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 ...
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. 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 recognized as a natural,
monophyletic
In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria:
# the grouping contains its own most recent co ...
group based on morphological and molecular evidence. It is divided into two subfamilies, Sisorinae and Glyptosterninae (glyptosternoids). The Sisorinae contain the five genera '' Bagarius'', '' Gagata'', '' Gogangra'', '' Nangra'', and ''
Sisor
''Sisor'' is a genus of catfishes native to Asia.
Taxonomy
''Sisor'' was previously monotypic, containing only ''S. rabdophorus'', prior to a review of the genus in 2003 in which the three species ''S. chennuah'', ''S. rheophilus'', and ''S. tor ...
monophyly
In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria:
# the grouping contains its own most recent comm ...
of the entire family and the tribe Glyptosterninae are well supported by osteological morphology and molecular data.
In the genera ''Glyptothorax'' (tribe Glyptothoracini) and ''Pseudecheneis'' (tribe Pseudecheneidina), the species have thoracic adhesive apparatuses to attach to objects in the stream bed; in ''Glyptothorax'', grooves of this apparatus run parallel or oblique to the axis of the body, while in ''Pseudecheneis'' grooves run transverse to the axis of the body. The thoracic adhesive apparatus is not present in the other sisorid genera. The paired fins may be plaited to form an adhesive apparatus in ''Pseudecheneis'', glyptosternoids, and variably in ''Glyptothorax''. Thus, glyptosternoids lack a thoracic adhesive apparatus, but do have plaited paired fins, and members of the subfamily Sisorinae lack either a thoracic adhesive apparatus or plaited paired fins.
The monophyly of certain glyptosternoid genera is doubtful. The
paraphyly
Paraphyly is a taxonomic term describing a grouping that consists of the grouping's last common ancestor and some but not all of its descendant lineages. The grouping is said to be paraphyletic ''with respect to'' the excluded subgroups. In co ...
of ''Pareuchiloglanis'', ''Oreoglanis'', and ''Pseudexostoma'' (with the possible inclusion of ''Myersglanis'' and ''Parachiloglanis'') has been demonstrated and a rediagnosis of glyptosternine genera is needed.
Evidence from a 2007 molecular analysis supports
polyphyly
A polyphyletic group is an assemblage that includes organisms with mixed evolutionary origin but does not include their most recent common ancestor. The term is often applied to groups that share similar features known as homoplasies, which ar ...
of ''Pareuchiloglanis''. ''Glaridoglanis'' might be a basal member of the tribe Glyptosternina. ''Pseudecheneis'' may be placed in the tribe Glyptosternina, but its sister-group relationship between it and the monophyletic glyptosternoids cannot be rejected.
It has been proposed to move the genera of Erethistidae into Sisoridae.
Distribution
Sisorids inhabit freshwater and 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 ...
, from
Turkey
Turkey, officially the Republic of Türkiye, is a country mainly located in Anatolia in West Asia, with a relatively small part called East Thrace in Southeast Europe. It borders the Black Sea to the north; Georgia (country), Georgia, Armen ...
and
Syria
Syria, officially the Syrian Arab Republic, is a country in West Asia located in the Eastern Mediterranean and the Levant. It borders the Mediterranean Sea to the west, Turkey to Syria–Turkey border, the north, Iraq to Iraq–Syria border, t ...
to South
China
China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...
and
Borneo
Borneo () is the List of islands by area, third-largest island in the world, with an area of , and population of 23,053,723 (2020 national censuses). Situated at the geographic centre of Maritime Southeast Asia, it is one of the Greater Sunda ...
, primarily in the Oriental region. Glyptosterninae is distributed from the
Caucasus
The Caucasus () or Caucasia (), is a region spanning Eastern Europe and Western Asia. It is situated between the Black Sea and the Caspian Sea, comprising parts of Southern Russia, Georgia, Armenia, and Azerbaijan. The Caucasus Mountains, i ...
to China. Most glyptosternine genera are found in China, with the exception of ''Myersglanis''. Glyptosternoid catfish species have restricted distributions, and many apparently wide-ranging species have been shown to consist of more than one species, each with restricted distributions. Sisorids are mostly small forms inhabit mountain streams.
Fossil record and biogeography
The oldest known 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 The origin of glyptosternoid fishes could be in the later Pliocene. Another study proposes glyptosternoids possibly originated in the
Oligocene
The Oligocene ( ) is a geologic epoch (geology), epoch of the Paleogene Geologic time scale, Period that extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that defin ...
-
Miocene
The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...
boundary (19–24 Mya) and radiated from the Miocene to
Pleistocene
The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...
along with several rapid speciation events in a relatively short time. The three great uplifts of the
Qinghai
Qinghai is an inland Provinces of China, province in Northwestern China. It is the largest provinces of China, province of China (excluding autonomous regions) by area and has the third smallest population. Its capital and largest city is Xin ...
/
Tibet
Tibet (; ''Böd''; ), or Greater Tibet, is a region in the western part of East Asia, covering much of the Tibetan Plateau and spanning about . It is the homeland of the Tibetan people. Also resident on the plateau are other ethnic groups s ...
Plateau
In geology and physical geography, a plateau (; ; : plateaus or plateaux), also called a high plain or a tableland, is an area of a highland consisting of flat terrain that is raised sharply above the surrounding area on at least one side. ...
destroyed the pattern of river systems in the late Pliocene to the early Pleistocene. The ancestor of ''Euchiloglanis'' originated from the allied ''Glyptosternon'' in the second uplift and ''Pareuchiloglanis'', ''Pseudexostoma'', ''Oreoglanis'', ''Exostoma'', and ''Glaridoglanis'' originated with the third uplift. The ''Exostoma'' group (''Exostoma'', ''Pseudexostoma'', and ''Oreoglanis'') originated after the outline of the Qinghai/Tibet Plateau was formed. The speciation of this group was not strong and the distribution limited.
Description
Most of these fish have four pairs of
barbels
In fish anatomy and turtle anatomy, a barbel is a slender, whisker like sensory organ near the mouth (sometimes called whiskers or tendrils). Fish that have barbels include the catfish, the carp, the goatfish, the hagfish, the sturgeon, the z ...
and a large
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 ...
. The maximum size is 2 metres. In all fish except those of the subfamily Sisorinae, some sort of adhesive apparatus, either in the form of a thoracic adhesive apparatus or in plaited paired fins, allow the fish to adhere to objects.