''Bagarius'' () is an Asian

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

catfish Catfish (or catfishes; order (biology), order Siluriformes or Nematognathi) are a diverse group of ray-finned fish. Catfish are common name, named for their prominent barbel (anatomy), barbels, which resemble a cat's whiskers, though not ...

es (

order Order, ORDER or Orders may refer to: * A socio-political or established or existing order, e.g. World order, Ancien Regime, Pax Britannica * Categorization, the process in which ideas and objects are recognized, differentiated, and understood ...

Siluriformes) of the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Sisoridae 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. Taxonomy The family Sisoridae is recog ...

. It includes five to six

extant Extant or Least-concern species, least concern is the opposite of the word extinct. It may refer to: * Extant hereditary titles * Extant literature, surviving literature, such as ''Beowulf'', the oldest extant manuscript written in English * Exta ...

species and potentially one

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

fossil species, '' B. gigas''.

Species

There are currently five to six extant species placed in ''Bagarius'': * '' Bagarius bagarius'' (

Hamilton Hamilton may refer to: * Alexander Hamilton (1755/1757–1804), first U.S. Secretary of the Treasury and one of the Founding Fathers of the United States * ''Hamilton'' (musical), a 2015 Broadway musical by Lin-Manuel Miranda ** ''Hamilton'' (al ...

, 1822) * '' Bagarius lica'' Volz, 1903 * '' Bagarius rutilus'' Ng & Kottelat, 2000 * '' Bagarius suchus'' Roberts, 1983 (crocodile catfish) * '' Bagarius vegrandis'' Ng & Kottelat, 2021 (dwarf goonch catfish) * '' Bagarius yarrelli'' (

Sykes "Sykes" is a surname of Anglo-Saxon English origins, which generally has topographical roots as it original linguistic origin. The name derives from the Old Norse word "sík" or "síkja", meaning a small stream, marshy hollow, or gully. It eventua ...

, 1839) (goonch catfish) (doubtfully distinct from '' B. bagarius'') A 2021 study found the giant devil catfish (''Bagarius yarrelli'') to be synonymous with ''B. bagarius''. ''Bagarius lica'' may be synonymous with ''Bagarius vegrandis''. One potential fossil species, '' Bagarius gigas,'' is known from the

Eocene The Eocene ( ) is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes ...

Sumatra Sumatra () is one of the Sunda Islands of western Indonesia. It is the largest island that is fully within Indonesian territory, as well as the list of islands by area, sixth-largest island in the world at 482,286.55 km2 (182,812 mi. ...

Distribution

''Bagarius'' species inhabit

south South is one of the cardinal directions or compass points. The direction is the opposite of north and is perpendicular to both west and east. Etymology The word ''south'' comes from Old English ''sūþ'', from earlier Proto-Germanic ''*sunþa ...

and

southeast Asia Southeast Asia is the geographical United Nations geoscheme for Asia#South-eastern Asia, southeastern region of Asia, consisting of the regions that are situated south of China, east of the Indian subcontinent, and northwest of the Mainland Au ...

. They are distributed in the

Indus The Indus ( ) is a transboundary river of Asia and a trans- Himalayan river of South and Central Asia. The river rises in mountain springs northeast of Mount Kailash in the Western Tibet region of China, flows northwest through the dis ...

drainage in

Pakistan Pakistan, officially the Islamic Republic of Pakistan, is a country in South Asia. It is the List of countries and dependencies by population, fifth-most populous country, with a population of over 241.5 million, having the Islam by country# ...

and

India India, officially the Republic of India, is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area; the List of countries by population (United Nations), most populous country since ...

, east (including peninsular India) to the Red River drainage in

Vietnam Vietnam, officially the Socialist Republic of Vietnam (SRV), is a country at the eastern edge of mainland Southeast Asia, with an area of about and a population of over 100 million, making it the world's List of countries and depende ...

and south throughout

Indochina Mainland Southeast Asia (historically known as Indochina and the Indochinese Peninsula) is the continental portion of Southeast Asia. It lies east of the Indian subcontinent and south of Mainland China and is bordered by the Indian Ocean to th ...

including the

Malay Peninsula The Malay Peninsula is located in Mainland Southeast Asia. The landmass runs approximately north–south, and at its terminus, it is the southernmost point of the Asian continental mainland. The area contains Peninsular Malaysia, Southern Tha ...

and

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania, between the Indian Ocean, Indian and Pacific Ocean, Pacific oceans. Comprising over List of islands of Indonesia, 17,000 islands, including Sumatra, ...

