Baeospora occidentalis, a new snowbank agaric from western North America

Baeospora occidentalis is described as a new species associated with melting snow in montane coniferous forests of the western USA. The species is springfruiting and is characterized by a long tapering pseudorhiza covered with white basal rhizomorphs which extends deeply into the needle litter or woody debris. It possesses a multiallelic, tetrapolar mating system. Monokaryotic mycelia produce arthroconidia.