Moreaua melanospora (Websdane & Vánky) Vánky

Synonyms

Tolyposporium melanosporum Websdane & Vánky

Description

Sori in the flowers completely hidden by the involucral bracts and glumes. Infected flowers appearing outwardly identical to those of healthy inflorescences, the black granular-powdery mass of spore balls surrounding the destroyed inner floral organs.

Spore balls subglobose, ovoid to elongate or irregular, 40–110 × 30–70 µm, dark blackish brown to black, opaque, composed of 40–140 or more firmly cohering spores.

Spores in median view short to long, subcuneiform or elongate, 8–22 µm long, reddish to blackish brown, in surface view the spores irregularly polygonal, 7–12 × 6.5–10.0 µm; wall of the free surface 2–4 µm thick, irregularly verrucose; wall of the lateral contact sides smooth, thin, c. 0.5 µm, but thicker again on the side facing the centre of the spore balls.

Hosts
   
Host family: Cyperaceae
   
Host species: Mesomelaena graciliceps (C.B.Clarke) K.L.Wilson

Distribution

States & Territories: WA

Comments

Moreaua melanospora has larger darker spore balls with more numerous spores than M. mesomelaenae (see below).