The complete mitochondrial genome of the doubled-lined mackerel Grammatorcynus bilineatus Rüppell, 1836 (Perciformes: Scombridae) from Beqa lagoon in Fiji.

The complete mitochondrial genome of the doubled-lined mackerel, Grammatorcynus bilineatus, was determined by the combination of high-throughput sequencing (HTS) and Sanger sequencing. The constructed mitochondrial genome of G. bilineatus was 16,537 bp in length, which harbors a canonical 37 genes (13 proteins, two ribosomal RNAs, and 22 tRNAs) and two non-coding regions (origin of light-strand replication (OL) and the D-loop control region). Among 38 genes, nine were encoded on its light strand (L), while the other 28 were on its heavy strand (H). Besides COX1 (GTG) and ATP6 (CTG), the other eleven protein-coding genes (PCGs) begin with a typical start codon (ATG). The phylogenetic tree showed that G. bilineatus was not clustered with the other species in the Scombridae, forming a clade for Grammatorcynus. The genetic information of G.bilineatus will provide useful information for the scientific management and conservation of the species in the genus.