Polypores and genus concepts in Phanerochaetaceae (Polyporales, Basidiomycota)

Abstract

We explored whether DNA-phylogeny-based and morphology-based genus concepts can be reconciled in the basidiomycete family Phanerochaetaceae. Our results show that macromorphology of fruiting bodies and hymenophore construction do not reflect monophyletic groups. However, by integrating micromorphology and re-defining genera, harmonization of DNA phylogeny and morphological genus concepts is possible in most cases. In the case of one genus (Phlebiopsis), our genetic markers could not resolve genus limits satisfactorily and a clear morphological definition could not be identified. We combine extended species sampling, microscopic studies of fruiting bodies and phylogenetic analyses of ITS, nLSU and rpb1 to revise genus concepts. Three new polypore genera are ascribed to the Phanerochaetaceae: Oxychaete gen. nov. (type Oxyporus cervinogilvus), Phanerina gen. nov. (type Ceriporia mellea), and Riopa (including Ceriporia metamorphosa and Riopa pudens sp. nov.). Phlebiopsis is extended to include Dentocorticium pilatii, further species of Hjortstamia and the monotypic polypore genus Castanoporus. The polypore Ceriporia inflata is combined into Phanerochaete. The identity of the type species of the genus Riopa, R. davidii, has been misinterpreted in the current literature. The species has been included in Ceriporia as a species of its own or placed in synonymy with Ceriporia camaresiana. The effort to properly define R. davidii forced us to study Ceriporia more widely. In the process we identified five closely related Ceriporia species that belong to the true Ceriporia clade (Irpicaceae). We describe those species here, and introduce the Ceriporia pierii group. We also select a lectotype and an epitype for Riopa metamorphosa and neotypes for Sporotrichum aurantiacum and S. aurantium, the type species of the anamorphic genus Sporotrichum, and recommend that teleomorphic Riopa is conserved against it.