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.

Interspecific Hybridization and Complete Mitochondrial Genome Analysis of Two Ghost Moth Species

“…and T. damxungensis [21]. Based on the phylogenetic tree constructed by 13 PCGs from the previously described genomes, GG♂× GG♀ was identified as T. shambalenensis, and SD♂× SD♀ was considered to be an undescribed Thitarodes species (Figure 5), given the reasonable threshold for inter-species variation (2.5% genetic distance) [43,64]. Interestingly, SD♂× GG♀ was close to GG♂× GG♀, according to the genetical similarities, which confirms the maternal inheritance of mitochondrial DNA.…”

“…T. shambalaensis (GG♂× GG♀) identified by morphology (male genitalia) and genetic cox1 phylogeny [43] and an undescribed Thitarodes species (SD♂× SD♀) live in different locations in the Tibetan Plateau. In the present study, interspecific hybridization between these two distinct ghost moth species was demonstrated in the laboratory.…”

“…Coptotermes formosanus and Coptotermes gestroi [59] and between Reticulitermes flaviceps and Reticulitermes chinensis [43]. The red imported fire ant Solenopsis invicta, black imported fire ant Solenopsis richteri and their hybrid (S. invicta × S. richteri) are present in the field in Tennessee, USA [60].…”

“…The SD♂× SD♀ population from Sichuan Province, China, was considered to be an undescribed Thitarodes species, by the phylogenetic analysis, although the valve pattern of the male genitalia of SD♂× SD♀ resembled that of Thitarodes kangdingensis (Figure 1) (Prof. Zhiwen Zou, personal communication). The GG♂× GG♀ population also from Sichuan Province, China, was confirmed to be Thitarodes shambalaensis [43], based on the valve pattern of the male genitalia (Figure 1) and the sequences of the cox1 fragment. The complete cox1 sequences of the two species were 1531 bp and were submitted to GenBank (accession numbers OK104111 and OK047724, respectively).…”

“…The pupae of two Thitarodes insect populations were, respectively, from the mountains in Gongga (referred to as GG♂× GG♀) (2476 m, 29 The valve pattern of the male genitalia is an important characteristic for the morphological identification of Hepialidae insects [42,43]. The female and male Thitarodes pupae were differentiated by their genitalia.…”