Ustilago spinificis F. Ludw.

Cintractia spinificis (F. Ludw.) McAlpine

Sori in spikelets of both male and female plants transforming the inner floral organs into an initially agglutinated, later dusty dark brown mass of spores, hidden by the outermost floral envelopes.

Spores globose, subglobose, ovoid, broadly ellipsoidal, sometimes lacrymiform or lemon-shaped with 1 or 2 subacute ends, often laterally slightly compressed, 4–5 (–5.5) × 3.0–4.5 µm, pale olivaceous brown; wall c. 0.5 µm thick, thinner on the lateral compressed sides, densely verrucose.

Spore germination (on MYP, at room temperature, after 1 day) resulting in 4-celled basidia on which ovoid to elongate-ellipsoidal basidiospores are produced laterally and terminally on sterigmata.

States & Territories: NT, QLD, SA, TAS, VIC, WA