Morpho-molecular approach reveals three novel endophytic fungi in Polyschema (Pleosporales, Latoruaceae) associated with roots of baobab trees in Yunnan, China

Endophytic fungi associated with roots of the baobab tree (<i>Adansonia digitata</i> L.) remain poorly documented in terms of species diversity worldwide. During an ongoing fungal survey in the dry-hot valleys of Honghe (Yunnan Province, China), five endophytic fungal strains were isolated from healthy roots of <i>A. digitata</i>. Based on multi-locus phylogenetic analyses of four loci (ITS, LSU, SSU, and <i>rpb</i>2), combined with morphological observations, all five strains were identified as belonging to the genus <i>Polyschema</i>. Hence, three novel species are introduced in the present study, namely <i>P. adansoniae-digitatae</i>, <i>P. hongheense</i>, and <i>P. radicicola</i>. This study constitutes the first record of <i>Polyschema</i> from mainland China. Detailed morphological descriptions, illustrations, and phylogenetic placements of the three new species are provided. Additionally, the species diversity, morphology, and phylogeny of <i>Polyschema</i> are updated and discussed. These findings enrich knowledge of endophytic fungal diversity associated with baobab in China and provide insights into the taxonomy and diversity of <i>Polyschema</i>. Furthermore, an updated discussion on the ecology and genera within the family Latoruaceae is presented.