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.
Synodontis nigriventris, the blotched upside-down catfish, is a species of upside-down catfish native to the Congo Basin of Cameroon, the Democratic Republic of the Congo and the Republic of the Congo.
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.
Corydoras is a genus of freshwater catfish in the family Callichthyidae and subfamily Corydoradinae. The species usually have more restricted areas of endemism than other callichthyids, but the area of distribution of the entire genus almost equals the area of distribution of the family, except for Panama where Corydoras is not present. Corydoras species are distributed in South America where they can be found from the east of the Andes to the Atlantic coast, from Trinidad to the Río de la Plata drainage in northern Argentina. Species assigned to Corydoras display a broad diversity of body shapes and coloration. Corydoras are small fish, ranging from 2.5 to 12 cm in SL., and are protected from predators by their body armor and by their sharp, typically venomous spines.
The brown bullhead is a fish of the family Ictaluridae that is widely distributed in North America. It is a species of bullhead catfish and is similar to the black bullhead and yellow bullhead. It was originally described as Pimelodus nebulosus by Charles Alexandre Lesueur in 1819, and is also referred to as Ictalurus nebulosus.
Electric catfish or Malapteruridae is a family of catfishes. This family includes two genera, Malapterurus and Paradoxoglanis, with 21 species. Several species of this family have the ability to generate electricity, delivering a shock of up to 350 volts from its electric organ. Electric catfish are found in tropical Africa and the Nile River. Electric catfish are usually nocturnal and carnivorous. Some species feed primarily on other fish, incapacitating their prey with electric discharges, but others are generalist bottom foragers, feeding on things like invertebrates, fish eggs, and detritus. The largest can grow to about 1.2 meters long, but most species are far smaller.
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 Cetopsidae are a small family of catfishes, commonly called the whale catfishes.
The Aspredinidae are a small South American family of catfishes also known as the banjo catfishes, with about 43 species.
The black bullhead or black bullhead catfish is a species of bullhead catfish. Like other bullhead catfish, it has the ability to thrive in waters that are low in oxygen, brackish, turbid and/or very warm. It also has barbels located near its mouth, a broad head, spiny fins, and no scales. It can be identified from other bullheads as the barbels are black, and it has a tan crescent around the tail. Its caudal fin is truncated. Like virtually all catfish, it is nocturnal, preferring to feed at night, although young feed during the day. It generally does not get as large as the channel or blue catfish, with average adult weights are in the 1-to-2-pound range, and almost never as large as 4 pounds (1.8 kg). It has a typical length of 6–14 inches (15–36 cm), with the largest specimen being 24 inches (61 cm), making it the largest of the bullheads. It is typically black or dark brown on the dorsal side of its body and yellow or white on the ventral side.
Chaca is the only genus in the catfish family Chacidae. These fish are commonly known as squarehead catfishes, frogmouth catfishes, or angler catfishes. These unusual fish have a sedentary lifestyle and spend much of their time motionless.
Sorubim is a small genus of long-whiskered catfish native to tropical South America. A number of characteristics allows the differentiation of each species in the genus. Sorubim species are important food fish in South America and are highly significant to fisheries of some areas; however, harvests of these fish are not identified as much as other, more popular food fishes such as Colossoma, Arapaima, and Brachyplatystoma. Some species of this family are popular aquarium fish.
Entomocorus is a genus of catfishes of the family Auchenipteridae.
Trachelyopterus is a genus of driftwood catfishes. They have been found in South American environments, including Venezuela, Colombia, Peru, Argentina, and several places in Brazil. They have a body pattern that follows bilateral symmetry and reproduce sexually. In terms of sensory systems, Trachelypterus’ have autoliths for hearing and lens eyes for seeing; they also have capabilities of electroreception. The size and appearance of different species within the Trachelyopterus genus varies, with sizes ranging from 5.5 inches in T. albicrux to 7.9 inches in T. insignis to 8.4 inches in T. lucenai. These small catfishes are marketed towards aquariums.
Entomocorus benjamini is a species of driftwood catfish found in the Madeira River system in Bolivia and Brazil. This species grows to a length of 7.0 cm and can be distinguished from it congeners in that the distal half of dorsal caudal fin lobe and the edge of the ventral lobe is pigmented.
Entomocorus gameroi is a species of driftwood catfish native to Venezuela and questionably present in Colombia. It is found in the Apure River basin. It grows to a length of 7.0 cm and can be distinguished from its congeners by an oblique band crossing from the dorsal profile of the caudal peduncle to the middle-upper rays of the caudal fin. E. gameroi is classified as an omnivore with a tendency towards insectivory; it has been found to eat cladocerans, copepods, and water mites, as well as ostracods, insects including coleopterans, dipterans, ephemeropterans, hemipterans, and seeds and other vegetal matter.
Silurus asotus, commonly called the Japanese common catfish, Amur catfish, Far Eastern catfish, and Chinese catfish, is a catfish species belonging to the Siluridae family. It lives in widespread distribution in freshwater habitats across East Asia and Japan. As a freshwater species, it can be found only in the catchments of rivers, ponds, and lakes located in China, Japan, the Korean Peninsula, Taiwan, and the Russian Amur Basin. This species of catfish is carnivorous and has a high aquaculture.
Trachelyopterus insignis is a species of catfish from the freshwater driftwood catfish family, Auchenipteridae. It is commonly found in rivers of northern South America, where it is called the chivo, the rengue, or the doncella.
Glanidium catharinensis is a species of driftwood catfish in the family Auchenipteridae. It is found in the Tubarão River basin in Santa Catarina, Brazil.
