Miriquidica deusta
≡Lecidea fuscoatra var. deusta Stenh., Nov. Sched. Crit. Lich. Suec. 14: 9 (1833).
=Lecidea (Eulecidea) atrofuscula C.W.Dodge, Nova Hedwigia 19: 475 (1971) ["1970"].
Lecidea (Eulecidea )atrofuscula. Holotype: New Zealand. South I., Canterbury, Phipps Peak summit, 1905 m, on exposed rock, B.A. Fineran 2243 – CANU.
Description : Thallus areolate, spreading in irregular patches, 0.1–0.2 mm thick and to 4 cm diam., dispersed on a prominent, black prothallus visible at margins and between areolae. Areolae angular to irregular, 0.3–0.5(–1) mm diam., brown to dark-brown, smooth, plane to subconvex. Apothecia rounded, scattered to crowded, sessile, not constricted at base or subimmersed, 0.4–1(–1.5) mm diam., disc plane, black, matt, epruinose; proper margin black, matt, persistent to excluded. Exciple 40–70 μm thick, ectal zone green-black, inner zone greyish. Epithecium black to olivaceous, 10–13 μm thick. Hymenium 50–60 μm tall, colourless, I+ blue. Hypothecium colourless. Paraphyses branched, not anastomosing, 1.5–2 μm thick, apices to 3 μm diam. Asci 35–40 × 10–12 μm. Ascospores ellipsoidal, 8–11 × 4.5–5(–5.5) μm. Pycnidia immersed. Conidia filiform, curved, (18–)25–35 × (0.5–)0.8–1 μm.
Chemistry : Cortex and medulla K−, C−, KC−, Pd−; containing miriquidic, lobaric and norstictic acids.
S: Canterbury (Phipps Peak, Arthur's Pass, Two Thumbs Ra.), Otago (Rock & Pillar Ra.). On alpine to high-alpine rocks (1280–2540 m) with Lecidea lapicida and Tremolecia atrata (Fryday 2000a: 37; Hertel 2001a: 120). Earlier published as Lecidea atrofuscula C.W.Dodge (Fineran & Dodge 1970: 403; Dodge 1971: 475). Known also from N and NW Europe, Scandinavia, Greenland, Alaska, Canada (Northwest Territories), USA (Nevada), the high Alps of Australia and Russia (Hertel & Rambold 1987; Nimis & Poelt 1987; Rambold 1989, Nimis 1993; Santesson 1993; Sérusiaux et al. 1999; Hertel 2001a; Hertel & Andreev 2003; McCarthy 2003c, 2006; Nimis & Martellos 2003; Andreev 2004; Santesson et al. 2004).
Bipolar
Illustration : Rambold (1989: 122, fig. 11; Foucard 1990: pl. 180 – as Lecidea deustata [sic]).
Miriquidica deusta is characterised by: the saxicolous habit; its shiny brown thallus of discrete areolae with a well-developed epinecral layer; a conspicuous black prothallus; subimmersed apothecia; a colourless hypothecium; ellipsoidal ascospores, 8–11 × 4.5–5.5 μm; and filiform, curved conidia, 25–35 × 1 μm.