. ''B. bagarius'' is known from the

Ganges River The Ganges ( ; in India: Ganga, ; in Bangladesh: Padma, ). "The Ganges Basin, known in India as the Ganga and in Bangladesh as the Padma, is an international which goes through India, Bangladesh, Nepal and China." is a trans-boundary rive ...

Chao Phraya The Chao Phraya River is the major river in Thailand, with its low alluvial plain forming the centre of the country. It flows through Bangkok and then into the Gulf of Thailand. Etymology Written evidence of the river being referred to by the ...

, and the

Mekong The Mekong or Mekong River ( , ) is a transboundary river in East Asia and Southeast Asia. It is the world's twelfth-longest river and the third-longest in Asia with an estimated length of and a drainage area of , discharging of wat ...

drainages, as well as the Malay Peninsula and the

Salween The Salween is a Southeast Asian river, about long, flowing from the Tibetan Plateau south into the Andaman Sea. The Salween flows primarily within southwest China and eastern Myanmar, with a short section forming the border of Myanmar and Tha ...

and

Mae Klong The Mae Klong (, , ), sometimes spelled Meklong, is a river A river is a natural stream of fresh water that flows on land or inside Subterranean river, caves towards another body of water at a lower elevation, such as an ocean, lake, o ...

drainages and the

Brahmaputra River The Brahmaputra is a trans-boundary river which flows through Southwestern China, Northeastern India, and Bangladesh. It is known as Brahmaputra or Luit in Assamese language, Assamese, Yarlung Tsangpo in Lhasa Tibetan, Tibetan, the Siang/Dihan ...

and

Ayeyarwady River The Irrawaddy River (, , Ayeyarwady) is the principal river of Myanmar, running through the centre of the country. Myanmar’s most important commercial waterway, it is about 1,350 miles (2,170 km) long. Originating from the confluence of the ...

. ''B. suchus'' originates from the Mekong and Chao Phraya basins. ''B. rutilus'' inhabits the Red River and

Ma River Ma, MA, or mA may refer to: Academia * Master of Arts, a degree award * Marin Academy, a high school in San Rafael, California * Menlo-Atherton High School, a public high school in Atherton, California * Minnehaha Academy, a private high sch ...

in northern Vietnam.

Fossil record

''B. gigas'' is reportedly from the

of Sumatra, but the age of the locale has been questioned. The oldest known confirmed sisorid fossil is ''B. bagarius'' found in Sumatra and India of the

Pliocene The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58

Description

''Bagarius'' species have a broad head that is moderately or strongly depressed. The mouth is broad and terminal or slightly inferior. The

gill A gill () is a respiration organ, respiratory organ that many aquatic ecosystem, aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow r ...

openings are wide. The

dorsal fin A dorsal fin is a fin on the back of most marine and freshwater vertebrates. Dorsal fins have evolved independently several times through convergent evolution adapting to marine environments, so the fins are not all homologous. They are found ...

and

pectoral fin Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish aquatic locomotion, swim. Apart from the tail or caudal fin, fish fins have no direct connection with the vertebral column ...

s have strong spines. The dorsal fin spine is smooth, and the pectoral fin spine is smooth anteriorly and finely serrate posteriorly. The dorsal, pectoral, and

caudal fin Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported only ...

lobes sometimes with filamentous extensions. The head and body is entirely or almost entirely covered by heavily

keratin Keratin () is one of a family of structural fibrous proteins also known as ''scleroproteins''. It is the key structural material making up Scale (anatomy), scales, hair, Nail (anatomy), nails, feathers, horn (anatomy), horns, claws, Hoof, hoove ...

ized skin superficially differentiated into unculiferous plaques or

tubercle In anatomy, a tubercle (literally 'small tuber', Latin for 'lump') is any round nodule, small eminence, or warty outgrowth found on external or internal organs of a plant or an animal. In plants A tubercle is generally a wart-like projectio ...

s. ''Bagarius'' species lack a thoracic adhesive apparatus and paired fins are unplaited. ''Bagarius'' species have the same general colour pattern consisting of three darkly pigmented bands or blotches on the body. Irregularly placed spots may also be present on the body. The fin pigmentation varies from species to species, from plain, to spotted, to slightly or heavily barred. Also, some ''B. yarelli'' may have a heavily spotted pattern like a Dalmatian dog that obscures the main barred pattern. In ''B. bagarius'', the pelvic fin origin is normally anterior to a vertical line through the base of the last dorsal fin ray, while in ''B. yarelli'' the pelvic fin origin is posterior to this vertical line. Also, in most ''B. bagarius'', the

adipose fin Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported only b ...

originates far back over the

anal fin Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported o ...

