Revised: Synonymisation of Under and Establishment of a New Order, Thyridiales

The genus , previously known as a saprobic or hemibiotrophic ascomycete on various plants, was revised taxonomically and phylogenetically. Sequences of the following six regions, that is, the nuclear ribosomal internal transcribed spacer (ITS) region, the large subunit (LSU) of rDNA, the second largest RNA polymerase II subunit () gene, translation elongation factor 1-alpha () gene, the actin () gene, and the beta-tubulin () gene, were generated for molecular phylogenetic analyses of species of this genus. , a genus encompassing medically important species, is synonymised with based on molecular evidence and morphological similarities in their asexual characters. The generic concept for is expanded to include species possessing both coelomycetous and hyphomycetous complex asexual morphs. In addition to type species of , , nine species were accepted in upon morphological comparison and molecular phylogenetic analyses in this study. All seven species of were treated as members of the genus and new combinations were proposed. A bambusicolous fungus, , was transferred to , and an epitype is designated for this species. A new species, , was described from . The family Phialemoniopsidaceae, proposed as a familial placement for , was regarded as a synonym of Thyridiaceae. A new order, Thyridiales, was established to accommodate Thyridiaceae; it forms a well-supported, monophyletic clade in Sordariomycetes.