MIYA, M.; NISHIDA, M.; Nat. Hist. Mus. Inst., Chiba; Ocean Res. Inst., Univ. of Tokyo: Major patterns of actinopterygian phylogenies: A new perspective based on >200 complete mitochondrial DNA sequences

Actinopterygii, the ray-finned fish, is the most diversified group of all vertebrates, currently comprising over 25,000 species placed in 42 orders, 431 families, and 4075 genera. Because of the enormous species’ diversity involved, ancient origin that goes back some 400 million years ago, and the wide ranging variations not only in morphology but also in behavior, ecology, and physiology, there remains much controversy over the higher-level relationships of actinopterygians. Our research group has determined complete mitochondrial DNA sequences from unprecedentedly large number of species (ca. 400) that covers a whole spectrum of actinopterygian diversity. We will present results from phylogenetic analyses of this large data set which is divided into the following three hierarchical levels: 1) basal actinopterygians; 2) higher actinopterygians; and 3) percomorphs. We have discovered many examples of previously-unrecognized, major comprehensive groups of actinopterygians with high statistical support through preliminary phylogenetic analysis.