Sporisorium ischaemi-rugosi (J.N. Mishra) Vánky


Sphacelotheca ischaemi-rugosi J.N. Mishra


Sori destroying the entire inflorescence, c. 15–20 mm long and 1–3 mm wide, almost completely enclosed by the uppermost leaf sheaths, at first covered by a thick brown peridium that dehisces irregularly exposing the dark brown semi-agglutinated to powdery mass of loose spore balls, spores and groups of sterile cells, surrounding a stout uniform c. 0.7 mm wide columella with a shortly bifurcate tip protruding beyond the sorus.

Spore balls variable in shape and size, composed of numerous spores that separate very easily.

Spores subglobose, broadly ellipsoidal to usually subpolyhedrally slightly irregular, 11.0–13.5 × 9.5–12.0 µm, yellowish brown; wall uniformly 0.8–1.0 µm thick, densely and distinctly echinulate; spore profile finely serrulate.

Sterile cells in small or large irregular groups or chains; individual cells subglobose, ellipsoidal to slightly irregular, ±collapsed in old specimens, 10–17 µm long, subhyaline to pale yellowish brown; wall 0.5–1.0 µm thick, smooth.

Host family: Poaceae
Host species: Ischaemum rugosum Salisb.


States & Territories: QLD


Two smut fungi, S. ischaemi-rugosi and S. hainanae, have been found on a single collection of Ischaemum rugosum from the Torres Strait. The former destroys the entire inflorescence and has larger spores than S. hainanae, which is restricted to the ovaries.