Molecular phylogeny of Hyphoderma and the reinstatement of Peniophorella

Hyphoderma is a large genus of corticioid homobasidiomycetes. In earlier homobasidiomycete-wide molecular phylogenetic studies the genus has appeared as polyphyletic. This paper describes the results from phylogenetic analyses of 22 species of Hyphoderma using nuclear 5.8 S and 28 S rDNA. Species with echinocysts and stephanocysts form a distinct clade well separated from Hyphoderma s. str. For this group the old genus name Peniophorella is available with P. pubera as the type species. Nineteen new combinations in Peniophorella are made and a key to the species is given. The clade representing Hyphoderma in its restricted sense receives only indicative support and a further subdivision of the genus may become necessary. H. capitatum, H. orphanellum, and H. sibiricum belong neither to Peniophorella nor to Hyphoderma s. str. Hypochnicium is a sister group to Hyphoderma. The phylogenetic analyses support the segregation of Hypochnicium analogum and H. vellereum as Gloeohypochnicium analogum and Granulobasidium vellereum, respectively, and the inclusion of H. detriticum in Hyphodontia. Hyphodermopsis and Bulbillomyces are best regarded as synonyms of Hypochnicium.