The Maya pupfish (''Cyprinodon maya''), known in

Spanish Spanish might refer to: * Items from or related to Spain: **Spaniards are a nation and ethnic group indigenous to Spain **Spanish language, spoken in Spain and many Latin American countries **Spanish cuisine Other places * Spanish, Ontario, Cana ...

as ''cachorrito gigante'', is a highly

threatened Threatened species are any species (including animals, plants and fungi) which are vulnerable to endangerment in the near future. Species that are threatened are sometimes characterised by the population dynamics measure of ''critical depensat ...

species of

fish Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of li ...

in the family Cyprinodontidae. It is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

Lake Chichancanab Lake Chichancanab is a lake in Mexico located in the northwest of the state of Quintana Roo, in the municipality of José María Morelos. It is also known as Laguna Chichancanab, Laguna Chicnancanab and Laguna de Chichancanab. It has an approxim ...

Quintana Roo Quintana Roo ( , ), officially the Free and Sovereign State of Quintana Roo ( es, Estado Libre y Soberano de Quintana Roo), is one of the 31 states which, with Mexico City, constitute the 32 federal entities of Mexico. It is divided into 11 mu ...

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

. In almost all places, different ''

Cyprinodon ''Cyprinodon'' is a genus of pupfishes found in waters that range from fresh to hypersaline. The genus is primarily found in Mexico, the Caribbean Islands and southern United States (Arizona, California, Florida, Nevada, New Mexico, Oklahoma and ...

'' species do not overlap in their range, but there are two notable exceptions and one of these is Lake Chichancanab, which is inhabited by ''C. maya'', '' C. beltrani'', '' C. esconditus'', '' C. labiosus'', '' C. simus'', '' C. suavium'' and '' C. verecundus'' (the other place where several ''Cyprinodon'' species live together are lakes in

San Salvador Island San Salvador Island (known as Watling's Island from the 1680s until 1925) is an island and district of The Bahamas. It is widely believed that during Christopher Columbus's first expedition to the New World, this island was the first land he s ...

, the Bahamas). Living together, the ''Cyprinodon'' species in Lake Chichancanab have diverged into different niches. Pupfish typically feed on algae and

detritus In biology, detritus () is dead particulate organic material, as distinguished from dissolved organic material. Detritus typically includes the bodies or fragments of bodies of dead organisms, and fecal material. Detritus typically hosts commun ...

. In Lake Chichancanab, however, ''C. maya'' has become not only the largest species in the genus ''Cyprinodon'', up to long, but also the only that catches and eats whole fish ('' C. desquamator'' of San Salvador Island is a

scale-eater Lepidophagy is a specialised feeding behaviour in fish that involves eating the scales of other fish. Lepidophagy is widespread, having evolved independently in at least five freshwater families and seven marine families. A related feeding beh ...

). In smaller quantities it eats

ostracod Ostracods, or ostracodes, are a class of the Crustacea (class Ostracoda), sometimes known as seed shrimp. Some 70,000 species (only 13,000 of which are extant) have been identified, grouped into several orders. They are small crustaceans, typic ...

s and

freshwater snail Freshwater snails are gastropod mollusks which live in fresh water. There are many different families. They are found throughout the world in various habitats, ranging from ephemeral pools to the largest lakes, and from small seeps and springs ...

s. Among the endemic ''Cyprinodon'' species in Lake Chichancanab, only ''C. beltrani'' and ''C. labiosus'' still occur in some numbers in their habitat, while the remaining are virtually—if not fully—

extinct in the wild A species that is extinct in the wild (EW) is one that has been categorized by the International Union for Conservation of Nature as known only by living members kept in captivity or as a naturalized population outside its historic range due ...

. At least some of these, including ''C. maya'', survive in captivity. The primary reason for their decline is

introduced species An introduced species, alien species, exotic species, adventive species, immigrant species, foreign species, non-indigenous species, or non-native species is a species living outside its native distributional range, but which has arrived there ...

, notably the

Nile tilapia The Nile tilapia (''Oreochromis niloticus'') is a species of tilapia, a cichlid fish native to the northern half of Africa and the Levante area, including Israel, and Lebanon. Numerous introduced populations exist outside its natural range. It i ...

and the

tetra Terrestrial Trunked Radio (TETRA; formerly known as Trans-European Trunked Radio), a European standard for a trunked radio system, is a professional mobile radio and two-way transceiver specification. TETRA was specifically designed for use by go ...

Astyanax fasciatus In Greek mythology, Astyanax (; grc, Ἀστυάναξ ''Astyánax'', "lord of the city") was the son of Hector, the crown prince of Troy, and his wife, Princess Andromache of Cilician Thebe."Astyanax". ''Oxford Classical Dictionary''. Oxford, 1 ...

''.

References

Maya pupfish Endemic fish of Mexico Freshwater fish of Mexico Endangered fish Endangered biota of Mexico Taxa named by Julian M. Humphries Taxa named by Robert Rush Miller Fish described in 1981 Taxonomy articles created by Polbot {{Cyprinodontiformes-stub