Gymnocypris przewalskii

Gymnocypris przewalskii
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Cypriniformes
Family: Cyprinidae
Genus: Gymnocypris
Species: G. przewalskii
Binomial name
Gymnocypris przewalskii
(Kessler, 1876)
Synonyms

Schizopygopsis przewalskii Kessler, 1876[1]

Gymnocypris przewalskii (common name: Przewalksii's naked carp; in Chinese: 青海湖裸鲤; literally: "Qinghai Lake naked carp") is a fish found in Lake Qinghai.[2] They are planktivores that migrate to freshwater rivers to spawn.[3] The population is listed as endangered on the China Species Red List due to overfishing and habitat loss, which has led to suspension of its commercial fishery four times since 1989.[3][4][5]

Characteristics

A drawing of Gymnocypris przewalskii under the old name Schizopygopsis przewalskii

Naked carp reach a maximum length of 48 cm and are typically 300–500g at reproductive age.[2][4] They feed mostly on benthic zooplankton about 2m below the surface, though they also feed on other aquatic invertebrates.[6] They have long, flat bodies and almost no scales except near the anus and shoulder girdle, which gives them their common name. They grow relatively slowly and may take 7–10 years to reach reproductive size.[3][4]

Migration

From April to July adults migrate 40–50 km to nearby freshwater streams to spawn. These include the Harge, Goncha, Chang Ji, and Buha rivers.[7] Much like salmon, they seek sandy gravel banks with slower currents to build nests.[7] When fish return to the lake, their electrolyte levels increase quickly to concentrations similar to Lake Qinghai's salinity, while urine flow, metabolic rate, and oxygen consumption all decrease drastically.[4] This is thought to represent the reduced osmoregulatory and metabolic costs of living in Lake Qinghai which make returning after spawning and reproduction advantageous. Young fish are thought to return to the lake after overwintering in their spawning streams.[7]

References

  1. ↑ "Gymnocypris przewalskii — Synonyms Scale-less Carp: Names". Encyclopedia of Life. Retrieved 7 June 2015.
  2. 1 2 Froese, Rainer and Pauly, Daniel, eds. (2014). "Gymnocypris przewalskii" in FishBase. November 2014 version.
  3. 1 2 3 Xiong, Fei; Daqing Chen; Xinbin Duan (2010). "Threatened fishes of the world: Gymnocypris przewalskii (Kessler, 1876) (Cyprinidae: Schizothoracinae)". Environmental Biology of Fishes 87: 351–352. doi:10.1007/s10641-010-9609-x.
  4. 1 2 3 4 Wood, Chris M.; Jizeng Du; Joe Rogers; Colin J. Brauner; Jeffery W. Richards; Brent W. Murray; X.-Q. Chen; Yuxiang Wang (2007). "Przewalksii's naked carp (Gymnocypris przewalksii): An endangered species taking a metabolic holiday in Lake Qinghai, China". Physiological and Biochemical Zoology 80 (1): 59–77. doi:10.1086/509212.
  5. ↑ S. Wang, Y. Xie, ed. (2004). China Species Red List, vol 1. Beijing: Higher Education Press. p. 163.
  6. ↑ Chen, D.; Zhang, X.; Tan, X.; Wang, K.; Qiao, Y.; Chang, Y. year=2009. "Hydroacoustic study of spatial and temporal distribution of Gymnocypris przewalskii (Kessler, 1876) in Qinghai Lake, China". Environmental Biology of Fishes 84 (2): 231–239. doi:10.1007/s10641-008-9430-y.
  7. 1 2 3 Muir, James F. (1990). "Hatchery Development and Spawning Enhancement, Qinghai Lake". Fisheries Development in Qinghai Province. Food and Agricultural Organization of the United Nations. Retrieved 18 November 2012.
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