Miriquidica nigroleprosa
≡Lecanora nigroleprosa Vain., Meddel. Soc. Fauna Fl. fenn. 10: 208 (1883).
Description : Thallus of scattered to contiguous areolae. Areolae 0.2–0.8 mm diam., ±rounded, convex often minutely lobate, dark-grey, matt, often sorediate. Soralia 0.1–0.2 mm diam., usually 1 per areole developing from the upper surface, dark blue-grey but abrading whitish and appearing excavate; external cells of cortex and exposed soredia olive-green, N+ red; superficial epinecral layer distinct. Apothecia not seen.
Chemistry : Cortex K−; medulla Pd+ deep-yellow, K−, C−, KC−; containing miriquidic and ±psoromic acids.
S: Otago (Carrick Ra., St Bathans Ra., Hawkdun Ra.). On exposed siliceous rocks. Still very poorly understood here and probably much more widespread in alpine to high-alpine localities. Known also from Great Britain, central and eastern Europe, Scandinavia, Svalbard, Greenland and Russia (Foucard 1990; Santesson 1993; Elvebakk & Hertel 1997; Scholz 2000; Owe-Larsson & Rambold 2001; Coppins 2002b; Nimis & Martellos 2003; Andreev 2004; Santesson et al. 2004).
Bipolar
Illustrations : Foucard (1990: pl. 200 – as Lecidea nigroleprosa); Owe-Larsson & Rambold (2001: 342, fig. 2C−F; 344, fig. 3C−F).
Miriquidica nigroleprosa is characterised by: the saxicolous habit; the dark-grey, sorediate thallus of convex to minutely lobate areolae; and miriquidic and ±psoromic acid in the medulla. It is discussed in detail by Owe-Larsson & Rambold (2001: 346–360).
