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.
The sailfin molly is a livebearer fish typically found in both freshwater and brackish waterways along the East Coast of the United States, from North Carolina south to Florida, and around the Gulf of Mexico to Texas, and south to the Yucatán Peninsula of México. Given their preference for more brackish water conditions, mollies are often found within just a few yards or miles of the ocean, inhabiting coastal estuaries, lagoons, river deltas and swamps, as well as tidal areas with a regular inflow of oceanic minerals and nutrients mixing with inland freshwater sources.
The widemouth gambusia is a species of fish in the family Poeciliidae of the order Cyprinodontiformes. It is endemic to Mexico, specifically to the Baños del Azufre near Teapa, Tabasco. The Baños del Azufre are sulfidic springs that contain high concentrations of toxic hydrogen sulfide. This prevents most animals from living in them; the only other fish found in the toxic sections of Baños del Azufre is the sulphur molly.
Poecilia sphenops, called the short-finned molly or common molly, is a poeciliid fish inhabiting freshwater streams, coastal brackish, and marine waters from Mexico to Colombia. The wild-type fishes are dull, silvery in color. The molly can produce fertile hybrids with many Poecilia species, most importantly the sailfin molly. The male mollies generally tend to be mildly aggressive.
Eleotridae is a family of fish commonly known as sleeper gobies, with about 34 genera and 180 species. Most species are found in the tropical Indo-Pacific region, but there are also species in subtropical and temperate regions, warmer parts of the Americas and near the Atlantic coast in Africa. While many eleotrids pass through a planktonic stage in the sea and some spend their entire lives in the sea; as adults, the majority live in freshwater streams and brackish water. One of its genera, Caecieleotris, is troglobitic. They are especially important as predators in the freshwater stream ecosystems on oceanic islands such as New Zealand and Hawaii that otherwise lack the predatory fish families typical of nearby continents, such as catfish. Anatomically, they are similar to the gobies (Gobiidae), though unlike the majority of gobies, they do not have a pelvic sucker.
Euryhaline organisms are able to adapt to a wide range of salinities. An example of a euryhaline fish is the short-finned molly, Poecilia sphenops, which can live in fresh water, brackish water, or salt water.
The Amazon molly is a freshwater fish native to warm, fresh waters between Tuxpan River in northeastern Mexico and the Rio Grande and the Nueces River in the southern parts of the U.S. state of Texas. It reproduces through gynogenesis, and essentially all individuals are females. The common name of "Amazon molly," acknowledges this trait as a reference to the Amazon warriors, a female-run society in Greek mythology.
The New Zealand longfin eel, also known as ōrea, is a species of freshwater eel that is endemic to New Zealand. It is the largest freshwater eel in New Zealand and the only endemic species – the other eels found in New Zealand are the native shortfin eel, also found in Australia, and the naturally introduced Australian longfin eel. Longfin eels are long-lived, migrating to the Pacific Ocean near Tonga to breed at the end of their lives. They are good climbers as juveniles and so are found in streams and lakes a long way inland. An important traditional food source for Māori, who name them ōrea, longfin eel numbers are declining and they are classified as endangered, but over one hundred tonnes are still commercially fished each year.
Poecilia velifera, known as the Yucatan molly and also as the giant sailfin molly amongst aquarists, is a large livebearer that lives in coastal waters of the Yucatan Peninsula. These live-bearer (Poeciliidae) fish are particularly well known for both the extreme size variation among males, and the sexual dimorphism between males and females in both body shape and behavior.
The twait shad or twaite shad is a species of fish in the family Alosidae. It is found in the eastern Atlantic Ocean and the Mediterranean Sea and is an anadromous fish which lives in the sea but migrates into fresh water to spawn. In appearance it resembles an Atlantic herring but has a row of six to ten distinctive spots on its silvery flanks. They become mature when three or more years old and migrate to estuaries, later swimming up rivers to spawn. Populations of this fish have declined due to overfishing, pollution and habitat destruction. Conservation of this species is covered by Appendix III of the Bern Convention and Appendix II and V of the European Community Habitats Directive.
The sulphur molly, locally known as molly del Teapa, is an endangered species of fish in the family Poeciliidae. It is endemic to Mexico, specifically to the Baños del Azufre near Teapa, Tabasco. The Baños del Azufre are sulfidic springs that contain high concentrations of toxic hydrogen sulfide. Poecilia sulphuraria has apparently evolved the ability to tolerate the toxic conditions. A few other Poecilia species are known from similar habitats in Mexico.
Microphis lineatus, the opossum pipefish, is a species of fish in the family Syngnathidae. It is found in fresh, brackish and marine waters in the West Atlantic region, ranging from New Jersey, United States, to São Paulo, Brazil, including the Caribbean and Gulf of Mexico. It is often found in rivers, among water hyacinth roots, in mangrove and in Sargassum.
Cavefish or cave fish is a generic term for fresh and brackish water fish adapted to life in caves and other underground habitats. Related terms are subterranean fish, troglomorphic fish, troglobitic fish, stygobitic fish, phreatic fish, and hypogean fish.
Illex illecebrosus, commonly known as the northern shortfin squid, is a species of neritic squids in the family Ommastrephidae. Squids of the genus Illex account for 65% of the world's cephalopod captures. Illex is formed by four taxa distributed throughout the Atlantic Ocean, whose identification and phylogenetic relationships based on morphological characters remain controversial.They are found in the northwest Atlantic Ocean, from off the coast of eastern North America to Greenland, Iceland, and west of Ireland and the United Kingdom. They are a highly migratory and short-lived species, with lifespans of less than a year. They are commercially important and are fished extensively, mostly for the Canadian and Japanese markets.
Zoogoneticus tequila, Tequila splitfin or simply Tequila fish, is a species of goodeid fish from Mexico. The specific epithet, tequila, derives from the Tequila Volcano, which looms near the type locality.
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.
Poecilia gillii, Gill's molly, is a herbivorous livebearer fish distributed throughout Central America. It is found in both moving and still water as well as in both freshwater and brackish habitats. Populations of this species differ in color, size, and morphology.
Poecilia vivipara, sometimes called the southern molly, is a small euryhaline livebearer fish distributed along the Atlantic coast of South America. It is most frequently found in standing brackish water. It has been introduced outside its native range to control mosquito populations and is occasionally kept in home aquariums.
Poecilia orri, the mangrove molly, is a brackish-water livebearer fish from Central America. Two morphs exist, differing in size, body shape, and coloring.
Poecilia vandepolli, or Vandepoll's molly, is a poeciliid fish native to the Lesser Antilles. A euryhaline species, it is one of the most common fish in its range, inhabiting fresh, brackish, salt, and hypersaline waters. The fish vary significantly in size and color.