, on a vertical through the base of the third or four anal fin ray. However, in most ''B. yarelli'', the adipose fin originates near or in front of a vertical line through the anal fin origin. In ''B. suchus'', the adipose fin originates even further back than in ''B. bagarius'' or ''B. yarelli''. ''B. suchus'' tends to have a flatter head and body than either ''B. bagarius'' or ''B. yarelli''. ''B. bagarius'' does not grow much past SL. ''B. rutilus'' grows to about SL. ''B. suchus'' grows to about SL. Both ''B. yarelli'' and ''B. lica'' grow very large, reaching about SL.

Ecology

''B. bagarius'' inhabits rapid and rocky pools of large and medium-sized rivers. ''B. suchus'' is usually associated with rapids in the large rivers it inhabits. ''B. yarelli'' occurs in large rivers on the bottom, even with swift current, never entering small streams. It is found among boulders, often in the white water of the rapids where it apparently is indifferent to the strong current. ''B. bagarius'' is primarily

entomophagous Entomophagy (, from Greek ἔντομον ', 'insect', and φαγεῖν ', 'to eat') is the practice of eating insects. An alternative term is insectivory. Terms for organisms that practice entomophagy are ''entomophage'' and ''insectivore'' ...

. It also feeds on small fishes, frogs and shrimps. ''B. suchus'', however, is a

piscivore A piscivore () is a carnivorous animal that primarily eats fish. Fish were the diet of early tetrapod evolution (via water-bound amphibians during the Devonian period); insectivory came next; then in time, the more terrestrially adapted repti ...

. ''B. yarelli'' feeds primarily on

prawn Prawn is a common name for small aquatic crustaceans with an exoskeleton An exoskeleton () . is a skeleton that is on the exterior of an animal in the form of hardened integument, which both supports the body's shape and protects the intern ...

s but also eat small fishes and aquatic insects. ''B. bagarius'' breeds in rivers prior to the beginning of the annual flood season. ''B. yarelli'' migrates in schools. It is reported to migrate to follow its prey. It is also reported that it follows '' Catlocarpio siamensis'' during its upstream migration. Apparently the main upstream migration begins close to the peak of flood, when the current is very strong and the water is turbid.

Relationship to humans

''Bagarius'' species are marketed fresh, and are important as a food fish, but the meat spoils rapidly and can cause illness. The goonch catfish ''B. yarrelli'' has become an object of media attention as reports have surfaced of some of these fish feeding on funeral

pyre A pyre (; ), also known as a funeral pyre, is a structure, usually made of wood, for burning a body as part of a funeral rite or execution. As a form of cremation, a body is placed upon or under the pyre, which is then set on fire. In discussi ...

s in the Kali River. There is speculation that some drownings have also been caused by large specimens that have "developed a taste" for human flesh from the corpses and subsequently have attacked bathers in the river. This is the subject of a TV documentary aired on 22 October 2008, as well as an episode about the

Kali River goonch attacks The Kali River goonch attacks were a series of fatal Animal attacks, attacks on humans believed to be perpetrated by a Bagarius yarrelli, goonch weighing in three villages on the banks of the Kali River (Uttarakhand), Kali River in India and Nep ...

on the

Animal Planet Animal Planet (stylized in all lowercase since 2018) is an American multinational pay television channel focusing on the animal kingdom owned by the Warner Bros. Discovery Networks unit of Warner Bros. Discovery. First established on June 1 ...

series ''

River Monsters ''River Monsters'' is a British wildlife Documentary film, documentary television series produced for Animal Planet by Icon Films of Bristol, United Kingdom. It is hosted by Angling, angler and biologist Jeremy Wade, who travels around the gl ...

''.

References

{{Taxonbar, from=Q1850503 Freshwater fish of China Freshwater fish of India Fish of Pakistan Fish of South Asia Fish of Southeast Asia Fish of Vietnam Freshwater fish genera Sisoridae Catfish genera Taxa named by Pieter Bleeker