Various stages in the life cycle of Phyllactinia guttata. Fig 1. Natural size, on chestnut leaf. 2. Perithecium enlarged. 3. Two asci. 4.Three sporidia. 5.Conidia-bearing hyphae. 6.Conidium germinating.
Microscopically, P. guttata is characterized by large ascomata, long narrow pointed appendages with bulbous swellings at base, 2- or 3-spored asci with large ascospores; the ascomata also have gelatinous cells with tufts of hyphae somewhat resembling hairs.[4] The cleistothecia are capable of dissemination and attachment to new growing surfaces by means of gelatinous penicillate cells.
^Liberato JR. (1997). "Taxonomic notes on two powdery mildews: Phyllactinia chorisiae and Ovulariopsis wissadulae (Erysiphaceae : Phyllactinieae)". Mycotaxon. 101: 29–34.
^Shin H-D, Lee H-J. (2002). "Morphology of penicillate cells in the genus Phyllactinia and its taxonomic application". Mycotaxon. 83: 301–325.