Sporisorium nervosum Vánky, C. Vánky & R.G. Shivas

Description

Sori in all sessile and pedicellate spikelets of an inflorescence, leaving the floral envelopes intact, cylindrical or subfusiform, 6–10 mm long, 0.8–1.0 mm wide, partly hidden by the floral envelopes, covered by a thick pale brown peridium that ruptures longitudinally in several places exposing the blackish brown granular-powdery mass of spore balls surrounding a simple stout filiform columella.

Spore balls globose, ovoid, elongate or slightly irregular, 25–50 (–55) × 20–35 µm, reddish brown, rather permanent, composed of 10–40 (or more?) spores.

Spores rounded, subpolyhedrally irregular, ellipsoidal, elongate, rarely subglobose, 9.5–12.0 (–13.5) × 8–11 µm, yellowish brown, outer spores darker, inner spores paler; wall uniformly thick, 0.5–0.8 µm (excluding the ornamentation); free surface with coarse 0.5–1.0 µm high warts; contact sides and inner spores smooth.

Sterile cells not seen.

Hosts
   
Host family: Poaceae
   
Host species: Sehima nervosum (Rottler) Stapf

Distribution

States & Territories: QLD

Comments

Sporisorium nervosum resembles S. sulcati (M.S.Patil) Vánky: [type on Sehima sulcatum (Hack.) A.Camus, India] which has spore balls measuring 30–70 (–100) × 20–50 µm and including more spores, the spore wall is unevenly thick [1.0–2.0 (–2.5) µm] and thickest at the angles, and the free surface of the spores is very finely punctate.