Yunnanilus discoloris

Yunnanilus discoloris is a species of ray-finned fish, a stone loach, in the genus Yunnanilus. It is currently only in a single spring in the drainage basin of Lake Dianchi in Yunnan.

Yunnanilus discoloris
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Cypriniformes
Family: Nemacheilidae
Genus: Yunnanilus
Species:
Y. discoloris
Binomial name
Yunnanilus discoloris
W. Zhou & J. C. He, 1989[2]

Description

Yunnanilus discoloris is so named because of the sexual dimorphism this species shows. The specific name discoloris means differently cloured, it refers to the sexually dimorphic colour pattern. The males have a black longitudinal stripe on both flanks with a light blackish stripe of spots along its back while the female shows black spotting and blotching on both the back and the flanks.[3] It is a dwarf species which has a scaleless body and the origin of the dorsal fin is in halfway along the body.[4]

Habitat and distribution

It is restricted to one tributary spring, the White Dragon Spring near Chenggong in Kunming, which flows into Lake Dianchi in Yunnan, southern China. The water in the spring, which lies at 1,886m above sea level, is clear with a bed consisting of sand with some stones and with a plant community made up of Ceratophyllum demersum, Spirogyra spp. and other species of macrophytes growing on the substrate.[1]

Conservation

Yunnanilus discoloris has a very restricted range, the single spring in which it occurs contains introduced species and the spring has been modified by man. The spring is not protected and the IUCN assess the status of this species as Critically Endangered.[1] There may be 500 individuals in the White Dragon Spring. It formerly occurred in Lake Dianchi but its extirpation from there is thought to have been the result of the introduction of black carp, grass carp, silver carp and bighead carp into the lake, as well as pollution and the resultant loss of macrophytes.[4]

References
  1. Chen, X.-Y.; Jiang, Y.-E. (2008). "Yunnanilus discoloris". The IUCN Red List of Threatened Species. 2008: e.T135150A4067454. doi:10.2305/IUCN.UK.2008.RLTS.T135150A4067454.en. Downloaded on 25 January 2018.
  2. Froese, Rainer and Pauly, Daniel, eds. (2017). "Yunnanilus discoloris" in FishBase. October 2017 version.
  3. Kottelat, M. (2012). "Conspectus_cobitidum.pdf Conspectus cobitidum: an inventory of the loaches of the world (Teleostei: Cypriniformes: Cobitoidei)" (PDF). The Raffles Bulletin of Zoology. Supplement No. 26: 1–199.
  4. Yan E. Jiang; Xiao-Yong Chen; Jun_Ying Yang (2009). "Threatened Fishes of the World Yunnanilus discoloris Zhou & He 1989 (Cobitidae)". In David L.G. Noakes; Aldemaro Romero; Yahui Zhao; Yingqi Zhou (eds.). Chinese Fishes Volume 28 of Developments in Environmental Biology of Fishes. Springer Science & Business Media. ISBN 9048134587.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.