''Bagarius rutilus'' is a
species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriat ...
of
sisorid catfish native to
Laos
Laos (, ''Lāo'' )), officially the Lao People's Democratic Republic ( Lao: ສາທາລະນະລັດ ປະຊາທິປະໄຕ ປະຊາຊົນລາວ, French: République démocratique populaire lao), is a socialist s ...
,
Vietnam
Vietnam or Viet Nam ( vi, Việt Nam, ), officially the Socialist Republic of Vietnam,., group="n" is a country in Southeast Asia, at the eastern edge of mainland Southeast Asia, with an area of and population of 96 million, making ...
and
Yunnan
Yunnan , () is a landlocked province in the southwest of the People's Republic of China. The province spans approximately and has a population of 48.3 million (as of 2018). The capital of the province is Kunming. The province borders the ...
in
China
China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's List of countries and dependencies by population, most populous country, with a Population of China, population exceeding 1.4 billion, slig ...
where it is found in the
Nam Sam
Nam, Nam, or The Nam are shortened terms for:
* Vietnam, which is also spelled ''Viet Nam''
* The Vietnam War
Nam, The Nam or NAM may also refer to:
Arts and media
* Nam, a fictional character in anime series ''Dragon Ball''
* ''NAM'' (vide ...
,
Nam Ma and
Red River basins.
Description
Small fish over 15 cm eat aquatic larvae and insects including mayflies, caddisflies
The caddisflies, or order Trichoptera, are a group of insects with aquatic larvae and terrestrial adults. There are approximately 14,500 described species, most of which can be divided into the suborders Integripalpia and Annulipalpia on the ...
, hemiptera
Hemiptera (; ) is an order of insects, commonly called true bugs, comprising over 80,000 species within groups such as the cicadas, aphids, planthoppers, leafhoppers, assassin bugs, bed bugs, and shield bugs. They range in size from to arou ...
, beetles
Beetles are insects that form the order Coleoptera (), in the superorder Endopterygota. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 400,000 describe ...
, odonata
Odonata is an order of flying insects that includes the dragonflies and damselflies. Members of the group first appeared during the Triassic, though members of their total group, Odonatoptera, first appeared in Late Carboniferous.
The two com ...
, shrimp and juvenile fish while mature fish eat other fish. It congregates where there are other fish especially fish breeding grounds. This species breeds from March or June or later and they migrate to upper and middle parts of rivers and streams. Eggs are laid in stone niches and are rather large with measures 1.1 mm to 1.4 mm.
Threats and status
It is threatened by overfishing and habitat loss such as dam construction; for example the species may have been affected by the construction of Trung Sơn Dam. The species is thought to have declined 20% in many areas because of dam construction for irrigation and hydroelectricity but further studies are needed. It is caught by fisheries and is of high economic value. Severe fishing exploitation happens from December to May in high production places such Red River. It is considered Vulnerable in Vietnam and IUCN says although this species could actually be Near Threatened, it is listed as Data Deficient due to lack of information.
References
Sisoridae
Catfish of Asia
Freshwater fish of China
Fish of Laos
Fish of Vietnam
Fish described in 2000
{{Siluriformes-stub