New acremonium-like species in the Bionectriaceae and Plectosphaerellaceae

Several molecular studies have demonstrated that species traditionally assigned to the form genus Acremonium are polyphyletic, while Acremonium sensu stricto is a central element of the family Bionectriaceae (Hypocreales). Based on phenotypic characters and molecular phylogenetic analyses, two new Acremonium species, A. moniliforme and A. dimorphosporum , are described. The former is related to Emericellopsis and is characterised by cylindrical conidia, acicular phialides and abundantly formed moniliform hyphae. Acremonium dimorphosporum resembles A. borodinense . It produces dimorphic conidia that are either cylindrical and smooth-walled or ellipsoidal and rough-walled. The new genus Brunneomyces is proposed based on three species, including B. brunnescens (formerly A. brunnescens ), B. europaeus and B. hominis . They are characterised by brown hyphae, sympodial conidiophores and chains of ovoidal to ellipsoidal conidia. Chordomyces albus sp. nov. is characterized by its light-coloured colonies, simple or branched conidiophores, phialides with percurrent proliferations and cylindrical collarettes, and ellipsoidal to cylindrical conidia. The combined analysis of the LSU, ITS, RPB2 and TEF1-α loci supports the inclusion of B. brunnescens , B. europaeus , B. hominis and C. albus in Plectosphaerellaceae.