An unusual neotropical cichlid has received considerable attention from evolutionary
biologists because of discrete, pronounced morphological and trophic
variation. The specific status of this fish had been unresolved because the magnitude
of morphological variation suggested the existence of at least three closely
related taxa (LaBounty 1974), while biochemical analysis strongly supported the
existence of a single polymorphic species (Sage and Selander 1975). Recent field
studies (Kornfield et al. 1982) have confirmed the biochemical analyses and established
conspecificity among morphological variants. Described here is Cichlasoma
minckleyi, a new species of polymorphic cichlid endemic to the Cuatro
Cienegasbasin, Coahuila, Mexico.