Moreaua mesomelaenae (Websdane & Vánky) Vánky


Tolyposporium mesomelaenae Websdane & Vánky


Sori in the flowers completely hidden by the floral envelopes. Infection systemic; infected spikelets slightly swollen and paler than those of healthy inflorescences, the fungus deforming and ±destroying the inner floral organ which are covered by the initially agglutinated, later granular-powdery black mass of spore balls.

Spore balls variable in shape and size due to the large variation in spore number, globose, subglobose, ellipsoidal, elongate or irregular, 25–70 (–80) × 20–50 (–60) µm, dull, dark reddish brown, composed of (3–) 10–40 (–80 or more) firmly cohering spores.

Spores flattened on 1 or several sides, with a slightly convex to hemispherical irregularly polygonal free surface, 9.5–15.0 (–18) × 8.0–12.5 µm, in median view subcuneiform, slightly elongate or irregular, 6.5–15 (–20) µm long, light to medium reddish brown; wall of the free surface 2–5 µm thick, irregularly verrucose; wall of the contact sides thinner, 0.5–1.5 µm, smooth.

Host family: Cyperaceae
Host species: Mesomelaena pseudostygia (Kük.) K.L.Wilson
Mesomelaena stygia (R.Br.) Nees


States & Territories: WA