The Mitochondrial Genome of (Cypriniformes: Cyprinidae): Characterization and Phylogeny.

Mitochondrial genomes (mitogenomes) have been widely used in phylogenetic analysis and evolutionary biology. The Labeoninae is the largest subfamily of Cypriniformes and has great economic importance and ecological value. In this study, we sequenced, annotated, and characterized the complete mitogenome of and then constructed the phylogenetic tree with previously published Labeoninae mitogenomes. The mitogenome of . was 16,593 bp in length, with an A + T content of 57.1%. The mitogenome contained a standard set of 37 genes and a control region with the same order and orientation of genes as most fish mitogenomes. Each protein-coding gene (PCG) was initiated by an initial ATG codon, excluding , that began with a GTG codon. Furthermore, most of the PCGs were terminated by a conventional stop codon (TAA/TAG), while an incomplete termination codon (TA/T) was detected in 7 of the 13 PCGs. Most tRNA genes in . were predicted to fold into the typical cloverleaf secondary structures. The / (ω) values for all PCGs were below one. The phylogenetic relationships of 96 Labeoninae mitogenomes indicated that Labeoninae was not a monophyletic group and . was closely related to the genera and . Overall, our study provided the first complete annotated mitogenome of . , which filled a knowledge gap in Labeoninae and extended the understanding of the taxonomy and mitogenomic phylogeny of the subfamily Labeoninae.