Oxygymnocypris stewartii

Oxygymnocypris stewartii is a species of cyprinid fish endemic to Tibet[2] and occurs in the Yarlung Tsangpo River (=upper Brahmaputra) and its tributaries at altitudes above 3,600 m (11,800 ft) in the Qinghai-Tibet Plateau.[1][3] It is the only species in its genus.[4]

Oxygymnocypris stewartii

Near Threatened  (IUCN 3.1)[1]
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Cypriniformes
Family: Cyprinidae
Genus: Oxygymnocypris
W. H. Tsao, 1964
Species:
O. stewartii
Binomial name
Oxygymnocypris stewartii
(Lloyd, 1908)
Synonyms

Schizopygopsis stewartii Lloyd, 1908
Gymnocypris stewartii (Lloyd, 1908)

Life history and ecology

Oxygymnocypris stewartii grows to 59 cm (1.94 ft) in standard length,[3] 67.6 cm (2.22 ft) in total length and 3 kg (6.6 lb) in weight.[2] It is a long-lived (to 25 years), late-maturing species that reproduces annually.[3]

Oxygymnocypris stewartii inhabits the deeper areas of clear, fast-flowing rivers with a rocky substrate.[1] It is a generalized and opportunistic predator feeding both on fish and aquatic insects. Smaller specimens feed mostly on cobitid nemacheilid loaches and caddisflies of family Hydropsychidae, whereas larger individuals switch more towards cyprinid fishes and chironomid larvae. Triplophysa stenura is the most prevalent prey species, present in 47% of stomachs, but Schizopygopsis younghusbandi contributes most (59%) to prey weight. Insects are more important in winter and spring, and fishes in summer and autumn.[3]

Fishery

Oxygymnocypris stewartii is heavily used as a food fish and is thought to be overfished.[1]

References
  1. Ng, H.H. (2010). "Oxygymnocypris stewartii". IUCN Red List of Threatened Species. 2010: e.T168408A6487005. doi:10.2305/IUCN.UK.2010-4.RLTS.T168408A6487005.en.
  2. Froese, Rainer and Pauly, Daniel, eds. (2019). "Oxygymnocypris stewartii" in FishBase. May 2019 version.
  3. Huo, B.; Xie, C. X.; Madenjian, C. P.; Ma, B. S.; Yang, X. F.; Huang, H. P. (2014). "Feeding habits of an endemic fish, Oxygymnocypris stewartii, in the Yarlung Zangbo River in Tibet, China". Environmental Biology of Fishes. 97 (11): 1279–1293. doi:10.1007/s10641-013-0213-8.
  4. Eschmeyer, W. N. (2 June 2015). "Catalog of Fishes". California Academy of Sciences. Retrieved 8 June 2015.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.