Tilletia yakirrae R.G.Shivas, A.R.McTaggart & Vánky

Description

Sori in some ovaries of a panicle, globose to broadly ellipsoidal, 3–4 mm long, 2–3 mm wide, partly hidden by the innermost floral envelopes, covered by a brown smooth leathery peridium that splits longitudinally from its apex exposing the black semiagglutinated to powdery mass of spores mixed with sterile cells. Only the upper fertile floret in a spikelet develops sori; infected spikelets remaining attached to the pedicels.

Spores globose, subglobose or broadly ellipsoidal, 15–25 × 15–22 µm, pale to dark olivaceous brown to dark chocolate-brown or subopaque; wall 2.5–5.0 µm thick (including ornamentation), with cylindrical warts that, in surface view, appear as darker irregularly polygonal spots 5–11 per spore diam., solitary or 2–several confluent and forming short irregular rows, in optical median view 1.5–2.5 (–3) µm high, with flattened or slightly nail-headed tips, 23–41 on the spore circumference.

Sterile cells subglobose, ellipsoidal to subpolyhedrally irregular, 9–40 × 7–30 µm, subhyaline to pale yellowish brown; wall 0.5–10.0 µm µm thick, multilayered when thick, smooth, verrucose or with rudimentary intermediate ornamentation.

Hosts
   
Host family: Poaceae
   
Host species: Yakirra majuscula (Benth.) Lazarides & R.D.Webster

Distribution

States & Territories: WA