Cicinnobolus cesatii de Bary, 1870[2][3] Ampelomyces quisqualis is an anamorphic fungus that is a hyperparasite of powdery mildews.

These mycoparasites can live up to 21 days on mildew-free host plant surfaces, attacking powdery mildew structures as soon as they appear.

[5][6] Ampelomyces quisqualis has been shown to attack more than 64 species of powdery mildew in the genera Brasiliomyces, Erysiphe, Leveillula, Microsphaera, Phyllactinia, Podosphaera, Sphaerotheca, and Uncinula.

Hyphae, conidiophores and immature cleistothecia can all be infected, the mycoparasite entering through the cell walls, and the previously transparent tissues turning milky-white.

[7] Ampelomyces quisqualis is up to 98% effective in controlling the powdery mildew Erysiphe cichoracearum on both young and old leaves of cucumber.