Taxonomy and phylogeny of Pyrrhoderma: a redefinition, the segregation of Fulvoderma, gen. nov., and identifying four new species.
Previously, Pyrrhoderma accommodated two polypore species, P. adamantinum and P. scaurum; however, phylogenetic studies indicated that these two species were not congeneric within the Hymenochaetaceae and that P. adamantinum formed a clade with Phellinidium noxium. To resolve the relationships among the two species of Pyrrhoderma and other related taxa, specimens from China, Costa Rica, Singapore, and Thailand were studied from both morphological and phylogenetic perspectives. A new genus, Fulvoderma, is erected to accommodate F. scaurum comb. nov., and a new species, F. australe (the generic type). Pyrrhoderma is delimited to include the generic type, P. sendaiense (a later synonym of P. adamantinum); two new combinations, P. lamaënse comb. nov., and P. noxium comb. nov.; and three new species, P. hainanense, P. thailandicum, and P. yunnanense. In addition, an undescribed lineage including several specimens from subtropical and tropical forests in China, Costa Rica, Singapore, and Thailand also nested within the Pyrrhoderma clade. However, as the voucher specimens are sterile or almost so, they are not described. The concept of Pyrrhoderma was emended to also accommodate species bearing resupinate, effuse-reflexed basidiocarps, hymenial or hyphoid setae, and non-subglobose basidiospores. Keys to Fulvoderma and Pyrrhoderma are provided.