Poeciliidae are a family of freshwater ray-finned fishes of the order Cyprinodontiformes, the tooth-carps, and include well-known live-bearing aquarium fish, such as the guppy, molly, platy, and swordtail. The original distribution of the family was the Southeastern United States to north of Río de la Plata, Argentina, and Africa, including Madagascar. Due to release of aquarium specimens and the widespread use of species of the genera Poecilia and Gambusia for mosquito control, though, poeciliids can today be found in all tropical and subtropical areas of the world. In addition, Poecilia and Gambusia specimens have been identified in hot springs pools as far north as Banff, Alberta.
Gambusia is a large genus of viviparous fish in the family Poeciliidae. Gambusia contains over 40 species, most of which are principally found in freshwater habitats, though some species may also be found in brackish or saltwater habitats. The genus Gambusia comes from the Cuban term, "Gambusino", which means "free-lance miner". The type species is the Cuban gambusia, G. punctata. The greatest species richness is in Mexico, Texas, and the Greater Antilles, but species are also found elsewhere in the eastern and southern United States, the Bahamas, Central America, and Colombia. Gambusia species are often called topminnows, or simply gambusias; they are also known as mosquitofish, which, however, refers more specifically to two species, G. affinis and G. holbrooki, which are often introduced into ponds to eat mosquito larvae. As a consequence, they have been introduced widely outside their native range, and frequently become invasive, threatening local species. G. affinis and G. holbrooki are now established in many parts of the world and are likely to continue to spread as climatic conditions change. They are only occasionally kept in aquariums, due to their relative lack of color and the highly aggressive nature of the aforementioned mosquitofish species.
Xiphophorus is a genus of euryhaline and freshwater fishes in the family Poeciliidae of order Cyprinodontiformes, native to Mexico and northern Central America. Xiphophorus species can be divided into 3 groups based on their evolutionary relationships: platyfish, northern swordtails, and southern swordtails. Platyfish formerly were classified in another genus, Platypoecilus, which is now obsolete. The type species is X. hellerii, the green swordtail. Like most other new world Poeciliids, platies and swordtails are live-bearers that use internal fertilization and give birth to live young instead of laying eggs like the bulk of the world's fishes. The name Xiphophorus derives from the Greek words ξίφος (dagger) and φόρος (bearer), referring to the gonopodium on the males. All are relatively small fishes, which reach a maximum length of 3.5–16 cm (1.4–6.3 in) depending on the exact species involved.
Poecilia is a genus of fishes in the family Poeciliidae of the order Cyprinodontiformes. These livebearers are native to fresh, brackish and salt water in the Americas, and some species in the genus are euryhaline. A few have adapted to living in waters that contain high levels of toxic hydrogen sulfide and a population of P. mexicana lives in caves.
Aulonocara is a genus of haplochromine cichlids endemic to Lake Malawi in East Africa. All Aulonocara species are maternal mouth brooders. Particularly in the aquarium hobby, Aulonocara species are also known as peacock cichlids, aulonocaras or simply "peacocks". This genus is strongly sexually dichromic, even by haplochromine standards.
Laguna Catemaco is a freshwater lake located at the center of the Sierra de Los Tuxtlas in south central Veracruz near the city of Catemaco, in east central Mexico.
Fundulus is a genus of ray-finned fishes in the superfamily Funduloidea, family Fundulidae. It belongs to the order of toothcarps (Cyprinodontiformes), and therein the large suborder Cyprinodontoidei. Most of its closest living relatives are egg-laying, with the notable exception of the splitfin livebearers (Goodeidae).
Catostomus is a genus of fish belonging to the family Catostomidae, commonly known as suckers. This genus of fish usually lives in freshwater basins. Most members of the genus are native to North America, but C. catostomus is also found in Russia.
Notropis is a genus of freshwater fish in the family Cyprinidae. They are known commonly as eastern shiners. They are native to North America, and are the continent's second largest genus.
Cyprinella is a genus of fish in the family Cyprinidae, the carps and minnows. They are known as the satinfin shiners. They are native to North America, and some are among the most common freshwater fish species on the eastern side of the continent. Conversely, several Cyprinella species with small distributions are threatened and the Maravillas Creek subspecies of the red shiner is extinct.
Allotoca is a genus of splitfins that are endemic to west-central and southwest Mexico, where restricted to the Lerna–Chapala–Grande de Santiago, Ameca and Balsas river basins, as well as various endorheic lake basins in Michoacán and Jalisco. All Allotoca species are seriously threatened.
Girardinichthys is a genus of splitfins that are endemic to Mexico. These highly threatened fish are native to the upper Lerma and Balsas basins, as well as water systems in the Valley of Mexico. Through man-made channels G. viviparus has been able to spread to the upper Pánuco River basin. These small fish reach up to 6.5 cm (2.6 in) in length. The name of this genus honours the American herpetologist and ichthyologist Charles Girard (1822-1895).
Poeciliopsis monacha, or the headwater livebearer, is a species of freshwater fish in the family Poeciliidae. It is endemic to Mexico.
Heterandria is a genus of livebearing fishes within the family Poeciliidae. Most species occur in Guatemala and its surroundings, particularly Mexico, but the midget livebearer (H. formosa) comes from the southeastern United States.
The Yaqui topminnow is a species of fish in the family Poeciliidae. Its scientific name is Poeciliopsis sonoriensis; it is also sometimes considered a subspecies of Poeciliopsis occidentalis as P. o. sonoriensis. This fish is native to Mexico and the United States, with a few native and introduced populations persisting in Arizona in the United States, and a number of populations still extant in northern Sonora, Mexico.
Profundulus is a genus of fish in the family Profundulidae endemic to Mexico and northern Central America. It was regarded as the only genus in the Profundulidae but workers have split the genus and raised a second genus Tlaloc.
Atherinella is a genus of Neotropical silversides from freshwater, brackish and marine habitats in Mexico, Central America and South America.
Poeciliinae is a subfamily of killifish from the family Poeciliidae which contains species from the Americas which are collectively known as the livebearers because many, but not all, of the species within the subfamily are ovoviviparous.
Xiphophorus milleri, the Catemaco platyfish, is a poeciliid fish endemic to Mexico's Lake Catemaco and its tributaries. As it has traits of both swordtails and platies, its discovery confirmed that these two groups should be consolidated into a single genus, Xiphophorus.
Poecilia kykesis, also known as the Usumacinta molly, Petén molly, spiketail molly, or swordtail molly, is a poeciliid fish species native to the fresh and brackish waters of Mexico, Guatemala, and Belize. It belongs to the sailfin molly clade, with males exhibiting an enlarged dorsal fin. The species has a notably controversial naming history, with the former name, Poecilia petenensis, now referring to a short-finned molly species. It is a livebearer sometimes kept in aquaria.
