Mitochondrial Genomes Yield Insights into the Basal Lineages of Ichneumonid Wasps (Hymenoptera: Ichneumonidae)

We obtained four mitochondrial genomes of Odontocolon sp., Xorides funiuensis, Euceros kiushuensis and Euceros serricornis, which represent the first two representatives from subfamily Eucerotinae and Xoridinae (Ichneumonidae), respectively. All of the 4 newly sequenced mitochondrial genomes contain 13 protein-coding genes (PCGs) and most 24 RNA genes. Furthermore, they all have novel tRNA rearrangement patterns comparing with published mitogenomes in Ichneumonidae. For the tRNA cluster trnI-trnQ-trnM, X. funiuensis is shuffled as trnM-trnI-trnQ with trnQ inversed, while Odontocolon sp. with a remote translocation of trnK, shuffling as trnI-trnM-trnQ. E. kiushuensis and E. serricornis shared the same cluster trnQ-trnY-trnW-trnC. Finally, we reconstructed the phylogenetic relationships among the sequenced subfamilies of Ichneumonidae based on nucleotides and amino acids sequences of 13 PCGs in mitochondrial genomes, and the results of both the maximum likelihood and Bayesian inference analyses highly support that Eucerotinae is the basal ichneumonid lineage rather than Xoridinae.