Lecanora rupicola (L.) Zahlbr.
Lichen rupicola L., Mant. Pl. 1: 132 (1767).
Thallus white to grey, pale fawn-buff, rather smooth, areolate cracked, areolae minute, angular, ± convex, often intersected by dark lines of prothallus, forming mosaics on flat rocks 5-8(-10) cm diam. Apothecia sessile, often subinnate at first, 0.2-1.5 mm diam., disc pale brown, white or grey-pruinose, C+ orange, pruina thin to dense, concave to plane to subconvex, margins thin, entire or crenulate, concolorous with thallus. Ascospores ellipsoid, 10-14 × 6-7 µm. Chemistry: Atranorin, chloratranorin, thiophanic and roccellic acids.
S: Otago (Waikouaiti, Mt Maungatua). On rocks, characterised by the pale brown, greyish-white-pruinose discs which react C+ orange; still poorly collected in New Zealand.
Cosmopolitan
