Fragiliporiaceae, a new family of Polyporales (Basidiomycota)

Fragiliporiaceae fam. nov., a new poroid wood-inhabiting family, is introduced based on the combination of molecular and morphological data, and is typified by Fragiliporia gen. nov. The phylogenetic analysis shows that Fragiliporia fragilis sp. nov. forms a monophyletic group within Polyporales and warrants the introduction of a new fragiliporia clade based on molecular data of ITS + nLSU rRNA gene regions. Combined ITS, nLSU, mtSSU, TEF1 and RPB2 sequence data also demonstrated that the new family Fragiliporiaceae also formed a monophyletic lineage (70 % BS, 57 % BP, 0.99 BPP), and grouped with the phlebioid clade, residual polyporoid clade and core polyporoid clade. Fragiliporiaceae has unique macromorphological characters in having resupinate basidiocarps with very soft tubes when fresh, which become brittle when dry (becoming almost powdery when bruised); a monomitic hyphal system with thick-walled generative hyphae, clamp connections, and frequently H-, W- or Y-shaped hyphae branching from the clamp connections.