Macalpinomyces ordensis (R.G. Shivas & Vánky) Vánky & R.G. Shivas

Synonyms

Sporisorium ordense R.G. Shivas & Vánky

Description

Sori in some ovaries of an inflorescence, ovoid, 2–5 mm long, 2.0–3.5 mm wide, covered by an initially green, later greenish or yellowish brown peridium of host and fungal origin which ruptures irregularly exposing a dark brown semi-powdery mass of spores mixed with sterile cells.

Spores globose, subglobose to usually ovoid or broadly ellipsoidal, 7–10 × 5–8 (–9) µm, yellowish brown; wall uniformly 0.5–0.7 µm thick, moderately densely verrucose-echinulate; spore profile finely and sparsely serrulate; in SEM spines 0.5–0.7 µm high.

Sterile cells in loose irregular groups (often more than 100 cells), short chains or sometimes solitary; individual cells globose to ellipsoidal or slightly irregular, if in chains they can be flattened on the contact sides, 5–12 (–14) × 5.0–10.5 µm, hyaline; contents homogenous; wall thin, 0.6–0.8 µm, smooth.

Hosts
   
Host family: Poaceae
   
Host species: Brachiaria pubigera (Roem. & Schult.) S.T.Blake

Distribution

States & Territories: NT, WA