Molecular phylogeny reveals Megacollybia virosa is a Cantharocybe

Nuclear LSU rDNA sequence analysis unequivocally places an agaric currently designated as Megacollybia virosa in Cantharocybe. Based on this molecular evidence, Cantharocybe virosa comb. nov. is proposed. This transfer results in the recognition of a third distinct species of Cantharocybe. The collections from India form the first record of the genus outside the North American continent. Phenetically, C. virosa shares with the type species of the genus, C. gruberi, the clitocyboid habit, distinct cheilocystidia, convex pileus with an inrolled margin, subdecurrent to decurrent lamellae, thickset stipe, ellipsoid, thin- walled, hyaline, smooth and inamyloid basidiospores, clamped hyphae, subregular to regular lamellar trama, a cutis-type pileipellis disrupted to form trichodermal patches, pileipellis hyphae with plasmatic pigment, and cystidioid terminal cells. A key to the known species is provided.