Thitarodes shambalaensis sp. nov. (Lepidoptera, Hepialidae): a new host of the caterpillar fungus Ophiocordyceps sinensis supported by genome-wide SNP data

Abstract

A new species of ghost moth, Thitarodes shambalaensissp. nov., is described from Yanzigou glacier, Mt. Gongga, Sichuan, China. The species is a host of the economically important caterpillar fungus Ophiocordyceps sinensis. Establishment of this new species is supported by morphology and genetic differentiation measured in a CO1 phylogeny and in genome-wide SNP coverage. A summary tree from 538 sequences of different genetic markers from Thitarodes (including sequences extracted from caterpillar fungus sclerotium samples) support the genus Thitarodes as a monophyletic group, and indicate that Thitarodes is the host genus for O. sinensis. Sampling efforts so far have centered on half of the known phylogenetic diversity of Thitarodes, with some species-level clusters (separated by < 2.5% genetic distance) containing 17 described species. Fifteen clusters are known from either a single “orphan taxon” or a single sequence from a caterpillar fungus sclerotium sample. We provide suggestions for building a more robust phylogeny of the genus Thitarodes and highlight some of the conservation threats that species from this genus face due to unprecedented habitat exploitation.