Catfish are any fish belonging to the order Siluriformes. Their name comes from their long barbels, or feelers, located around the mouth, which resemble cat whiskers. Catfish have at least one pair of barbels on the upper jaw, and they may also have pairs on the snout and chin. Most catfish species live in fresh water, but some live in marine environments. They are generally bottom dwellers and are more active at night. Catfish are scavengers and consume almost any animal or vegetable matter. There are nearly 2,900 known species of catfish.

Where are catfish commonly found?

Catfish, belonging to the order Siluriformes, are found worldwide in various freshwater habitats, from slow and stagnant waters to fast mountain streams. A few catfish species, in the families Ariidae and Plotosidae, are marine, inhabiting tropical shore waters. As bottom dwellers, catfish are generally more active at night, scavenging for almost any animal or vegetable matter. Several structural adaptations allow some catfish species (Balitoridae, Sisoridae, Akysidae, Loricariidae, Astroblepidae) to live in the upper regions of small mountain streams with torrential currents. Other catfish species are adapted to subterranean waters, wells, and caves.

How can you recognize a catfish?

Catfish, belonging to the order Siluriformes, can be recognized by their distinctive barbels, which are slender, tactile, whisker-like projections located around the mouth. These barbels, numbering at least one pair on the upper jaw, and possibly additional pairs on the snout and chin, aid in locating food. Many catfish species have spines in front of their dorsal and pectoral fins, which can be associated with venom glands capable of causing painful injuries. Catfish are either naked or armored with bony plates, but they lack scales. They also possess soft rays in the fins, and most have an adipose fin, a fleshy structure between the dorsal and caudal fins.

What do catfish eat in their natural habitats?

Catfish are generally bottom dwellers who are more active at night than during the day. Most are scavengers and will feed on almost any kind of animal or vegetable matter. In the flooded forests of the Amazon, catfish will feed on seeds and fruit for a significant part of the year. The goonch catfish of India has been recorded feeding on human remains from funeral pyres.

How do catfish defend themselves from predators?

Catfish have several defense mechanisms against predators. Many catfish species possess spines on their dorsal and pectoral fins, which offer protection. In some catfish, such as bullheads and madtoms, these spines have venom glands at their base that inject venom when the skin of a predator is punctured, causing a painful injury. Many smaller catfish species rely on protective coloration for defense. Some catfish species also exhibit specialized behaviors to avoid predators. For example, most catfish are nocturnal, remaining hidden during the day and hunting for food at night.

Why are catfish important to people and the environment?

Catfish, belonging to the order Siluriformes, are important to both people and the environment. Many of the larger catfish species are edible and serve as food sources, especially in North America, where they are prepared and enjoyed in various ways. In the ecosystem, catfish are generally bottom dwellers, often more active at night, and act as scavengers, consuming almost any available animal or vegetable matter. Some catfish species also help control populations of other organisms, contributing to the balance of their ecosystems.

catfish

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Illustration of a goonch catfish (Bagarius bagarius), a large freshwater fish about 6 feet long, showing its elongated body, whisker-like barbels, and distinctive dark markings.

Illustration of a blue catfish with a long, slender body, bluish-gray coloring, whisker-like barbels around the mouth, and prominent fins.

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Related Topics:: whalelike catfish; eeltail catfish; Trichomycteridae; bumblebee catfish; banjo catfish

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catfish

fish, order Siluriformes

Also known as: Siluriformes

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Top Questions

What are catfish?
Catfish are any fish belonging to the order Siluriformes. Their name comes from their long barbels, or feelers, located around the mouth, which resemble cat whiskers. Catfish have at least one pair of barbels on the upper jaw, and they may also have pairs on the snout and chin.

Most catfish species live in fresh water, but some live in marine environments. They are generally bottom dwellers and are more active at night. Catfish are scavengers and consume almost any animal or vegetable matter. There are nearly 2,900 known species of catfish.
3 Britannica Sources
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
Where are catfish commonly found?
Catfish, belonging to the order Siluriformes, are found worldwide in various freshwater habitats, from slow and stagnant waters to fast mountain streams. A few catfish species, in the families Ariidae and Plotosidae, are marine, inhabiting tropical shore waters. As bottom dwellers, catfish are generally more active at night, scavenging for almost any animal or vegetable matter.

Several structural adaptations allow some catfish species (Balitoridae, Sisoridae, Akysidae, Loricariidae, Astroblepidae) to live in the upper regions of small mountain streams with torrential currents. Other catfish species are adapted to subterranean waters, wells, and caves.
3 Britannica Sources
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
How can you recognize a catfish?
Catfish, belonging to the order Siluriformes, can be recognized by their distinctive barbels, which are slender, tactile, whisker-like projections located around the mouth. These barbels, numbering at least one pair on the upper jaw, and possibly additional pairs on the snout and chin, aid in locating food.

