Abstract
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, tef, rpb1, and rpb2) phylogenetic analyses. O.cystidiata sp. nov. 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. O.sinocampes sp. nov. is distinguished by long tapering phialides with inflated bases. Phylogenetic analyses using five loci reveal that O.cystidiata shares a close relationship with O.fenggangensis, O.musicaudata, O.alboperitheciata, and Hirsutellakuankuoshuiensis, while O.sinocampes is closely related to O.multiperitheciata and H.strigosa. Herein, we completed the descriptions, illustrations and molecular phylogeny of these two new species. The host diversity of O.sinocampes 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.