Limia

''Limia'' is a genus of livebearing fishes belonging to the Cyprinodontiform family Poeciliidae, which includes other livebearers such as platys, swordtails (genus ''Xiphophorous''), guppies and mollies (genus ''Poecilia''). They are found in fresh and brackish water. Of the 21 described ''Limia'' species, 17 are endemic to Hispaniola, one is found on both Hispaniola and Jamaica, and the Cayman Islands, Cuba, and Venezuela have an endemic species each. Limia are popular in aquaria among more advanced hobbyists.

Origin and evolution

Two schools of thought on the origin of the genus exist. The first suggests that Limia arose from colonization by a seawater-tolerant species that crossed over shallow waters from the North or South American mainland. The strongest evidence for this model is that of the approximately 60 species of freshwater fish in the Antilles, all of them are secondary division freshwater fish. This indicates the ancestors of all fish present on the islands at least had the ability to cross over shallow seas.

The second school of thought suggests freshwater fish in the Antilles are the descendants of mainland species that became isolated when some of the Greater Antilles split from the mainland. The virtual lack of freshwater fish fossils from the Antilles means this debate likely needs to be resolved through molecular evidence.

Some authorities regard the genus ''Limia'' as a synonym of ''Poecilia'', albeit as a valid subgenus.

Mating system

Fish in the genus ''Limia'' are lecithotrophic, meaning that there is pre-fertilization maternal provisioning in the form of yolked eggs. The female gives birth to live young, which have a higher chance of survival than eggs and earlier stage fry. Fertilization is achieved internally with the male's gonopodium, a modified anal fin used for sperm transfer. Because of the asymmetrical energy costs associated with internal fertilization, females in many Poeciliid species act as the choosy sex, with males exhibiting ornate coloration and morphology as well as elaborate courtship displays. However, ''Limia'' mostly lack display or extreme sexual dimorphism/dichromism. Of the known species, only the humpback limia (''L. nigrofasciata''), Perugia's limia (''L. Perugiae'') and the blackbelly or Jamaican limia (''L. melanogaster'') have been found to exhibit male courtship displays.
The majority of limia species rely on forced copulation, in which the male thrusts his gonopodium into the female's genital pore without a prior display. The consequence of this system of mating can be the undermining of female choice, halting the progression of sexual selection on male traits and in some cases inhibiting speciation.

Hybrids

Fertile hybrids have been obtained between ''L. melanogaster'' and both ''L. nigrofasciata'' and ''L. vittata''.

John Dawes in the UK, in his book ''Livebearing Fishes'', reported a ''L. melanogaster'' x ''L. nigrofasciata'' hybrid male has been mated to female green sailfin molly. Two hybrid fry were obtained, one was raised to maturity, ending up as a molly-like fish swimming with its head up at an angle of 45 degrees and was unable to maintain an even keel. This hybrid fails to inseminate molly females provided and no further hybrid offspring resulted.

Species

There are currently 23 recognized species in this genus:
* ''Limia caymanensis'' Rivas & W. L. Fink, 1970 (Grand Cayman limia)
* '' Limia dominicensis'' (Valenciennes, 1846) (Tiburon Peninsula limia)
* '' Limia fuscomaculata'' Rivas, 1980 (Blotched limia)
* '' Limia garnieri'' Rivas, 1980 (Garnier's limia)
* '' Limia grossidens'' Rivas, 1980 (Largetooth limia)
* '' Limia heterandria'' Regan, 1913
* '' Limia immaculata'' Rivas, 1980 (Plain limia)
* '' Limia islai'', Rodriguez-Silva & Weaver, 2020 (Tiger limia)
*'' Limia mandibularis''
* '' Limia melanogaster'' ( Günther, 1866) (Blackbelly limia)
* '' Limia melanonotata'' Nichols & G. S. Myers, 1923 (Blackbanded limia)
* '' Limia miragoanensis'' Rivas, 1980 (Miragoane limia)
* '' Limia nigrofasciata'' Regan, 1913 (Black-barred limia)
* '' Limia ornata'' Regan, 1913 (Ornate limia)
* '' Limia pauciradiata'' Rivas, 1980 (Few-rayed limia)
* '' Limia perugiae'' ( Evermann & H. W. Clark, 1906) (Perugia's limia)
* '' Limia rivasi'' L. R. Franz & G. H. Burgess, 1983 (Rivas's limia)
* ''Limia sulphurophila'' Rivas, 1980 (Sulfur limia)
* '' Limia tridens'' ( Hilgendorf, 1889)
* '' Limia versicolor'' ( Günther, 1866) (Varicolored limia)
* '' Limia vittata'' ( Guichenot, 1853) (Cuban limia)
* '' Limia yaguajali'' Rivas, 1980 (Yaguajal limia)
* '' Limia zonata'' (Nichols, 1915) (Striped limia)

See also

* Lake Miragoâne – lake in Haiti with at least 9 endemic ''Limia'' species

References

{{Taxonbar, from=Q134424

Poeciliidae
Freshwater fish genera
Taxa named by Felipe Poey
Ray-finned fish genera