Clarias
Encyclopedia
Clarias is a genus
of catfish
es (order
Siluriformes) of the family
Clariidae, the airbreathing catfishes. The name is derived from the Greek
chlaros, which means lively, in reference to the ability of the fish to live for a long time out of water.
. It has been found that a species of Heterobranchus
(H. longifilis) clusters deeply inside the Clarias group.
, and is one of the most widespread catfish genera in the world. The genus is found in Southeast Asia
and East Asia
westwards through India
and the Asia Minor
to Africa
. The diversity of these catfishes is highest in Africa. Some (notably the Walking catfish
) have become pest species where they have been accidentally introduced.
and anal fins, which give them a rather eel
-like appearance. These fish have slender bodies, a flat bony head, and a broad, terminal mouth with four pairs of barbels
. They also have a large, accessory breathing organ composed of modified gill arches. Also, only the pectoral fins have spines.
and fish culture
.
African species
South Asian species
Southeast Asian species
Fossil species
, birds and amphibians. In Florida the fish is causing problems by invading aquaculture
farms and prey on the fish cultivated there. Countries where one or several Clarias species have been introduced includes Indonesia
, USA, Hong Kong
, Taiwan
, China
, UK, Papua New Guinea
, Guam
, Taiwan
, Thailand
and Cuba.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of catfish
Catfish
Catfishes 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 heaviest and longest, the Mekong giant catfish from Southeast Asia and the second longest, the wels catfish of Eurasia, to detritivores...
es (order
Order (biology)
In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...
Siluriformes) of the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Clariidae, the airbreathing catfishes. The name is derived from the Greek
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
chlaros, which means lively, in reference to the ability of the fish to live for a long time out of water.
Taxonomy
Clarias has been found to be paraphyleticParaphyly
A group of taxa is said to be paraphyletic if the group consists of all the descendants of a hypothetical closest common ancestor minus one or more monophyletic groups of descendants...
. It has been found that a species of Heterobranchus
Heterobranchus
Heterobranchus is a genus of catfishes of the family Clariidae.H. longifilis may also be known as the Vundu....
(H. longifilis) clusters deeply inside the Clarias group.
Distribution
They are found in inland waters throughout much of the Old WorldOld World
The Old World consists of those parts of the world known to classical antiquity and the European Middle Ages. It is used in the context of, and contrast with, the "New World" ....
, and is one of the most widespread catfish genera in the world. The genus is found in Southeast Asia
Southeast Asia
Southeast Asia, South-East Asia, South East Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India, west of New Guinea and north of Australia. The region lies on the intersection of geological plates, with heavy seismic...
and East Asia
East Asia
East Asia or Eastern Asia is a subregion of Asia that can be defined in either geographical or cultural terms...
westwards through India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
and the Asia Minor
Asia Minor
Asia Minor is a geographical location at the westernmost protrusion of Asia, also called Anatolia, and corresponds to the western two thirds of the Asian part of Turkey...
to Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
. The diversity of these catfishes is highest in Africa. Some (notably the Walking catfish
Walking catfish
The walking catfish, Clarias batrachus, is a species of freshwater airbreathing catfish found primarily in Southeast Asia, so named for its ability to "walk" across dry land, to find food or suitable environments...
) have become pest species where they have been accidentally introduced.
Description
Clarias species are recognized by their long-based dorsalDorsal fin
A dorsal fin is a fin located on the backs of various unrelated marine and freshwater vertebrates, including most fishes, marine mammals , and the ichthyosaurs...
and anal fins, which give them a rather eel
Eel
Eels are an order of fish, which consists of four suborders, 20 families, 111 genera and approximately 800 species. Most eels are predators...
-like appearance. These fish have slender bodies, a flat bony head, and a broad, terminal mouth with four pairs of barbels
Barbel (anatomy)
A barbel on a fish is a slender, whiskerlike tactile organ near the mouth. Fish that have barbels include the catfish, the carp, the goatfish, sturgeon, the zebrafish and some species of shark...
. They also have a large, accessory breathing organ composed of modified gill arches. Also, only the pectoral fins have spines.
Relationship to humans
Many of the species are of great economic importance in both fisheriesFishery
Generally, a fishery is an entity engaged in raising or harvesting fish which is determined by some authority to be a fishery. According to the FAO, a fishery is typically defined in terms of the "people involved, species or type of fish, area of water or seabed, method of fishing, class of boats,...
and fish culture
Aquaculture
Aquaculture, also known as aquafarming, is the farming of aquatic organisms such as fish, crustaceans, molluscs and aquatic plants. Aquaculture involves cultivating freshwater and saltwater populations under controlled conditions, and can be contrasted with commercial fishing, which is the...
.
Species
Species according to Ferraris, 2007 and Ng, Dang & Nguyan, 2011.African species
|
Clarias maclareni Clarias maclareni is a critically endangered species of catfish in the Clariidae family. It is endemic to Lake Barombi Mbo in western Cameroon. It is threatened because of pollution and sedimentation due to human activities, and potentially also by large emissions of carbon dioxide from the lake's... |
South Asian species
- Clarias dayi
Southeast Asian species
- Clarias anfractus Ng, 1999
- Walking catfishWalking catfishThe walking catfish, Clarias batrachus, is a species of freshwater airbreathing catfish found primarily in Southeast Asia, so named for its ability to "walk" across dry land, to find food or suitable environments...
