STUDIES ON MONOPHYLY OF DANIONINE FISHES(TELEOSTEI:CYPRINIDAE),BASED ON SEQUENCE VARIATIONS OF THE S7 RIBOSOMAL PROTEIN GENE

The S7 ribosomal protein gene was used as a DNA marker for the phylogenetic analyses of Cyprinidae in present paper. Sequences of the 1st intron of the S7 ribosomal protein gene were determined by Polymerase Chain Reaction (PCR) for 13 species of cyprinid including 6 danionine species. An alignment of 743 nucleotide sites was used in the phylogenetic studies. Out of these sites, variable sites were 592 and parsimony informative sites 366. Sequence divergence among the cyprinids analyzed ranges from 2.6% between close species to 48.0% between distant species. The cladograms were produced using Neighbor-Joining method and Most-Parsimony method included in software MEGA. The present results indicate that the currently recognized Danionine fishes cannot be related as a monophyletic group. The location of Danio, Rasbora and Barilius closely nearing the root of the cladograms shows that they seem to be derived earlier from common cyprinid ancestor. Compared with these basal Danioninae genera, speciation of the genera Aphyocypris, Zacco and Opsariichthys occurred more recently and they may be closely related to the East Asian fish group.