A fungal chasmothecium-like structure resembling those of the contemporary members of the Erysiphaceae was found during palynological investigations of Upper Pliocene deposits from Mizerna (borehole Mizerna-Nowa), southern Poland. This chasmothecium-like remain, preserved without any asci, ascospores and mycelium attached, is morphologically most similar to the chasmothecia of modern powdery mildews from the genera Erysiphe, Neoerysiphe, Podosphaera, and Salmonomyces. It differs from hitherto described fossil or modern fungi producing globose, closed ascomata with appendage-like setae. Therefore, a new fossil-genus and species name, Szaferomyces pliocenicus, is introduced for the fossil remains from Mizerna. Contrary to all previous putative fossils of powdery mildews, Szaferomyces pliocenicus nov. gen., nov. sp. is the most probable fossil of spore-producing organs of the Erysiphaceae found so far. However, due to the absence of some diagnostic morphological structures (other than presumptive chasmothecium) and DNA data, the affinity of this fungal fossil remains unclear.