Next-Generation Sequencing of Four Mitochondrial Genomes of Dolichovespula (Hymenoptera: Vespidae) with a Phylogenetic Analysis and Divergence Time Estimation of Vespidae

SIMPLE SUMMARY: Mitochondria are vital organelles found in most eukaryotes that are involved in energy metabolism. The mitochondrial genome (mtgenome) is the genetic material of mitochondria, which is responsible for the coding and translation of proteins needed by organelles. By studying the mtgenomes of insects, we can better comprehend the phylogenetic relationships and molecular evolution of insects. The mtgenomes of four wasps are described in this paper, along with comparative genomic analyses. There are gene rearrangement events and 37 genes in each of the four mtgenomes. The subfamily Stenogastrinae is the sister group to the remaining Vespidae family, and according to our concluding analysis, the genus Vespa is more closely linked to the genus Vespula than to the genus Dolichovespula. We provide new evidence for the two-origin hypothesis of eusociality in the Vespidae. This work will aid us in future research on species evolution and phylogeny in the family Vespidae. ABSTRACT: The wasp genus Dolichovespula (Hymenoptera: Vespidae: Vespinae) is a eusocial wasp group. Due to the taxonomic and phylogenetic issues with the family Vespidae, more genetic data should be gathered to provide efficient approaches for precise molecular identification. For this work, we used next-generation sequencing (also known as high-throughput sequencing) to sequence the mitochondrial genomes (mtgenomes) of four Dolichovespula species, viz. D. flora, D. lama, D. saxonica, and D. xanthicincta 16,064 bp, 16,011 bp, 15,682 bp, and 15,941 bp in length, respectively. The mitochondrial genes of the four species are rearranged. The A + T content of each mtgenome is more than 80%, with a control region (A + T-rich region), 13 protein-coding genes (PCGs), 22 tRNA genes, and two rRNA genes. There are 7 to 11 more genes on the majority strands than on the minority strands. Using Bayesian inference and Maximum-Likelihood methodologies as well as data from other species available on GenBank, phylogenetic trees and relationship assessments in the genus Dolichovespula and the family Vespidae were generated. The two fossil-based calibration dates were used to estimate the origin of eusociality and the divergence time of clades in the family Vespidae. The divergence times indicate that the latest common ancestor of the family Vespidae appeared around 106 million years ago (Ma). The subfamily Stenogastrinae diverged from other Vespidae at about 99 Ma, the subfamily Eumeninae at around 95 Ma, and the subfamily Polistinae and Vespinae diverged at approximately 42 Ma. The genus Dolichovespula is thought to have originated around 25 Ma. The origin and distribution pattern of the genus Dolichovespula are briefly discussed.