Abstract
Kevinhydea brevistipitata gen. et sp. nov., and Helicoma hydei sp. nov., collected on decaying wood in terrestrial and freshwater habitats, respectively, are described and illustrated. Kevinhydea brevistipitata, the type species for a novel monotypic genus (Kevinhydea), is characterized by its macronematous, short conidiophores, and dictyosporous conidia. Helicoma hydei morphologically resembles H. guttulatum, but they are phylogenetically distinct species. Phylogenetic analyses of combined LSU, ITS, and TEF1 sequence data of 63 taxa were carried out to infer the phylogenetic affinity of new taxa within the family Tubeufiaceae. Additionally, phylogenetic analyses for the genus Helicoma, comprising 33 taxa, were performed separately to justify the new species H. hydei. Kevinhydea brevistipitata and Helicoma hydei are phylogenetically distinct from other species in Tubeufiaceae. A morphological comparison of dictyosporous hyphomycete genera in Tubeufiaceae is provided.