Biology:Schizothorax

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Short description: Genus of fishes

Schizothorax
SchizothoraxPithoragarh.jpg
Schizothorax sp.
Scientific classification e
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Cypriniformes
Family: Cyprinidae
Subfamily: Barbinae
Genus: Schizothorax
Heckel, 1838
Type species
Schizothorax plagiostomus
Heckel, 1838
Synonyms

Racoma McClelland & Griffith, 1842

Schizothorax is a genus of cyprinid fish found in southern and western China, through northern South Asia (Himalaya ) and Central Asia, to Iran, with a single species, S. prophylax, in Turkey.[1][2][3] They are primarily found in highland rivers, streams and lakes, although a few species occur in lower-lying locations, like Lake Balkhash and lakes of the Sistan Basin.[1][2][4][5] Their scientific name means "cloven-breast", from Ancient Greek schízeïn (σχίζειν) 'to cleave' and thórax (θώραξ) 'breast-plate' (see also thorax). The western species are typically referred to as marinkas from their Russian name marinka (маринка), while the eastern species are usually called snowtrout. Although they do resemble trouts in habitus this is merely due to convergent evolution and they are by no means closely related apart from both being Teleostei: Cyprinids are in the teleost superorder Ostariophysi, while trouts are in the superorder Protacanthopterygii. Their ancestors must thus have diverged as early as the Triassic, more than 200 million years ago.

Schizothorax is a part of the schizothoracines (snowtrout and allies), which also includes the genera Aspiorhynchus, Chuanchia, Diptychus, Gymnodiptychus, Gymnocypris, Oxygymnocypris, Platypharodon, Ptychobarbus, Schizopyge and Schizopygopsis.[6] The last two were formerly often included in the present genus, and their delimitation is still not entirely clear. In any case, the genus Schizothorax (and other "snowtrouts") are in turn related to such cyprinids as the typical barbels (Barbus sensu stricto and the doubtfully distinct Luciobarbus and Messinobarbus), Carasobarbus, Labeobarbus, Aulopyge and Cyprinion. They were thus placed in the subfamily Barbinae, which is quite paraphyletic however and thus here merged with the Cyprininae at least for the largest part (including the marinkas), becoming its junior synonym in the process.[7]

Species

Schizothorax curvifrons
Schizothorax plagiostomus
Schizothorax waltoni

There are currently 65 recognized species in this genus:[1]

References

  1. 1.0 1.1 1.2 Froese, Rainer and Pauly, Daniel, eds. (2019). Species of Schizothorax in FishBase. May 2019 version.
  2. 2.0 2.1 Yang, J.; J.X. Yang; and X.Y. Chen (2012). A re-examination of the molecular phylogeny and biogeography of the genus Schizothorax (Teleostei: Cyprinidae) through enhanced sampling, with emphasis on the species in the Yunnan–Guizhou Plateau, China. Journal of Zoological Systematics and Evolutionary Research 50(3). doi:10.1111/j.1439-0469.2012.00661.x
  3. Coad, B.W.; and N.K.d. Ville (2004). On the systematics and distribution of the snow trout Schizothorax pelzami Kessler, 1870, in Iran (Actinopterygii: Cyprinidae). Zoology in the Middle East 32(1): 57-62. doi:10.1080/09397140.2004.10638044
  4. Hammer, U.T. (1986). Saline Lake Ecosystems of the World, p. 458. DR.W.Junk Publishers. ISBN 90-6193-535-0
  5. Coad, B.; and J. Hales (2008). Helmand - Sistan. Freshwater Ecoregions of the World. Retrieved 18 May 2019.
  6. Qi, D.; Y. Chao; S. Guo; L. Zhao; T. Li; F. Wei; and X. Zhao (2012). Convergent, Parallel and Correlated Evolution of Trophic Morphologies in the Subfamily Schizothoracinae from the Qinghai-Tibetan Plateau. PLoS ONE 7(3): e34070. doi:10.1371/journal.pone.0034070
  7. De Graaf, M.; Megens, H.-J.; Samallo, J.; Sibbing, F.A. (2007). "Evolutionary origin of Lake Tana's (Ethiopia) small Barbus species: indications of rapid ecological divergence and speciation". Animal Biology 57 (1): 39–48. doi:10.1163/157075607780002069. 
  8. Arunkumar, L. & Alphonsa Moyon, W. (2016): Schizothorax chivae, a new schizothoracid fish from Chindwin basin, Manipur, India (Teleostei: Cyprinidae). International Journal of Fauna and Biological Studies, 3 (2): 65-70.
  9. 9.0 9.1 Yang, J., Zheng, L.-P., Chen, X.-Y. & Yang, J.-X. (2013): Description of two new species and revision of Schizothorax distributed in the Irrawaddy drainage area in China. Zoological Research, 34 (4): 361-367.
  10. Javed, M.N., Azizullah & Pervaiz, K. (2012): Racoma ramzani, A New Snow Carp (Teleostei: Cyprinidae: Schizothoracinae) From Pakistan. Biologia (Pakistan), 58 (1-2): 175-178.

Wikidata ☰ Q310753 entry