New insights into Clonostachys: description of a novel species and expanded host range

Clonostachys (Bionectriaceae, Hypocreales) comprises fungi with diverse ecological roles and widespread distribution. We describe a novel species, Clonostachys mangrovei. Both sexual and asexual morphs are characterized, with the sexual morph being particularly significant, as most Clonostachys species are known only from their asexual states, which are often difficult to distinguish. Phylogenetic analysis based on a combined dataset of ITS, LSU, RPB-2, TEF, and TUB sequences places C. mangrovei in a well-supported clade, closely related to C. viticola. Although these two species share similar asexual characteristics, a common feature within the genus, this overlap underscores the morphological importance of the sexual morph and of molecular data for reliable species delimitation. Ecologically, C. mangrovei represents the first confirmed member of the genus adapted to mangrove environments, highlighting the ability of Clonostachys to extend beyond its predominantly terrestrial range and contributing to the growing recognition of fungal diversity in marine-influenced ecosystems. In addition, we report a new host and geographic record for C. farinosa, its first occurrence on Swietenia mahagoni in Thailand.