Southern platyfish

Southern platyfish
Female ‘rainbow wagtail’ platy

Secure  (NatureServe)
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Cyprinodontiformes
Family: Poeciliidae
Genus: Xiphophorus
Species: X. maculatus
Binomial name
Xiphophorus maculatus
(Günther, 1866)

The southern platyfish, common platy, or moonfish (Xiphophorus maculatus) is a species of freshwater fish in family Poecilidae of order Cyprinodontiformes. A live-bearer, it is closely related to the green swordtail (X. helleri) and can interbreed with it. It is native to an area of North and Central America stretching from Veracruz, Mexico, to northern Belize.

The southern platyfish grows to a maximum overall length of 6.0 centimetres (2.4 in). Sexual dimorphism is slight, the male’s caudal fin being more pointed. The anal fin of the male fish has evolved into a gonopodium, a stick-shaped organ used for reproduction. The female southern platyfish's anal fin is fan shaped. Wild varieties are drab in coloration, lacking the distinctive dark lateral line common to many Xiphophorus species.

X. maculatus prefers slow-moving waters of canals, ditches, and warm springs. Omnivorous, its diet includes both plants and small crustaceans, insects, and annelid worms.

Breeders have developed a multitude of color varieties (e.g. orange, red, yellow, red/black, and black/white) which are common aquarium fish for hobbyists.

The southern platyfish is commonly known simply as the platy (pl. platys or platies), from the fish’s original generic name, Platypoecilus.

Nonindigenous occurrences

This species has been recorded from Orange County, California, near Westminster; near a fish farm in Conejos County and the South Platte drainage, Colorado; several counties in Florida; Hawaii; an unnamed tributary to Big Branch Bayou in Lacombe, Louisiana; Beaverhead Rock Pond (Madison County), Montana; Clark County, Nevada; and Texas. It has also been collected in the Loiza drainage near Loiza Reservoir, Quebrada Honda, and Rio Abajo Forest Station north of Utuado in Puerto Rico.

The southern platyfish has been released probably due to fish farm or aquarium releases. Specimens in Louisiana were collected near a tropical fish farm. Southern platies, and other introduced poeciliids, have been implicated in the decline of native damselflies on Oahu, Hawaii. Often the distributions of the damselflies and introduced fishes were found to be mutually exclusive, probably resulting from competition for limited insect food.

In the aquarium

Platies are easy to keep and well suited to a community aquarium. They prefer water with a 7.0–8.0 pH, a water hardness of 9.0–19.0 dGH, and a temperature range of 18–25 °C (64–77 °F).

In captivity, they reach maturity in three to four months, and breed readily, the females giving birth to about 20–40 young at a time. Often young are eaten by the adults or other inhabitants of a communal aquarium but given plants and gravel to hide in, some will probably be survive as these are hardy fish. Platy young are first seen at approx 7mm long and will use cover to hide from predators and to look for food. Specialist fry food is available but any flake food, frozen or live food that floats their way will be easily consumed. These require excellent water quality and are vulnerable to being suck up into gravel cleaning syphon. A thin membrane covering the syphon opening such a clean pair of tights will minimise this.

The fish commonly sold in pet shops is not a pure strain of X. maculatus, but is a hybrid between X. hellerii and X. maculatus. In general, if the male has a sword-shaped tail, they are called swordtails. Otherwise, they are labeled platy. Color and fin shape vary wildly in the aquarium trade.

A common statement in the trade is that it is harder to stop them breeding than to make them do so, with ‘surprise’ fry appearing in community tanks regularly.

Genetics

The genome of Xiphophorus maculatus was sequenced in 2013.[1]

References

  1. ↑ Schartl M, Walter RB, Shen Y, et al. (2013). "The genome of the platyfish, Xiphophorus maculatus, provides insights into evolutionary adaptation and several complex traits". Nature Genetics. 45 (5): 567–572. doi:10.1038/ng.2604. PMC 3677569Freely accessible. PMID 23542700.
Wikimedia Commons has media related to Xiphophorus maculatus.
This article is issued from Wikipedia - version of the 3/15/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.