Rhodocybella: a new genus in the Entolomataceae

A new genus in the Entolomataceae is described from North America. While in many respects it is microscopically similar to Rhodocybe Maire, Rhodocybella differs markedly from Rhodocybe in three important features. Rhodocybella produces basidiomes with cupulate pendant pilei which are laterally attached, the hymenophore is smooth or produces a few rudimentary lamellar folds, and the hyphae of the pileipellis form knobby to subdiverticulate projections. These features are not found in members of Rhodocybe. Rhodocybella rhododendri has only been collected from the surface of the periderm of living Rhododendron maximum L. stems after periods of heavy rainfall.