Thallus dingy grey-white, glaucous-grey or glaucous-yellowish, slightly plicate-rugose to minutely areolate-cracked, shining, varnish-like in parts, in irregular bands or patches 1-2(-4) cm diam., often effuse, black marginal prothallus present or absent. Apothecia scattered, discrete, ± frequent, 0.2-1.5 mm diam., round to irregular, plane to subconvex, discblack, epruinose, matt, minutely verrucose-plicate, margins persistent, thick, black, shining, entire, crenulate or ± striate, Epithecium dense, black, K+ purple-black. Hymenium 80 µm tall, colourless. Hypothecium, thick, dense, straw-yellow to dark brown. Ascospores fusiform-acicular or vermiform, slightly curved, 3-7-septate, 35-65 × 4-5 µm.