A REVISION OF BALLISTOCONIDIA-FORMING YEASTS AND FUNGI

Ballistoconidia-forming yeasts and fungi were studied morphologically, physiologically and biochemically. Ballistoconidium morphology, presence or absence of clamp connections and teliospores, carbohydrate composition of cell walls, ubiquinones (coenzym Q systems), septal ultrastructure and presence of hyphae were considered usefull characteristics to distinguish genera. Species differentiation was mainly based on morphology, physiology, mol% G + C, in some cases on DNA similarities, and additional characteristics. Three teleomorph genera were discerned, viz. Bulleromyces, Sporidiobolus and Tilletiaria. Five anamorph genera were accepted: Bensingtonia, Bullera, Itersonilia, Sporobolomyces and Tilletiopsis. Ballistosporomyces was considered to be congeneric with Sporobolomyces. Anamorphs of Tilletiales were found to be similar to Tilletiopsis. Conidiogenesis was rather variable and occurred mainly polar. Conidia were formed sessile, on short denticles or on distinct stalks, which may or may not be sympodially branched. Scars were distinct or indistinct, sometimes forming annellations or collarettes. Species in which formation of ballistoconidia was reported to occur, but which failed to form these structures during the present investigation, are treated in this monograph as well. All recognized taxa were fully described, illustrated and discussed.