Heterotolyposporium lepidospermatis Vánky
(as 'lepidospermae')

Description

Sori in all flowers of a panicle, completely hidden by the glumes, c. 2.0–2.5 mm long and 1.5 mm wide, filling the flowers with a grey to greyish black mixture of dark spore balls and numerous small hyaline spores (hence the grey colour of the spore mass when dry). Spore mass replacing all central floral organs except the outermost 3 or 4 glumes, powdery except for the agglutinated pointed top and rounded basal part.

Spore balls dark reddish brown, ovoid, elongate, usually irregular, rather permanent, comprising 2–10 (–25 or more?) pigmented spores, 18–40 (–50) × 15–35 (–40) µm, or spores solitary. Coiled groups of sporogenous hyphae not preceding the formation of spore balls.

Pigmented spores reddish to dark reddish brown, variable in form, irregular, subpolyhedral or elongate, with flattened contact sides, hemiglobose or hemiovoid, 12–20 × 6.5–15.0 µm; wall smooth, (0.5–) 1.0–4.0 (–5.0) µm thick, thickest at the angles.

Unpigmented spores between the spore balls numerous, solitary or in groups but not forming balls, globose to broadly ellipsoidal, 5–10 × 4–8 µm, hyaline to very pale yellow; wall c. 1 µm thick, in LM finely punctate (not altering the spore profile), in SEM densely irregularly verrucose.

Germination of the pigmented spores (on WA, at room temperature, after 1 day) resulting in 2–4-celled basidia 15–50 × 2–3 µm. Basidiospores lateral and terminal on basidia, on sterigmata, ovoid, long-ellipsoidal to subfusiform, 6–15 (–20) × 1.0–1.5 (–2.0) µm; hyphae also produced on the basidia, becoming branched and septate. Germination of the colourless spores (under the same conditions) resulting in similar but usually smaller basidia and basidiospores, the basidia often only 2-celled.

Hosts
   
Host family: Cyperaceae
   
Host species: Lepidosperma ensiforme (Rodway) D.I.Morris

Distribution

States & Territories: TAS