Many catfish species have spines in front of their dorsal and pectoral fins, which can be associated with venom glands capable of causing painful injuries. Catfish are either naked or armored with bony plates, but they lack scales. They also possess soft rays in the fins, and most have an adipose fin, a fleshy structure between the dorsal and caudal fins.
4 Britannica Sources
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
What do catfish eat in their natural habitats?
Catfish are generally bottom dwellers who are more active at night than during the day. Most are scavengers and will feed on almost any kind of animal or vegetable matter. In the flooded forests of the Amazon, catfish will feed on seeds and fruit for a significant part of the year. The goonch catfish of India has been recorded feeding on human remains from funeral pyres.
3 Britannica Sources
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
How do catfish defend themselves from predators?
Catfish have several defense mechanisms against predators. Many catfish species possess spines on their dorsal and pectoral fins, which offer protection. In some catfish, such as bullheads and madtoms, these spines have venom glands at their base that inject venom when the skin of a predator is punctured, causing a painful injury.

Many smaller catfish species rely on protective coloration for defense. Some catfish species also exhibit specialized behaviors to avoid predators. For example, most catfish are nocturnal, remaining hidden during the day and hunting for food at night.
5 Britannica Sources
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
Why are catfish important to people and the environment?
Catfish, belonging to the order Siluriformes, are important to both people and the environment. Many of the larger catfish species are edible and serve as food sources, especially in North America, where they are prepared and enjoyed in various ways.

In the ecosystem, catfish are generally bottom dwellers, often more active at night, and act as scavengers, consuming almost any available animal or vegetable matter. Some catfish species also help control populations of other organisms, contributing to the balance of their ecosystems.
3 Britannica Sources
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

catfish, any of the fishes of the order Siluriformes. Catfishes are related to the characins, carp, and minnows (order Cypriniformes) and may be placed with them in the superorder Ostariophysi. Some authorities, however, have regarded these groups as suborders, rather than a single order, and have classified them as the suborders Siluroidea (catfishes) and Cyprinoidea (characins, carp, and minnows) of the order Cypriniformes or Ostariophysi.

The name catfish refers to the long barbels, or feelers, which are present about the mouth of the fish and resemble cat whiskers. All catfishes have at least one pair of barbels, on the upper jaw; they may also have a pair on the snout and additional pairs on the chin. Many catfishes possess spines in front of the dorsal and pectoral fins. These spines may be associated with venom glands and can cause painful injuries to the unsuspecting. All catfishes are either naked or armoured with bony plates; none has scales.

Living catfishes constitute nearly 2,900 species placed in about 35 families. The majority of species inhabit fresh water, but a few, belonging to the families Ariidae and Plotosidae, are marine. Freshwater catfishes are almost worldwide in distribution and live in a variety of habitats from slow or stagnant waters to fast mountain streams; marine catfishes are found in the shore waters of the tropics. Catfishes are generally bottom dwellers, more active by night than by day. Most are scavengers and feed on almost any kind of animal or vegetable matter. All species are egg layers and may exhibit various types of parental care. The brown bullhead (Ictalurus nebulosus), for example, builds and guards a nest and protects its young, while male sea catfishes (Ariidae) carry the marble-sized eggs, and later the young, in their mouths.

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Catfishes vary considerably in size. Small species, such as the dwarf Corydoras, or micro cat (C. hastatus), may be as little as 4 or 5 centimetres (1 1/2–2 inches) long, while the wels (Silurus glanis), a large, European species, may be 4.5 metres (15 feet) in length and 300 kilograms (660 pounds) in weight. A number of the smaller species, especially those of the genus Corydoras, are popular aquarium fishes, while many of the larger catfishes are edible and used as food. Notable examples of the latter are the many North American food and sport fishes of the family Ictaluridae, among them the blue catfish (Ictalurus furcatus), with a maximum length and weight of 1.5 metres and 68 kilograms, and the channel catfish (I. punctatus), growing to about 1 metre and 12 kilograms.

The ictalurids are more or less typical catfishes; others, however, may be distinctive in appearance or behaviour. The glass catfish (Kryptopterus bicirrhus), for example, is a popular aquarium fish of the family Siluridae noted for its slender, highly transparent body; the banjo catfishes (Aspredinidae) of South America are slim fishes with rough, flattened heads and from above somewhat resemble banjos; the electric catfish (Malapterurus electricus) of Africa can generate up to 450 volts of electricity; the parasitic catfish, or candiru (Vandellia cirrhosa), of South America sometimes invades the urogenital openings of bathers; the talking catfish (Acanthodoras spinosissimus) is an armoured, Amazonian species that makes grunting sounds; the upside-down catfishes (Synodontis batensoda and others) of the family Mochokidae habitually swim upside down; the walking catfish (Clarias batrachus) is an air breather of the family Clariidae that can travel overland.

For more information about catfish species and groups, see bullhead; candiru; corydoras; electric catfish; madtom; wels. The catfish is also important in aquaculture.

This article was most recently revised and updated by Richard Pallardy.

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