Description of two new species of Ophiocordyceps: O. sinocampes and O. cystidiata (Ophiocordycipitaceae, Hypocreales) from typical karst landform forests in Guizhou, China

Karst habitats are hotspots of diversity and endemism. Their naturally fragmented distributions across broad geographic landscapes have led to a complex array of smaller evolutionary ecosystems. Comprehensive biodiversity assessments of karst habitats have revealed that these ecosystems contain a high level of endemism. During a survey of cordycipitoid fungi in the karst region of southwest Guizhou, China, we identified and proposed two new species, based on morphology and multi-locus (nrSSU, nrLSU, <i>tef</i>, <i>rpb1</i>, and <i>rpb2</i>) phylogenetic analyses. <i>O.cystidiata</i> <b>sp. nov.</b> is characterized by gray-white to yellow fertile part, verrucose phialides, and conidia enveloped in a cystic thickened mucus sheath, distinguishing it from other species. <i>O.sinocampes</i> <b>sp. nov.</b> is distinguished by long tapering phialides with inflated bases. Phylogenetic analyses using five loci reveal that <i>O.cystidiata</i> shares a close relationship with <i>O.fenggangensis</i>, <i>O.musicaudata</i>, <i>O.alboperitheciata</i>, and <i>Hirsutellakuankuoshuiensis</i>, while <i>O.sinocampes</i> is closely related to <i>O.multiperitheciata</i> and <i>H.strigosa</i>. Herein, we completed the descriptions, illustrations and molecular phylogeny of these two new species. The host diversity of <i>O.sinocampes</i> has also been documented within the orders Lepidoptera and Coccoidea. Our research further enriches the diversity of cordycipitoid species in the typical karst landform areas of Guizhou, China.