Thunnus alalunga is an excellent food fish and is of great importance in recreational fisheries. In the study, the complete mitochondrial genome (mitogenome) of T. alalunga is sequenced and annotated, which is a circular DNA molecule with 16,527 bp in length. The overall nucleotide base composition of T. alalunga mitogenome is as follows: A, 28.37%; G, 16.69%; T, 25.46%; and C, 29.49%, with the A+T content of 53.83%, showing an obvious anti-G bias. The entire mitogenome encodes 37 genes in all, comprising 13 protein-coding genes (ATP6 and ATP8, COI-III, Cytb, ND1-6 and 4L), 22 transfer RNA genes (tRNAs), and two ribosomal RNA genes (12S and 16S rRNAs). The complete mitochondrial genome sequence of T. alalunga can provide useful information for the studies on molecular systematics, stock evaluation, and conservation genetics of teleost fishes.
Keywords: Conservation genetics; Thunnus alalunga; mitochondrial genome; molecular systematics; stock evaluation.