Mitochondrial phylogenomics of pygmy grasshoppers (Orthoptera, Tetrigidae, Metrodorinae): descriptions of a new genus, two new species, and new synonyms from China

The Chinese wingless brachypronotal pygmy grasshoppers of the subfamily Metrodorinae have often been classified within the genus <i>Macromotettixoides</i>. In this study, two undescribed species of wingless brachypronotal pygmy grasshoppers belonging to Metrodorinae were collected. To elucidate their taxonomic positions, the complete mitochondrial genomes of these two species were sequenced and analyzed. Phylogenetic analyses were conducted using 13 protein-coding genes (PCGs) from 28 tetrigid mitogenomes. Genetic distances and divergence times were estimated. Our results indicate that one species represents a new genus within Metrodorinae, while the other is a new species of <i>Macromotettixoides</i>. Consequently, a new genus and two new species of Metrodolrinae from China are described and illustrated: <i>Edentatettix</i> Deng, <b>gen. nov.</b> containing <i>Edentatettixleyeensis</i> Deng, <b>sp. nov.</b>, and <i>Macromotettixoidesyaana</i> Deng, <b>sp. nov.</b> Additionally, five new synonyms are proposed: <i>Hainantettixangustivertex</i> (Zha & Peng, 2021), <b>syn. nov.</b> and <i>Macromotettixoidesangustivertex</i> Zha & Peng, 2021, <b>syn. nov.</b> of <i>Hainantettixstrictivertex</i> Deng, 2020; <i>Hyboellabadagongshanensis Zheng</i>, 2013, <b>syn. nov.</b>, <i>Macromotettixoidesbadagongshanensis</i> (Zheng, 2013), <b>syn. nov.</b>, and <i>Macromotettixoideswuyishana</i> Zheng, 2013, <b>syn. nov.</b> of <i>Macromotettixoidesjiuwanshanensis</i> Zheng, Wei & Jiang, 2005. For the first time, edentate ovipositors constituting an important taxonomic character within Tetrigidae is reported and discussed.