Tilletia pseudochaetochloae R.G. Shivas & Vánky

Description

Sori in some ovaries of an inflorescence, conspicuous, at first green and fusiform, later brown and obovoid, with a narrow pedicel-like proximal part, 4–8 (–10) mm long, 2–5 mm wide, covered by a pericarp that ruptures longitudinally exposing the blackish brown powdery mass of spores and sterile cells.

Spores globose, ovoid or broadly ellipsoidal, 18–25 (–28) × 18–22 (–25) µm, pale to dark yellowish brown, with densely arranged 2.5–4.0 µm high subacute or blunt warts. Several warts may fuse to form irregularly polygonal areas of different sizes appearing darker in surface view, 6–12 per spore diameter.

Sterile cells very variable in size, 10–50 (–55) µm long, hyaline to pale yellowish brown, often collapsed; wall 1–7 µm thick, finely multilayered, smooth.

Hosts
   
Host family: Poaceae
   
Host species: Pseudochaetochloa australiensis Hitchc.

Distribution

States & Territories: WA

Comments

Tilletia pseudochaetochloae is the only smut fungus known on Pseudochaetochloa, a host in the subtribe Cenchrinae along with Pennisetum and Cenchrus. Tilletia barclayana (Bref.) Sacc. & P.Syd., which occurs on various Pennisetum species, is not known in Australia; it has darker and larger spores (21–30 µm) with lower (1–2 µm) and finer warts (10–15 per spore diameter).