Comparative mitogenomics and phylogenetic analyses of Meconematini (Orthoptera: Tettigoniidae: Meconematinae) provide insights into its systematic classification

Abstract The tribe Meconematini (Meconematinae) is a species-rich lineage whose genus- and species-level classifications remain taxonomically controversial. In this study, we obtained 17 new mitochondrial genomes using high-throughput sequencing and conducted the first comparative genomic and phylogenomic analyses within this tribe. The mitogenomes of Meconematini exhibit conserved structural features typical of Meconematinae, including conserved gene order, pronounced AT bias, and negative GC-skew. Notably, a rare mitochondrial initiation codon (GTG) was identified in the ATP6 gene in Meconematini. Evolutionary analyses indicated that strong purifying selection has dominated the evolution of Meconematini mitogenomes. Phylogenetic reconstructions strongly supported the monophyly of the genera Microconema Liu and Decma Gorochov, as well as the subgenus Eoxizicus Gorochov. In contrast, the genera Phlugiolopsis Zeuner, Xizicus Gorochov, and Xiphidiopsis Redtenbacher were not recovered as monophyletic. Additionally, the phylogenetic results support the recognition of Eoxizicus and Euxiphidiopsis Gorochov as distinct genera. Importantly, mitogenomic divergence patterns were correlated with genitalia structural traits: genera within the proximal clade possess membranous male genitalia (hagloid type), whereas those in more basal clades exhibit partially or fully sclerotized genitalia (tettigonioid or grylloid type). These findings collectively enable the proposal of taxonomic revisions for the non-monophyletic genera and establish a mitogenomic baseline for reconciling morphological convergence with evolutionary relationships in Meconematini.