Abstract: 【Aim】To sequence the complete mitochondrial genome of Gotra octocinctus, anlayze and explore the genome structure and phylogenetic relationship of Ichneumonoidea. 【Methods】 The complete mitochondrial genome of G. octocinctus was firstly sequenced on the Illumina NovaSeq platform, and then the general features and base composition of the mitochondrial genome were analyzed. Combined with the 47 mitochondrial genome sequences of Ichneumonoidea published in GenBank, the phylogenetic trees of Ichneumonoidea were constructed with two species in Chalcidoidea as outgroups based on the 13 proteincoding gene (PCG) sequences using Bayesian inference (BI) and maximum likelihood (ML) methods. 【Results】The fulllength mitochondrial genome of G. octocinctus is 16 003 bp (GenBank accession no.： OP850580.1), and consists of 22 tRNA genes, 13 PCGs, two rRNA genes and one control region (CR). The base composition of mitochondrial genome was clearly AT-biased and exhibited the negative AT-skew and GC-skew. There were four gene rearrangements, 13 overlapping regions (in total 85 bp) and 17 interspaced regions (in total 1 072 bp) in the mitochondrial genome of G. octocinctus. The phylogenetic tree based on 13 PCG sequences showed that Eucerotinae is a natural monophyletic group, the Aphidiinae and the “cyclostome” of Braconidae are sister group. 【Conclusion】 In this study, we sequenced and analyzed the complete mitochondrial genome of G. octocinctus, and found that the trnI-trnQ-trnM gene rearrangement events are common in the mitochondrial genome of Ichneumonidae, providing data for the further systematic research of mitogenomes of Ichneumonoidea.

Key words: Ichneumonoidea; Gotra octocinctus, mitochondrial genome, gene rearrangement, phylogeny