Asterobolus: a new parasitic hyphomycete with a novel dispersal mechanism

The genus Asterobolus is proposed for an undescribed hyphomycete characterized by multicelled, star-shaped conidia forcibly discharged by a downfolding of the radiating appendages and rupture of the sporogenous cell. Asterobolus gaultheriae sp. nov. is the causal agent of a leaf spot of Gaultheria shallon Pursh. The fungus also infects species of Vaccinium, Pteridium, Malus, and Menziesia. Sclerotia were observed only on Gaultheria and infections of other hosts were found only near infected Gaultheria. In addition to the star-shaped conidia, a Gliocladium-like conidial stage was also observed in cultures of the fungus.