, Clarias batrachus (Linnaeus, 1758) - Clarias batuClarias batuClarias batu is a species of clariid catfish. It is only known from Tioman Island off the eastern coast of Peninsular Malaysia. The eel-like catfish found on this island were originally identified as the widespread species Clarias nieuhofii but comparison of a large series of specimens from Tioman...
Lim & Ng, 1999 - Clarias cataractus (Fowler, 1939)
- Clarias fuscus La Cepède, 1803
- Clarias gracilentus Ng, Dang & Nguyan, 2011
- Clarias insolitus Ng, 2003
- Clarias intermedius Teugels, Pouyaud & Sudarto, 2001
- Clarias kapuasensis Sudarto, Teugels & Pouyaud, 2003
- Clarias leiacanthus Bleeker, 1851
- Broadhead catfishBroadhead catfishThe Broadhead Catfish or Clarias macrocephalus is an economically important air-breathing catfish that is a native of Southeast Asia. The fish is cultivated in fish ponds for use in human consumption in countries such as Thailand and the Philippines...
, Clarias macrocephalus Günther, 1864 - Blackskin catfish, Clarias meladerma Bleeker, 1846
- Clarias microspilus Ng & Hadiaty, 2011
- Clarias microstomus Ng, 2001
- Clarias nieuhofiiClarias nieuhofiiClarias nieuhofii is a species of clariid catfish. It has a wide distribution in Southeast Asia including peninsular Malaysia, Java, Sumatra, Borneo and the Philippines....
Valenciennes in Cuvier & Valenciennes, 1840 - Clarias nigricansClarias nigricansClarias nigricans is a species of clariid catfish. It is only known from the Mahakam River in eastern Borneo. The eel-like catfish of this region were long assumed to belong to the widespread species Clarias nieuhofii but examination of 6 specimens purchased from a fish market in Samarinda in 1999...
Ng, 2003 - Clarias olivaceus Fowler, 1904
- Clarias planiceps Ng, 1999
- Clarias pseudoleiacanthus Sudarto, Teugels & Pouyaud, 2003
- Clarias pseduonieuhofii Sudarto, Teugels & Pouyaud, 2004
- Clarias sulcatus Ng, 2004
Fossil species
- Clarias falconeri †ExtinctionIn biology and ecology, extinction is the end of an organism or of a group of organisms , normally a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point...
Lydekker, 1886, from India
Invasive species
Clarias catfish and primarely Clarias batrachus (walking catfish) has been introduced to many different areas of the world where they are causing problems for the native wildlife. The effect of introduction of clarias catfish varies from area to area but as they are predatory fish they often impact the local wildlife by eating other fishFish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...
, birds and amphibians. In Florida the fish is causing problems by invading aquaculture
Aquaculture
Aquaculture, also known as aquafarming, is the farming of aquatic organisms such as fish, crustaceans, molluscs and aquatic plants. Aquaculture involves cultivating freshwater and saltwater populations under controlled conditions, and can be contrasted with commercial fishing, which is the...
farms and prey on the fish cultivated there. Countries where one or several Clarias species have been introduced includes Indonesia
Indonesia
Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...
, USA, Hong Kong
Hong Kong
Hong Kong is one of two Special Administrative Regions of the People's Republic of China , the other being Macau. A city-state situated on China's south coast and enclosed by the Pearl River Delta and South China Sea, it is renowned for its expansive skyline and deep natural harbour...
, Taiwan
Taiwan
Taiwan , also known, especially in the past, as Formosa , is the largest island of the same-named island group of East Asia in the western Pacific Ocean and located off the southeastern coast of mainland China. The island forms over 99% of the current territory of the Republic of China following...
, China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
, UK, Papua New Guinea
Papua New Guinea
Papua New Guinea , officially the Independent State of Papua New Guinea, is a country in Oceania, occupying the eastern half of the island of New Guinea and numerous offshore islands...
, Guam
Guam
Guam is an organized, unincorporated territory of the United States located in the western Pacific Ocean. It is one of five U.S. territories with an established civilian government. Guam is listed as one of 16 Non-Self-Governing Territories by the Special Committee on Decolonization of the United...
, Taiwan
Taiwan
Taiwan , also known, especially in the past, as Formosa , is the largest island of the same-named island group of East Asia in the western Pacific Ocean and located off the southeastern coast of mainland China. The island forms over 99% of the current territory of the Republic of China following...
, Thailand
Thailand
Thailand , officially the Kingdom of Thailand , formerly known as Siam , is a country located at the centre of the Indochina peninsula and Southeast Asia. It is bordered to the north by Burma and Laos, to the east by Laos and Cambodia, to the south by the Gulf of Thailand and Malaysia, and to the...
and Cuba.