HomeFish encyclopediaRay-finned fishesLive bearers, Killifishes and RivulinesPoeciliidsSheepshead swordtail Sheepshead swordtail (Xiphophorus birchmanni) Scientific name: Xiphophorus birchmanni Lechner & Radda, 1987 The Sheepshead swordtail (Xiphophorus birchmanni) is a freshwater fish of the family Poeciliidae. In the aquarium it needs water at 24–28°C (75–82°F). Native range: Central America, Rio Panuco basin in Hidalgo, Mexico. Sheepshead swordtail care at a glanceTemperature24–28°C (75–82°F) Species factsScientific nameXiphophorus birchmanniFamilyPoeciliidae (Poeciliids)OrderCyprinodontiformes (Live bearers, Killifishes and Rivulines)ClassActinopterygii (Ray-finned fishes)Maximum length7.0EnvironmentFreshwater;; pH range: 7.2 - 8.2; dH range: 5 - 20 benthopelagicClimateTropicalDistributionCentral America: Rio Panuco basin in Hidalgo, Mexico.Conservation status (IUCN)Not EvaluatedThreat to humansHarmlessResilienceHigh, minimum population doubling time less than 15 months (Preliminary K or Fecundity.) SourcesTaxonomy, distribution and biology data: FishBase (Froese, R. and D. Pauly, eds.), licensed CC BY-NC 4.0.Last updated 27 September 2026