Insights into the evolutionary history of Diestramimini cave crickets (Orthoptera, Rhaphidophoridae)

Diestramimini is one of the two tribes of Aemodogryllinae and is mainly distributed in southern China and Southeast Asia. The intergeneric phylogenetic relationship and historical biogeography of this tribe remain unclear. Here, we present the first phylogenetic and biogeographical analyses of Diestramimini based on three mitochondrial (COI, 12S rRNA and 16S rRNA) and two nuclear (18S rRNA and 28S rRNA) gene fragments. The molecular phylogenetic inference strongly supports the monophyly of Diestramimini and recovers the sister-group relationship between Diestramima + Tamdaotettix and Arboramima + Gigantettix. A new genus, Bidiestramima Zhu & Shi gen. n., is established and recovered as sister to all the remaining genera of Diestramimini. Moreover, a new species Bidiestramima hekouensis Zhu & Shi gen. et sp. n. is described. Mimadiestra is recovered as paraphyletic, and thus, we propose two new combinations based on the combination of morphological and molecular evidence: Bidiestramima dicha comb. n. and Tamdaotettix (Laotettix) gracilus comb. n. Divergence time estimation and reconstruction of ancestral areas indicate that Diestramimini in China may have originated from Southern Yunnan and Guangxi during the mid-Oligocene and had two separate evolutionary routes. The diversification of Diestramimini has been driven by several dispersal and vicariance events since the Miocene, linked to the uplift of the Himalaya-Tibetan Plateau, the formation of the monsoon and climate fluctuations.

Automated summary

This study provides the first phylogenetic and biogeographical analyses of Diestramimini, showing its sister-group relationship with Diestramima + Tamdaotettix and Arboramima + Gigantettix. A new genus, Bidiestramima, is established and a new species, Bidiestramima hekouensis, is described. The diversification of Diestramimini is attributed to dispersal and vicariance events influenced by the uplift of the Himalaya-Tibetan Plateau, the formation of the monsoon, and climate fluctuations.