On Protomerulius and Heterochaetella (Auriculariales, Basidiomycota)

Abstract

The taxonomy of Protomerulius and Heterochaetella is revised based on DNA data and morphological evidence, and their type species, P. brasiliensis and H. dubia, are proved to be congeneric. As a consequence, H. dubia and related species, of which four are described as new, are placed in Protomerulius. Heterochaete microspora is also combined in Protomerulius, and the genus concept is redefined to encompass effused species with smooth or spiny hymenophore and monomitic hyphal structure. Psilochaete multifora, gen. and spec. nov. is a distant relative of Protomerulius spp. found in Norway. Heterochaetella cystidiophora is re-collected in Brazil and placed in the synonyms of Heterochaete sanctae-catharinae. This species does not belong to the Protomerulius–Heterochaetella lineage, and it is transferred to Metulochaete, gen. nov.