Sporisorium modestum (Syd.) H. Scholz


Sphacelotheca modesta (Syd.) Zundel
Ustilago modesta Syd.


Sori in all flowers of an inflorescence, occupying the ovaries and the basal part of the inner floral envelopes, 1.5–2.5 mm long, 1.0–1.5 mm wide, apiculate, covered by a delicate yellowish peridium that flakes away exposing the blackish brown, initially agglutinated later dusty mass of spores mixed with sterile cells and a short (0.5–1.5 mm) irregular central columella.

Spores solitary at maturity, globose to broadly ellipsoidal, 11–14 × 9–12 (–13) µm, olivaceous brown, rather densely echinulate; spines thin, acute, 0.5–1.0 µm high.

Sterile cells in irregular groups; individual cells globose to ellipsoidal, 5.5–10.0 µm long, hyaline, thin-walled (c. 0.5 µm), smooth.

Host family: Poaceae
Host species: Enneapogon avenaceus (Lindl.) C.E.Hubb


States & Territories: NT