Phylogeny of Limia (Teleostei : Poeciliidae) based on NADH dehydrogenase subunit 2 sequences

Complete sequences for the mitochondrial gene NADH Dehydrogenase 2 (ND2) an d partial sequences for the tRNA-Met and tRNA-Trp genes were obtained for 1 1 populations of the poeciliid fish genus (or subgenus) Limia, including sp ecies from Hispaniola, Cuba, Jamaica, and Grand Cayman Islands. Additional sequences for Limia (2 species), Pamphorichthys (3), Poecilia (16), and Xip hophorus (1), all from the tribe Poeciliini, were extracted from GenBank, a s was a sequence for Heterandria formosa, from the tribe Heterandriini, Phy logenetic analyses included parsimony, distance methods, and maximum-likeli hood. Several Limia species groups that had been proposed based on morpholo gical data were evaluated. The versicolor species group was strongly suppor ted, as was the close relationship between the Cuban Limia vit tata and the Grand Cayman Limia caymanensis. However, the proposed vittata species grou p was not upheld by the ND2 data. The phylogenetic position of Limia melano gaster, from Jamaica, was either sister to the versicolor species group or basal to all other included Limia species. Limia was found to be monophylet ic; however, Limia species from the island of Hispaniola were not monophyle tic. There was little support for any proposed sister group to Limia. The p hylogeny was used to reconsider a previous comparative study of poeciliid c ourtship behavior and sexual dimorphism. The data indicated that there may have been two independent appearances of courtship display behavior in Limi a; considering the tribe Poeciliini as a whole, there is evidence for as ma ny as five appearances of display (including two within Limia), or a comple x pattern of gains and losses of such behavior. The application of phylogen etic information to the comparative study did not refute the previously hyp othesized correlation between the presence of a courtship display and the p resence of sexual dimorphism in poeciliid fish. (C) 2001 Academic Press.