Molecular phylogeny and morphology reveal three new species and two new records of Trichoderma (Hypocreaceae, Hypocreales) from China.

Species of Trichoderma are globally distributed across diverse ecosystems. In this study, four Trichoderma strains were isolated from Ophiocordyceps jinguangensis, two from O. sinensis, and two from Dracaena sp. To determine their taxonomic placement, maximum likelihood and Bayesian inference analyses of ITS, tef1-α, and rpb2 sequences, along with morphological examinations, were conducted. Integrating phylogenetic and morphological evidence, these strains were identified as three new species, Trichoderma diqingense, T. dracaenae, and T. yuxiense, which are distributed in three distinct clades of Trichoderma (i.e., Harzianum, Viride, and Polysporum, respectively), and two known species, T. fertile and T. paraviridescens, which are newly recorded from the substrate O. sinensis. Descriptions and illustrations of all species are provided. These findings expand the understanding of Trichoderma species and substrate diversity, providing a taxonomic basis for future studies.