Complete mitochondrial genome of the tea looper caterpillar, Ectropis obliqua (Lepidoptera: Geometridae) with a phylogenetic analysis of Geometridae.

The complete mitochondrial genome (mitogenome) of the Ectropis obliqua (Lepidoptera: Geometridae) was sequenced and compared with other species of Geometridae. The mitochondrial genome of E. obliqua is 15,475bp long and contains 37 genes including 13 protein coding genes (PCGs), 22 transfer RNA genes, 2 ribosomal RNA genes and an A+T-rich region. Gene cluster trnI-trnQ-trnM rearranged to trnM-trnI-trnQ comparing with the ancestral mitogenome of insects. All tRNA genes have typical cloverleaf secondary structure except for trnS (AGN). All the sequenced mitogenomes from Geometridae have negative AT-skews and positive GC-skews except for Biston suppressaria. The synonymous and nonsynonymous substitutions ratios (Ka/Ks) indicated variable selective pressures among 13 PCGs. The phylogenetic relationship among 11 species of Geometridae was recovered based on 13 protein coding genes and 2 rRNA genes using Bayesian inference. E. obliqua is grouped with other Ennominae species and recovered to be sister-relationship with Abraxas suspecta.