Tilletia opaca Syd. & P. Syd.


Neovossia opaca (Syd. & P. Syd.) Vánky


Sori in scattered considerably hypertrophied ovaries, clavate, cylindrical or ovoid with a short acute tip, 10–15 mm long, 3–5 mm wide, green when immature, dark brown at maturity, splitting longitudinally to expose the black powdery mass of spores mixed with sterile cells.

Spores globose or subglobose, rarely broadly ellipsoidal, 18–30 × 17–28 µm, medium yellowish brown to blackish brown, opaque, often with a papilla or a shorter or longer thin hyaline twisted appendage; wall (2.0–) 2.5–3.5 (–4.0) µm thick, including a distinct hyaline sheath and prominent rough warts, 10–16 per spore diameter.

Sterile cells subglobose to ovoid, often collapsed, 16–44 µm diam., subhyaline to pale yellowish brown; wall 1.5–5.0 µm thick, smooth, often with a short hyaline appendage.

Spore germination resulting in aseptate basidia (1, rarely 2 per spore) with short apical branches; each branch with several tubercles on which up to 64 or more basidiospores are produced. Basidiospores acicular, slightly curved, asymmetrical, 33–44 × 1.0–1.5 µm, hyaline, germinating without fusion and giving rise to hyphae producing ballistospores on short sterigmata.

Host family: Poaceae
Host species: Spinifex longifolius R.Br.


States & Territories: WA