidae are a family of catfishes containing two genera, Ancharius and Gogo with 6 species. Anchariids are a strictly freshwater group endemic to Madagascar. Anchariids are characterized by the presence of fringed barbels and a reduced anterior nuchal plate.
Aguarunichthys is a genus of long-whiskered catfishes native to South America.
Hemibagrus is a genus of catfishes of the family Bagridae.
Pseudobagrus is a genus of bagrid catfishes that inhabit streams and rivers throughout East Asia. About half of these species occur in China.
Henonemus is a genus of pencil catfishes native to South America.
Amphilius is a genus of catfishes of the family Amphiliidae.
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:
Goeldiella eques is a species of three-barbeled catfish that occurs in the Guianas and the Amazon basin of Brazil, Peru and Venezuela. This fish reaches a length of 28.9 centimetres (11.4 in) SL. It is the only species of its genus.
Auchenipterus is a genus of driftwood catfishes.
