Two novel Helicosporium species (Tubeufiaceae, Tubeufiales) from southern China based on morphological and molecular evidence

During a survey of saprobic fungi, fresh specimens were collected from decaying wood in terrestrial habitats in Guizhou and Hainan provinces, southern China. Two novel species, <i>Helicosporium qixianlingense</i> and <i>H. tongrenense</i>, are introduced based on phylogenetic analyses of a combined dataset (ITS, LSU, <i>tef</i>1-α, and <i>rpb</i>2) and morphological evidence. Comprehensive descriptions, illustrations, notes, and phylogenetic analyses supporting the taxonomic placement of these new taxa are provided. These findings are significant for exploring the species diversity of <i>Helicosporium</i> in southern China.