Ustanciosporium appendiculatum

Description

Sori in all the spikelets of an inflorescence, black, powdery.

Spores subglobose, ellipsoidal, or irregularly polygonal, flattened in lateral view, 13.0–18.5 × 10–15 mm, reddish brown, foveolate, smooth in profile, with sporogenous wall material (appendages) attached opposingly on the two flattened sides; wall even, 0.7–1.0 mm thick.

Appendages attached to the spores or detached from them, globose to subglobose, 4–8 × 4–7 mm, pale yellowish brown.

Hosts
   
Host family: Cyperaceae
   
Host species: Rhynchospora exserta C.B. Clarke

Distribution

States & Territories: NT, WA

Comments

This smut characteristically has two conspicuous appendages, one on each flattened side. It also occurs in North America (Fischer, 1953).