Characterization of the complete mitochondrial genome of Biston marginata (Lepidoptera: Geometridae) and phylogenetic analysis among lepidopteran insects.

The complete mitochondrial genome (mitogenome) of Biston marginata (Lepidoptera: Geometridae) was determined and annotated. The circular genome is 15,470bp long and it contains the entire set of 37 genes usually present in lepidopteran mitogenomes. The nucleotide composition of the genome is highly A+T biased, accounting for 81.20%, with a slightly positive AT skewness (0.028), indicating the occurrence of more As than Ts, as found in other Geometridae species. Except for cox1 gene starts with non-canonical initial codon CGA, all protein-coding genes start with ATN codon. Three of the 13 PCGs (protein coding gene) had an incomplete termination codon, T or TA, while the others terminated with TAA. All tRNA genes are predicted to fold into typical clover-leaf secondary structure, except for the trnS1 (AGN), in which the dihydrouridine (DHU) arm could not form a stable stem-loop structure. The A+T-rich region of 343bp is comprised of non-repetitive sequences, but have several distinctive features, including the motif "ATAGA" followed by a 19bp poly-T stretch, a microsatellite-like (TA)7 element next to the ATTTA motif. The phylogenetic analyses support the view that the B. marginata is closely related to the Biston pantrinaria, and confirm that Biston marginata belongs to the family Geometridae.