Musumecia, a new genus of Agaricales, is described to accommodate the new species Musumecia bettlachensis. Based on a combined ITS and LSUrDNA Bayesian, Maximum Likelihood and Maximum Parsimony analysis, Musumecia clearly clusters within the Tricholomatoid clade, where it is sister to Pseudoclitocybe. Musumecia is distinguished from allied genera by a unique combination of macro- and micromorphological characters, including basidiomes with a clitocyboid/hygrophoroid habit, emerging from a fleshy pseudosclerotial mass (pseudosclerotium), decurrent and thick lamellae, a brown darkening of both lamellae and stipe, whitish-cream spore print, elongated non-siderophilous basidia, smooth, acyanophilous and inamyloid basidiospores, and the absence of both cystidia and clamp-connections.