Stollia bursa (Berk.) McTaggart & R.G. Shivas

Synonyms

Macalpinomyces bursus (Berk.) Vánky
Sphacelotheca bursa
(Berk.) Mundk. & Thirum.
Sporisorium bursum (Berk.) Vánky
Tolyposporium bursum (Berk.) McAlpine
Ustilago bursa Berk.

Description

Sori in some hypertrophied ovaries of an inflorescence, at first green and elongate, later greenish or yellowish brown ovoid or subglobose bodies 3–4 mm long, gradually narrowed into a short pedicel, abruptly contracted into an acute yellow 1.0–2.5 mm long apex (the remnants of the distal part of the caryopsis). Sori covered by a peridium that ruptures irregularly to expose the dark brown powdery mass of spores mixed with loose irregular groups of sterile cells. Peridium composed of an external layer of host origin and an internal often incomplete layer of fungal origin. Columella absent, but a white mass of fungal cells filling the pedicel and basal part of young sori, giving rise to the internal layer of the peridium and probably also the spores and groups of sterile cells.

Spores in irregular many-spored groups when immature, later solitary, globose, subglobose to broadly ellipsoidal, 9–12 (–13) × 8–11 µm, light brown; wall uniformly c. 0.8 µm thick, sparsely but distinctly echinulate; spines c. 1 µm high.

Sterile cells subglobose, ovoid to somewhat irregular, smaller than the spores, 6–8 (–10) µm long, hyaline, with granular contents and a smooth c. 0.5 µm thick wall.

Hosts
   
Host family: Poaceae
   
Host species: Themeda arguens (L.) Hack

Distribution

States & Territories: WA

Comments

McAlpine (1910: 186) transferred Berkeley’s Ustilago bursa to Tolyposporium, based on three Australian collections on Anthistiria ciliata L.f. [= Themeda quadrivalvis (L.) Kuntze]. Two of these specimens represent what is now known as Anthracocystis walkeri Vánky. The third, from Walsh River, Queensland (duplicates in BRIP 280 and VPRI 2988), occurred on Themeda arguens (Bailey, 1892, as Ustilago bursa on Themeda frondosa) and represents Anthracocystis themedae-arguentis Vánky. The presence of Stollia bursa in Australia can be confirmed from one specimen, collected in Western Australia on Themeda arguens. Stoll et al. (2005) considered that DNA sequence analysis clearly indicated that S. bursa belonged to Sporisorium as proposed by Vánky (1988).