Tricladiaceae fam. nov. (Helotiales, Leotiomycetes)

To resolve the polyphyletic nature of Solenopeziaceae as it was originally circumscribed, we establish a new family Tricladiaceae for those genera originally placed in Solenopeziaceae that have aquatic hyphomycetelike asexual morphs and/or a sexual morph with glabrous apothecia. These include Cudoniella, Geniculospora, Graddonia, Halenospora, Mycofalcella, Spirosphaera, and Tricladium. Solenopeziaceae is confined to the genera Lasiobelonium, Solenopezia, Trichopeziza, and Trichopezizella, all of which have a sexual morph having apothecia with smooth-walled hairs. This taxonomy is supported by a multi-gene analysis using up to 15 genes, with a few of the taxa placed on the basis of a separate ITS phylogeny. Tricladiaceae forms a monophyletic clade with a basal sister relationship to Pleuroascaceae plus Helotiaceae; Solenopeziaceae forms a monophyletic clade with a basal sister relationship to Lachnaceae.