Ustilago davisii Liro, 1924
Sori form long, dark parallel striae over the leaves, sometimes also the sheaths and culm; they contain a blackish-brown, powdery mass of spores. Spores 7-10 x 8-12 µm, smooth. The fungus is systemic; infected plants usually do not flower.
Glyceria fluitans, maxima, notata.
the spores are appreciably larger than in the much more common U. filiformis.
Brandenburger (1985a: 763), Buhr (1964b), Klenke & Scholler (2015a), Kruse (2019a), Vánky (1994a).