Caloplaca cinnabarina (Ach.) Zahlbr.
Lecanora cinnabarina Ach., Lich. Univ.: 402 (1810).
Thallus rosette-forming to spreading, very closely attached, 0.5-2(-8) cm diam., effigurate, 0.2 mm thick, regularly areolate-cracked, areolae regular, 0.5-1.0 mm diam., separated by deep cracks, margins of areolae noticeably thickened, matt, orange-red, K+ purple, smooth to minutely verrucose-papillate, saxicolous. Apothecia scattered, infrequent, at margins of areolae, solitary rarely 2-5-confluent, sessile, rounded, 0.1-0.6 mm diam., disc plane to subconvex, matt or slightly scabrid, orange, margins minutely crenulate, slightly paler than disc, concolorous with thallus, persistent. Ascospores biseriate, oblong-ellipsoid with rounded ends 2-locular, 8.3-10.2(-12) × 3.5-5(-6.5) µm, septum c. ⅓ the length of spore. Paraphyses septate, branched at apices. Chemistry: Emodin, parietin, xanthorin, fallacinal, parietinic acid.
S: Canterbury, east of the Main Divide on alpine rocks.
Cosmopolitan
