Taxonomy and phylogeny of the genus Megasporoporia and its related genera

Taxonomic and phylogenetic studies on Megasporoporia s.l. were carried out. Phylogenetic analysis based on ITS and nLSU sequences showed that Megasporoporia s.l. belonging to the core polyporoid clade, however, it is not monophyletic, and four clades were recognized. The Megasporoporia s.s. clade includes M. setulosa and two new species, M. bannaensis and M. minor spp. nov. Two monophyletic clades were segregated from Megasporoporia s.l., and two new genera were established. Megasporia gen. nov. is composed of M. cystidiolophora, M. ellipsoidea, M. hexagonoides, M. major, M. violacea, and two new species, M. guangdongensis and M. hengduanensis spp. nov. Megasporoporiella gen. nov. including M. cavernulosa, M. rhododendri, M. subcavernulosa, and two new species, M. lacerata and M. pseudocavernulosa spp. nov. Megasporoporia quercina grouped with Grammothele fuligo in the Grammothele clade, so it is transferred to Grammothele and a new combination, G. quercina, is proposed. The main morphological characters of Megasporoporia and the two new genera are discussed, and identification keys to the three genera are provided.