Monterrey platyfish
{{Short description|Species of fish}}
{{Speciesbox
| name = Monterrey platyfish
| image = 016776F000199W000002.jpg
| status = EW
| status_system = IUCN3.1
| taxon = Xiphophorus couchianus
| authority = (Girard, 1859)
| synonyms = *Limia couchiana Girard, 1859
- Platypoecilus couchianus (Girard, 1859)
- Poecilia couchii Günther, 1866
}}
The Monterrey platyfish (Xiphophorus couchianus) is a species of freshwater fish in family Poecilidae. A live-bearer, it was native to a very small section of the San Juan River system (itself part of the Rio Grande basin) in the vicinity of the city of Monterrey, Mexico.{{FishBase|genus=Xiphophorus|species=couchianus|year=2018|month=September}}{{cite book | editor1=Ceballos, G. | editor2=E.D. Pardo | editor3=L.M Estévez | editor4=H.E. Pérez | year=2016 | title=Los peces dulceacuícolas de México en peligro de extinción | pages=48, 280 | publisher=Fondo de Cultura Económic | isbn=978-607-16-4087-1 }} The specific name refers to the American soldier and naturalist Darius N. Couch (1822–1897) who collected the type on a self-financed expedition to Mexico.{{cite web | url = http://www.etyfish.org/cyprinodontiformes4/ | work = The ETYFish Project Fish Name Etymology Database | author1 = Christopher Scharpf | author2 = Kenneth J. Lazara | date = 26 October 2019 | title= Order CYPRINODONTIFORMES: Families POECILIIDAE, ANABLEPIDAE, VALENCIIDAE, APHANIIDAE and PROCATOPODIDAE | access-date = 9 November 2019 | publisher = Christopher Scharpf and Kenneth J. Lazara}}
Appearance
The Monterrey platyfish is a dull-colored fish, appearing not unlike a female guppy. Another form, sometimes referred to as X. aff. couchianus, was discovered in Apodaca, central Monterrey, in 1983. It has large black blotching, unlike the typical, unspotted form from the Huasteca Canyon. Whether the Apodaca form represents a separate species is presently unclear.{{cite web | author=Coletti, T. | date=December 2007 | url=http://www.tfhmagazine.com/details/articles/preserving-xiphophorus-couchianus-in-the-home-aquarium-part-i-sad-history-unanswered-questions.htm |title=Preserving Xiphophorus couchianus in the Home Aquarium, Part I: Sad History & Unanswered Questions | publisher=tfhmagazine.com |access-date=23 September 2018 }}{{cite journal | author1=Kallman, K.D. | author2=S. Kazianis | year=2006 | title=The genus Xiphophorus in Mexico and Central America | journal=Zebrafish | volume=3 | issue=3 | pages=271–285 | doi=10.1089/zeb.2006.3.271 | pmid=18377209 }}
Sexual dimorphism is moderate, the male Monterrey platyfish growing to a maximum overall length of {{cvt|4|cm|in}} and the female {{cvt|6|cm|in}}.
Conservation
IUCN lists the Monterrey platyfish as "extinct in the wild". Although once found more widely in the region of Monterrey, populations have been lost to urban sprawl, with water habitats either drying up (due to land reclamation and water extraction) or being heavily polluted. Introduced species is another threat. "Safety populations" are maintained in captivity by the Centro de Resguardo para Peces en Peligro de Extinción at Universidad Autónoma de Nuevo León, Mexico (maintaining both the typical form and X. aff. couchianus), Xiphophorus Genetic Stock Center at Texas State University, United States (maintaining typical form), via the American Livebearer Association that mostly includes private aquarists in the United States (maintaining typical form), and by XNP conservation project members, which include public aquariums, universities and private aquarists in several European countries and the United States (maintaining typical form).{{cite web| title=XNP project annual report – year 3 | url=https://oevvoe.org/xnp-project-annual-report-%E2%80%93-year-3 | publisher=Österreichischen Verband für Vivaristik und Ökologie | accessdate=17 January 2022 }}{{cite web| title=XNP project expanding | url=https://oevvoe.org/xnp-project-expanding | publisher=Österreichischen Verband für Vivaristik und Ökologie | accessdate=17 January 2022 }} The species has proven harder to maintain in captivity than most Xiphophorus species.
The Monterrey platyfish shares the title as northernmost naturally distributed Xiphophorus with the closely related northern platyfish (X. gordoni) and marbled swordtail (X. meyeri), which are two species that also are restricted to northeastern Mexico and seriously threatened.{{cite journal | author1=Kang, J.H. | author2=M. Schartl | author3=R.B. Walter | author4=A. Meyer | year=2013 | title=Comprehensive phylogenetic analysis of all species of swordtails and platies (Pisces: Genus Xiphophorus) uncovers a hybrid origin of a swordtail fish, Xiphophorus monticolus, and demonstrates that the sexually selected sword originated in the ancestral lineage of the genus, but was lost again secondarily | journal=BMC Evolutionary Biology | volume=13 | issue=25 | pages=25 | doi=10.1186/1471-2148-13-25 | pmid=23360326 | pmc=3585855 | doi-access=free | bibcode=2013BMCEE..13...25K }}
References
{{Reflist}}
- {{ITIS |id=647737 |taxon=Xiphophorus couchianus |accessdate=9 December 2004}}
{{Taxonbar|from=Q2170401}}
Category:Freshwater fish of Mexico
Category:Fish described in 1859