Anthracocystis ugandensis (Henn.) McTaggart & R.G. Shivas


Sphacelotheca dolichosora Ainsw.
Sporisorium dolichosorum (Ainsw.) Vánky
Sporisorium ugandense (Henn.) Vánky
Ustilago ugandensis Henn.


Sori destroying the distal part of sterile shoots and transforming them into elongate-linear curved and distorted narrowing bodies 40–110 mm long and 0.5–2.0 mm wide, partly hidden by the uppermost leaf sheath, at first covered by the thin grey host epidermis which disintegrates from the apex to expose a dark brown semi-agglutinated to dusty mass of loose spore balls and spores destroying the parenchymatous host tissues and leaving intact the vascular fascicles as numerous (6 or more) filiform columellae. Sori maturing from their apices where only fascicles of vascular bundles may be present, the basal part of the sori remaining immature.

Spore balls globose, ovoid, ellipsoidal, elongate or slightly irregular, 30–65 (–80) × 30–50 µm, reddish brown, composed of 20–80 (or more?) readily separating spores.

Spores globose, ovoid, ellipsoidal to usually rounded subpolyhedrally irregular, 7–12 × 7.0–9.5 µm, yellowish brown; wall uniformly c. 0.5 µm thick, finely and moderately densely punctate-verruculose; ornamentation scarcely affecting the spore profile.

Sterile cells few or lacking, in small groups; individual cells globose or irregular, 9–14 × 7–12 µm, hyaline; wall c. 0.5 µm thick, smooth.

Host family: Poaceae
Host species: Digitaria diffusa J.Vickery


States & Territories: NSW


Anthracocystis ugandensis has been collected only once in Australia.