Original description as Cyprinodon fontinalis:
- Smith, Michael & R.R. Miller. 1980. "Systematics and variation of a new cyprinodontid fish, Cyprinodon fontinalis, from Chihuahua, Mexico". Proceedings of the Biological Society of Washington. 93(2):405-416 (ffm00179) (abstract)
Conservation: Cyprinodon fontinalis is evaluated by the international union for the conservation of nature in the iucn red list of threatened species as (EN) endangered (2018). Back in 2006, the spring Ojo de Agua del Apache only had little water remaining, all the other springs where Cyprinodon fontinalis was found were dried (Personal communication, Dieter Springer, Germany). It is possible that at this point C. fontinalis has become extinct in the wild. This situation gives to the long-term maintenance of the populations in captivity a special meaning.
Cyprinodon fontinalis is currently restricted to Ojo Solo, a small and failing spring system in the Samalayuca Basin, Chihuahua, Mexico. Groundwater over-extraction and surface water diversion for agricultural use threaten the persistence of suitable habitat, which has desiccated by over 70% in recent years. While conservation efforts have successfully established a secondary population at Ojo Caliente, the range and total population size of C. fontinalis are still extremely small. Given demonstrated and continuing habitat loss resulting from water resource use. The primary threat to C. fontinalis is the loss of remaining habitat as a result of groundwater extraction and surface water diversion in adjacent areas, primarily for agricultural usage. Approximately 30% of Ojo Solo remains. Additionally, the western mosquitofish (Gambusia affinis) is established in Ojo Solo, with currently unknown effects (Valdés González, 2019).