Ustilago neurachnis Vánky

Description

Sori destroying the inflorescence and distal part of the shoot, fusiform, c. 15 mm long and 3–4 mm wide, hidden by leaf sheaths, later bursting and releasing the dark brown semi-agglutinated to powdery mass of spores and several shreds of host tissues.

Spores solitary, globose, subglobose to broadly ellipsoidal, (6.5–) 7–9 (–9.5) × 6.5–8.0 µm, olivaceous brown, verrucose; wall c. 0.8 µm thick but c. 0.5 µm thick in a small area of the spore; verrucae most pronounced on the thin-walled area; spore profile ±smooth, wavy on the thin-walled area.

Sterile cells absent.

Hosts
   
Host family: Poaceae
   
Host species: Neurachne tenuifolia S.T.Blake

Distribution

States & Territories: NT

Comments

Ustilago neurachnis and U. tepperi are both endemic and restricted to Neurachne. They have similar sori but different spores (Vánky, 2002), those of U. tepperi being echinulate and
13–17 (–18.5) µm long.