Urocystis stipae McAlpine

Description

Sori in leaves, leaf sheaths and stems, forming dark elongate streaks, at first covered by the epidermis which ruptures longitudinally exposing the blackish brown granular-powdery mass of spore balls.

Spore balls globose, subglobose, ellipsoidal, oblong or slightly irregular, 23–45 × 20–33 µm, light golden brown, composed of (1–) 2–8 (–9) spores and a complete or almost complete layer of sterile cells.

Spores globose, subglobose, ellipsoidal, elongate or irregular, with 1 or several flattened sides, 12.0–18.5 × 9.0–13.5 µm, golden brown.

Sterile cells variable in shape, 5.5–12.0 µm long, pale yellowish brown; wall 0.5–1.5 µm thick, collapsed in old specimens.

Hosts
   
Host family: Poaceae
   
Host species: Austrostipa drummondii (Steud.) S.W.L.Jacobs & J.Everett
Austrostipa scabra (Lindl.) S.W.L.Jacobs & J.Everett

Distribution

States & Territories: NSW, VIC

Comments

Urocystis stipae is one of three smut fungi that produce sori in the leaves and stems of Austrostipa spp. in Australia. The others, Fulvisporium restifaciens (D.E.Shaw) Vánky and Tranzscheliella hypodytes (Schltdl.) Vánky & McKenzie, are far more common.