Langdonia aristidicola (Speg.) McTaggart & R.G. Shivas

Synonyms

Sorosporium bullatum (Pavgi & Thirum.) Pavgi & Thirum.
Sorosporium consanguineum var. bullatum Pavgi & Thirum.
Sorosporium penuriasorus Durán
Sporisorium aristidicola (Speg.) Vánky
Tuburcinia aristidicola (Speg.) Liro
Urocystis aristidicola Speg.

Description

Sori in some swollen ovaries of a panicle, bullate, fusiform or obovoid with an acute tip, 4–6 mm long, 1–2 mm wide, covered by a thick persistent peridium of pericarp and fungal cells which ruptures irregularly along its side exposing the black semi-agglutinated to granular-powdery mass of spore balls mixed with groups of sterile cells.

Spore balls rather permanent, globose, subglobose, broadly ellipsoidal or slightly irregular, (30–) 40–120 (–140) × (30–) 40–90 (–110) µm, reddish or chestnut-brown to opaque; immature spore balls surrounded by hyaline partly gelatinised hyphae.

Spores 6.0–10.5 × 6–9 µm, light reddish to chestnut-brown, dimorphic. Inner spores polyhedral, thin-walled, c. 0.3–0.5 µm, smooth. Outer spores slightly larger and darker, rounded; free wall subpolyhedral, 1–2 µm thick, including the 0.5–1.5 µm high sparse to moderately dense coarse warts.

Sterile cells in smaller or larger irregular groups; individual cells with 1 or several flattened sides, 3–9 (–12) × 3–7 (–9) µm, yellow or pale smoky brown; wall uniformly 0.3–0.5 µm thick, smooth.

Hosts
   
Host family: Poaceae
   
Host species: Aristida ingrata Domin
Aristida latifolia Domin
Aristida psammophila Henrard

Distribution

States & Territories: NT, QLD, WA

Comments

Langdonia aristidicola differs from other smuts on Aristida spp. by its thick, persistent peridium around the sori and by the presence of groups of sterile cells between the spore balls. It also has rather permanent spore balls composed of slightly dimorphic spores (i.e. outer and inner spores in the balls are different in shape, size, colour and ornamentation) and relatively coarse warts on the free surface of the spores.