|
The Catarina pupfish (''Megupsilon aporus'') is a diminutive species of fish in the Cyprinodontidae family, first described in 1972. It was endemic to a spring in Nuevo León Mexico, but has been extinct in the wild since about 1994. As of December 2012, one small captive population still remains. In addition to its small size, it is characterized by absence of pelvic girdle and pelvic fins, and by having different numbers of chromosomes in male and female fish.〔 In 2013, its behavior was described based on very limited field observations of the previous wild population and more detailed observations in aquaria.〔 ==Conservation== The Catarina pupfish is highly imperiled. It was found in the wild in only one spring in Nuevo León Mexico together with Potosi pupfish (''Cyprinodon alvarezi''). Contreras and Lozano (1996) reported that both species had become “almost extinct” in 1994 when their spring habitat essentially dried out; however inspection of a side spring in November 1994 indicated that a few specimens remained. Subsequent publications 〔 indicated that both species had become extinct in the wild that year. The IUCN Red List also uses that designation, but cites an unpublished manuscript written earlier. Mexico’s 2010 official list of species at risk (NOM-059-SEMARNAT-2010) indicates that ''Megupsilon aporus'' is category "E" defined as "Probably extinct in the wild". Species that are considered extinct by experts are given that designation. However if a species were rediscovered alive it would be given legal protection status immediately.〔 As of December 12, 2012, a single captive population of Catarina pupfish remains. It consists of approximately 20 individuals maintained at the Children’s Aquarium at Fair Park, Dallas, Texas.〔〔(Children’s Aquarium at Fair Park Facts and Trivia ). dallaszoo.com〕 The fate of the Catarina pupfish is just one of many ongoing conservation issues in Mexico. As of 2008, approximately 40% of more than 500 described freshwater fishes in Mexico are considered to be at risk and there have been 29 extinctions mostly in the previous 50 years. The extinctions and threatened status of many freshwater fishes are associated with overexploitation, dewatering, habitat disruption, and competition with alien species of diverse sources. The inland fish fauna of Mexico is particularly vulnerable because many species (such as the Catarina pupfish) are endemic to isolated springs or small drainage systems as extensively described by Robert Rush Miller.〔Miller, Robert Rush, with the collaboration of W.L. Minckley and Steven M. Norris, and maps by Martha H. Gach (2005) ''Freshwater fishes of México'', University of Chicago Press. ISBN 9780226526041〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Catarina pupfish」の詳細全文を読む スポンサード リンク
|