Abstract
During our investigations of saprobic fungi, five fungal collections from terrestrial habitats in China and Thailand were examined using both morphological and multi-gene phylogenetic approaches (LSU, ITS, tef1-α, and rpb2), resulting in the identification of three novel species: Helicosporiumrubrum, Neohelicomycesmaolanensis, and N.subtropicus. Helicosporium and Neohelicomyces are morphologically similar in their asexual morphs but can be distinguished based on their molecular phylogenetic data. In this study, our new species, Helicosporiumrubrum, represents the fourth sexual species within the genus, characterized by yellow-brown ascomata and fusiform ascospores. Detailed descriptions, illustrations, phylogenetic analysis results, and corresponding notes are provided to clarify the distinctions between these new species and related taxa.