Verrucaria fiordlandica
Holotype: New Zealand. Southland, Fiordland National Park, Lake Te Anau, South Fiord, south side, W of Tutu Burn, 200 m, on siliceous, lakeshore rocks, 10.iii.1993, P.N. Johnson 562. CHR 494631. Isotype – MEL.
Description : Thallus crustose, epilithic, pale pinkish grey-green, matt, smooth, continuous, becoming greenish pink when moist, (50–)80–160(–200) μm thick. Cortex lacking, but uppermost 10–20 μm with few or no photobiont cells. Photobiont green, subglobose to globose, 7–16 × 7–14 μm. Prothallus grey-black, discontinuous. Perithecia numerous, almost entirely immersed with only upper part of excipulum and ostiole exposed. Perithecial apex black, plane to slightly convex, 0.08–0.23 mm diam. Ostiole concolorous or paler, in a shallow depression 30–60 μm in diam. Involucrellum absent. Exciple brown-black, 0.22–0.32 mm diam., 50–80(–100) μm thick near apex, 25–35 μm thick at base. Centrum subglobose to obpyriform, 0.15–0.22 mm diam. Periphyses 30–45 × 1.5–2 μm, simple to sparingly branched. Hymenial gel I+ red-brown. Asci clavate to cylindrical-clavate, 68–80 × 24–30 μm. Ascospores hyaline, broadly ellipsoidal to elongate-ellipsoidal, 19.5–30.0 × 6.0–12.5 μm, contents granular and guttulate.
S: Southland (South Fiord, Lake Te Anau). On lakeshore rocks. Known only from the type locality.
Endemic
Illustrations : McCarthy & Johnson (1995: 505, fig. 3); Malcolm & Galloway (1997: 180).
Verrucaria fiordlandica is an aquatic species, characterised by: the saxicolous (aquatic rocks) habit; its rather thick, pale, epilithic thallus; small, immersed perithecia that lack an involucrellum; and moderately large ascospores.