Taxonomical position of polypore Dichomitus albidofuscus: Donkioporia albidofusca comb. nov.

Taxonomy of the rare polypore Dichomitus albidofuscus is revised and discussed. Examination of extensive herbarium material as well as rDNA sequencing revealed that this species is alien to the heterogenous genus Dichomitus but is very similar to another rare polypore, Donkioporia expansa. Consequently, a new combination Donkioporia albidofusca is proposed. An emended description of Donkioporia is provided to also accommodate annual species with light yellowish brown vegetative hyphae with arboriform branched ends.