Strigula australiensis
Description : Thallus crustose, epilithic, effuse to determinate, continuous to sparingly cracked, greenish grey to pale grey-brown, smooth to minutely and irregularly uneven, matt, ecorticate, 30–60(–100) μm thick. Prothallus not apparent. Perithecia semi-immersed to ⅓-immersed, usually solitary, occasionally paired, moderately to very numerous; apex plane or convex; ostiole conspicuous or in a shallow depression, 60–100 μm wide. Involucrellum greyish black in surface view, brown-black to black in section, dimidiate or extending to exciple base-level, 0.32–0.58 mm diam., 30–60 μm thick towards apex, 60–90 μm thick at base. Centrum broadly ovate to depressed-ovate, 0.2–0.32 mm diam. Exciple uniformly hyaline to very pale brown, 15–25 μm thick. Paraphyses simple to sparingly branched (especially at apices), not anastomosing, septate, long-celled, 1–1.5 μm thick, cells often with oil bodies. Periphyses absent. Asci fissitunicate, 8-spored, broadly to elongate-cylindrical, 68–93 × 17–22 μm, apex rounded 3–6 μm thick, with an ocular chamber 1–3 μm broad and 1–2 μm tall, convex to tuberculate, walls and apex IKI−, ascoplasm IKI+ red-brown. Ascospores colourless elongate-ellipsoidal to elongate-fusiform, submuriform with 7–11 transverse septa, each loculus with 0–2 longitudinal or diagonal septa, 23–36 × 7–11.5 μm. Pycnidia of two types: (1) 60–100 μm diam., black above, colourless below, with a simple conidiogenous layer and fusiform microconidia 2–3 × 0.8 μm; (2) 0.19–0.24 mm diam., black above, colourless below, with narrowly cylindrical or narrowly ellipsoidal, submuriform macroconidia, 19–30 × 6–9 μm, with convex to acuminate, gelatinous appendages at their apices.
S: Nelson (Brook Stream, Lookout Track). On damp, shaded forest rocks. Known also from Queensland and Lord Howe I. (McCarthy 1995e, 2003c, 2006).
Australasian
Illustration : McCarthy (1995e: 325, fig. 1).
Strigula australiensis is characterised by: a silvery grey, epilithic thallus, moderately large perithecia and submuriform ascospores and macroconidia which, because they are broader than any other taxa, are also more abundantly septate.
