Erethistidae are a family of

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 that originate from southern

Asia Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which ...

. It includes about 45 species.

Taxonomy

This family includes species previously placed in

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 ...

. They were removed because they were thought to be more closely related to the neotropical

Aspredinidae The Aspredinidae are a small South American family (biology), family of catfishes (order (biology), order Siluriformes) also known as the banjo catfishes, with about 43 species. Distribution Aspredinids are found throughout the major tropical ri ...

than to the remaining sisorids due to a number of morphological characters. However, it has been suggested that the erethistid catfishes be included back into Sisoridae and some genera are included in that family by some authorities.

Distribution

Erethistids are found on the

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 ...

n subcontinent eastwards to western

Thailand Thailand, officially the Kingdom of Thailand and historically known as Siam (the official name until 1939), is a country in Southeast Asia on the Mainland Southeast Asia, Indochinese Peninsula. With a population of almost 66 million, it spa ...

and northern

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 ...

Description

Many of the members of this family are small, cryptically colored fish with tuberculate skin. Erethistids are distinguished from sisorids by having a

pectoral girdle The shoulder girdle or pectoral girdle is the set of bones in the appendicular skeleton which connects to the arm on each side. In humans, it consists of the clavicle and scapula; in those species with three bones in the shoulder, it consists o ...

with a long

coracoid A coracoid is a paired bone which is part of the shoulder assembly in all vertebrates except therian mammals (marsupials and placentals). In therian mammals (including humans), a coracoid process is present as part of the scapula, but this is n ...

process that extends well beyond the base of the

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 ...

; this structure can be felt through the skin in all genera and is visible externally in all genera except ''

Pseudolaguvia ''Pseudolaguvia'' is a genus of South Asian river catfishes. These species inhabit hill streams and large rivers. '' P. tenebricosa'' is found in fast running, clear water; the river has a sandy bottom and numerous rocks and boulders and aquatic ...

''. Erethistids differ from amblicipitids in that they lack a cuplike fold of skin in front of the pectoral fin (vs. possessing the cuplike fold) and have a dorsal fin with a strong spine and no thick covering of skin (vs. a weak spine with a thick covering of skin). Erethistids have nostrils close together, separated by a nasal

barbel Barbel may refer to: *Barbel (anatomy), a whisker-like organ near the mouth found in some fish (notably catfish, loaches and cyprinids) and turtles *Barbel (fish), a common name for certain species of fish **''Barbus barbus'', a species of cyprini ...

, which differs from akysids which have widely separated nostrils on each side of the head with a barbel on the posterior nostril. Some erethistids possess a

thoracic The thorax (: thoraces or thoraxes) or chest is a part of the anatomy of mammals and other tetrapod animals located between the neck and the abdomen. In insects, crustaceans, and the extinct trilobites, the thorax is one of the three main ...

adhesive Adhesive, also known as glue, cement, mucilage, or paste, is any non-metallic substance applied to one or both surfaces of two separate items that binds them together and resists their separation. The use of adhesives offers certain advantage ...

apparatus formed by longitudinal skin folds densely covered with unculi that appears to be an adaptation to life in fast-flowing waters; this closely resembles a similar structure in the sisorid ''

Glyptothorax ''Glyptothorax'' is a genus of catfishes order Siluriformes of the family Sisoridae. It is the most species-rich and widely distributed genus in the family with new species being discovered on a regular basis. These species are distributed in t ...

''.

References

{{Taxonbar, from=Q141902 Catfish families Fish of South Asia Taxa named by Pieter Bleeker