Northern platyfish
The northern platyfish is a species of fish in the family Poeciliidae. It is endemic to Mexico. It was named in honor of Myron Gordon by Robert Rush Miller and W. L. Minckley who discovered it with Carl Hubbs on a 1961 expedition.
Its natural habitat is a single body of water, a hot spring heated by volcanic activity, the Laguna Santa Tecla, near the city of Cuatro Ciénegas in the Mexican state of Coahuila. Its native water is "shallow, sulphur smelling", and vegetation-choked, with water temperatures ranging from mid 80s to high 90s Fahrenheit, conditions hard to replicate in captivity. Due to canal construction at the spring, it is not known if a viable wild population survives, or if the fish has used the canals to extend its range.