HomeFish encyclopediaRay-finned fishesLive bearers, Killifishes and RivulinesPoeciliidsHeadwater livebearer Headwater livebearer (Poeciliopsis monacha) Scientific name: Poeciliopsis monacha Miller, 1960 The Headwater livebearer (Poeciliopsis monacha) is a freshwater fish of the family Poeciliidae. Native range: Central America, Mexico. Species factsScientific namePoeciliopsis monachaFamilyPoeciliidae (Poeciliids)OrderCyprinodontiformes (Live bearers, Killifishes and Rivulines)ClassActinopterygii (Ray-finned fishes)EnvironmentFreshwater; benthopelagic; non-migratoryClimateTropicalDistributionCentral America: Mexico.Conservation status (IUCN)Data deficient (DD)Threat 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