Abstract
Marquandomyces is a recently established genus in the Clavicipitaceae and previously comprised only two known species. This study expands the understanding of its generic concept and species diversity through comprehensive fungal diversity surveys conducted from soil samples in China and Uzbekistan. As a result, five new species were identified based on morphological characterization and molecular phylogenetic analyses, and their detailed descriptions and illustrations are provided. This study emphasizes the unique ecological roles and specific habitats of these fungi and contributes to a relatively deep understanding of the genus Marquandomyces as well as its ecological significance.