Addition to Microascales (Sordariomycetes, Ascomycota): Synnematotriadelphiaceae fam. nov., <i>Triadelphia mukdahanensis</i> sp. nov.<italic/> (Triadelphiaceae) and the validation of Graphiaceae

Abstract

A new species, <italic>Triadelphia</italic> <italic>mukdahanensis</italic> from northeastern Thailand, is introduced based on morphology and multi-gene phylogeny of combined ITS, LSU, SSU, and RPB2 sequence datasets. Phylogenetic analysis indicates that <italic>T.</italic> <italic>mukdahanensis</italic> is closely related to <italic>T. heterospora</italic> with high bootstrap support. However, <italic>T.</italic> <italic>mukdahanensis</italic> is distinct from <italic>T. heterospora</italic> and other exist species in conidial characteristics. In addition, the present study clarifies the current taxonomic placement of the genus <italic>Synnematotriadelphia</italic> based on phylogenetic analyses. The result shows that <italic>Synnematotriadelphia</italic> forms a distinct lineage in the clade comprising Triadelphiaceae and Graphiaceae. Therefore, a new family, Synnematotriadelphiaceae, is introduced to accommodate this distinct lineage and Graphiaceae is also validated herein.