Complete mitochondrial genome sequence of Tridentiger bifasciatus and Tridentiger barbatus (Perciformes, Gobiidae): a mitogenomic perspective on the phylogenetic relationships of Gobiidae.

The fishes of suborder Gobioidei is the largest group of those in present living Perciformes, which contains about 2,200 species belonging to 270 genera of 9 families in the world. The monophyly and phylogenetic relationships of gobies have been controversial and disputable for a long time. In the present study, the complete mitochondrial genome of the shimofuri goby Tridentiger bifasciatus (T. bifasciatus) and shokihaze goby Tridentiger barbatus (T. barbatus) were firstly determined. The two mitochondrial genomes were both consisted of 2 ribosomal RNA (rRNA) genes, 13 protein-coding genes, 22 transfer RNA (tRNA) genes, and one major control region (CR). They shared similar features with those of other gobies in terms of gene arrangement, base composition, and tRNA structures. The CR was absence of typical conserved blocks (CSB-E, and CSB-F) respectively for the T. bifasciatus and T. barbatus. Phylogenomic analyses, which based on 12 concatenated protein-coding genes and complete mitochondrial genome sequences, revealed that there were two groups within the Gobiidae. A large group consisted of the Amblyopinae, Gobionellinae, Oxudercinae and Sicydiinae, and Amblyopinae was nested in Oxudercinae and they were both paraphyletic to Sicydiinae. The other group was the Gobiinae. As a whole, our phylogenetic data was different from the traditionally classification of Gobiidae, but supported the new phylogenetic taxonomy view of Thacker (Copeia 2009:93-104, 2009).