Anthracocytis abscondita (Vánky) McTaggart & R.G. Shivas

Synonyms

Sporisorium absconditum Vánky

Description

Sori destroying the racemes, narrowly cylindrical, 15–30 mm long, 0.5–1.0 mm wide, almost completely hidden by the tubuliform spatheole, with only the tip of the sorus protruding, covered by a thin pale brown peridium that ruptures from its distal part to expose the black granular-powdery mass of spore balls and a long filiform columella. Frequently, all shoots of a plant are infected; occasionally an infected plant may have 1 or several flowering shoots.

Spore balls persistent, subglobose, ovoid, ellipsoidal or irregular, 50–100 × 50–80 µm, dark reddish brown, opaque, composed of tens of spores that separate by strong pressure.

Spores dimorphic. Outer spores subglobose, ellipsoidal to subpolyhedrally irregular, 10.5–13.5 × 8–12 µm, dark yellowish brown; wall uneven, alternating thin and thick, 0.5–2.0 µm, causing darker and lighter areas to be visible; free surface of the outer spores coarsely verrucose; spore profile serrulate on the free surface, smooth on the contact sides. Inner spores subpolyhedrally irregular, about the size of the outer spores, subhyaline to pale yellowish brown; wall thin, to c. 0.5 µm, smooth.

Sterile cells absent.

Hosts
   
Host family: Poaceace
   
Host species: Schizachyrium fragile (R.Br.) A.Camus

Distribution

States & Territories: NT, QLD