Abstract
Examination of herbarium specimens and newly collected basidiomes combined with molecular analyses of representatives of several different taxa has uncovered the existence of a new Phaeocollybia species from Washington, Oregon, and California. Phaeocollybia pleurocystidiata represents the first species described from the United States and Canada known to exhibit a vernal phenology. Morphological and molecular comparison of the type of P. carmanahensis with newly collected material reveals it to be conspecific with the earlier named P. oregonensis; an emended description of P. oregonensis is provided.