Revisiting Xylaria diversity in Southern China: Descriptions of 40 new species

The genus Xylaria comprises a diverse group of fungi with a global distribution and significant ecological importance, known for being a source of bioactive secondary metabolites with antibacterial, antioxidative, anticarcinogenic, and additional properties. In this study, we present a comprehensive taxonomic revision of the species of Xylaria found in some parts of southern China, characterized by an extensive multilocus phylogeny analysis based on internal transcribed spacer (ITS), TUB2 (β‐tubulin), and DNA‐directed RNA polymerase II subunit 2 (rpb2) gene regions. Morphological examination and detailed comparative analyses of the collected specimens were conducted to determine the distinctiveness of each species. The multilocus phylogeny approach allowed us to infer evolutionary relationships and assess species boundaries accurately, leading to the identification of 40 novel Xylaria species hitherto unknown to science. The newly described species are: X. baoshanensis, X. bawanglingensis, X. botryoidalis, X. dadugangensis, X. doupengshanensis, X. fanglanii, X. glaucae, X. guizhouensis, X. japonica, X. jinghongensis, X. jinshanensis, X. kuankuoshuiensis, X. liboensis, X. negundinis, X. orbiculati, X. ovata, X. pseudoanisopleura, X. pseudocubensis, X. pseudobambusicola, X. pseudoglobosa, X. pseudohemisphaerica, X. pseudohypoxylon, X. puerensis, X. qianensis, X. qiongzhouensis, X. rhombostroma, X. serratifoliae, X. shishangensis, X. shuqunii, X. shuangjiangensis, X. sinensis, X. tongrenensis, X. umbellata, X. xishuiensis, X. yaorenshanensis, X. yinggelingensis, X. yumingii, X. yunnanensis, X. zangmui, and X. zonghuangii. The study's findings shed light on the distinctiveness of the newly described species, supported by both morphological distinctions and phylogenetic relationships with their close relatives. This taxonomic revision significantly contributes to our understanding the diversity of Xylaria in China and enriches the knowledge of fungal biodiversity worldwide.