Tilletia pseudoraphidis R.G. Shivas & McTaggart

Description

Sori completely destroying some ovaries in an inflorescence, ellipsoidal, 1.5–2.0 × 0.5–1.0 mm, with floral remnants attached to an acute apex, covered by a persistent perideum, initially green becoming dark brown, rupturing irregularly releasing the black powdery spore mass mixed with sterile cells.

Spores globose, subglobose, broadly ellipsoidal to subpolyhedrally irregular, 20–30 × 18–29 µm, dark brown to opaque, wall c. 2.0 µm thick, with dense, blunt warts, 1.0–2.0 µm high, that in surface view appear as dark rounded or polygonal areas, isolated or 2–several confluent, 15–20 per spore diameter; in optical median view 40–65 on the equatorial circumference; spore profile smooth due to the sheath.

Sterile cells globose, ovoid, broadly ellipsoidal to subployhedrally irregular, rarely with a short papilla, 11–25 × 9–20 µm diameter, subhyaline; wall even, 1–2 µm thick, smooth.

Hosts
   
Host family: Poaceae
   
Host species: Pseudoraphis spinescens (R.Br.) Vickery

Distribution

States & Territories: NT