Triodiomyces triodiae (Vánky) McTaggart & R.G. Shivas


Ustilago triodiae Vánky


Sori in the floral stem and inflorescence, cylindrical, elongate, 200–300 mm long, 1–2 mm wide, sometimes with short adpressed branches on their distal part, the remnants of destroyed spikelets, at first covered by a silvery membrane of host origin which ruptures irregularly in several places and flakes away exposing the dark brown initially agglutinated, later powdery mass of spores.

Spores broadly ellipsoidal or ovoid, rarely subglobose, (8–) 9–12 × 7.0–10.5 µm, yellowish brown; wall c. 0.8 µm thick, moderately densely and uniformly verrucose-echinulate which just affects the spore profile.

Spore germination resulting in 1 (rarely 2) 2–3-celled rather variable basidia initiated from the same point, 8–30 (–35) × 2–4 µm. Basidiospores ovoid to ellipsoidal, several borne laterally and terminally, 4–10 × 1.5–2.5 µm, germinating successively, like yeast cells. Basal basidial cell often producing a long hypha 1.5–2.0 µm diam.

Host family: Poaceae
Host species: Triodia bitextura Lazarides
Triodia microstachya R.Br.


States & Territories: NT, WA


Triodiomyces triodiae has superficial sori on the stems of aborted inflorescences of Triodia spp. which are covered in powdery spore masses. These characters indicate a relationship with Tranzscheliella, and molecular studies may justify its transfer to that genus.