Conclusions

In this study，the complete mt genome of the host cadaver(Thitarodes sp.)of O.sinensis，a circular molecule of 16，280bp in length，was determined using the combination of massively parallel DNA sequencing and PCR sequencing.The gene organization，base composition，and secondary structure of tRNA are similar to those of the other lepidopteran mt genomes.The gene arrangement is identical to the ancestral arrangement but different from those of other lepidopteran mt genomes due to the rearrangement of trnI，trnQ and trnM.The 1473bp AT-rich region located between the rrnS and trnI genes is the longest in a sequenced Thitarodes mt genome to date.Evolutionary analyses，including the phylogenetic tree，the genetic distances and the intergenic spacers in the mt genome，showed that the host cadaver of O.sinensis belongs to Thitarodes，while Endoclitasignifer and Napialus hunanensis form a relatively distinct lineage from Thitarodes.This is the first phylogenetic analysis to explore the placement of the host insect of O.sinensis based on molecular information.The sequence and full annotation of this moth mt genome will provide more molecular resources about Exoporia in the Lepidoptera，and the clarification of its phylogeny will benefit the management of this insect resource，as well as the conservation and sustainable use of this endangered medicinal species in China.(https://www.daowen.com)