Mitochondrial genome of the shorthead catfish (Pelteobagrus eupogon): structure, phylogeny, and intraspecific variation.

The complete 16,532-nucleotide sequence of the mitochondrial genome of the shorthead catfish (Pelteobagrus eupogon) was determined using the long and accurate polymerase chain reaction method, and compared with the mitochondrial genome sequences of 49 other catfish species belonging to the order Siluriformes. The locations of protein-coding genes and ribosomal ribonucleic acids (RNAs) were identified by comparison with known sequences of other catfishes, including P. fulvidraco and P. nitidus. The P. eupogon mitochondrial genome was composed of 13 protein-coding genes, two ribosomal RNAs, 22 transfer RNA genes, and a non-coding control region. The gene order was identical to that of other Siluriformes. Phylogenetic analyses based on mitochondrial 12S ribosomal RNA, 16S ribosomal RNA, and 13 protein-coding gene sequence data sets were carried out to further clarify the relative phylogenetic position of P. eupogon, and identify phylogenetic relationships among 24 families of Siluriformes. Phylogenetic analyses Randomized Axelerated Maximum Likelihood (RAxML) 8.0.X were congruent with a basal split of the order into Clupeiformes, Characiformes, Cypriniformes, and Siluriformes, and supported a closer relationship of P. eupogon with Amblycipitidae than Siluridae. We therefore concluded that this species appears to be closely related to the Amblycipitidae. In the phylogenetic tree, the Amblycipitidae appeared as the most basal extant lineage within the Siluriformes, while the Bagridae appeared as the sister group of Cranoglanididae and Pangasiidae. The mitochondrial genome sequence of P. eupogon has been deposited in GenBank (accession No. KJ001784).