Thallus pale greyish-white, 70-90 µm thick, but often composed of several layers overlaying each other, ± wrinkled and irregularly cracked, without soredia or isidia. Apothecia scattered, 1.0-4.0 mm diam., disc plane to subconvex, pale brown-pruinose or sometimes somewhat greyish, dull, margins prominent, thick, brown-black, slightly glossy, occasionally somewhat grey-pruinose. Epithecium olive- or orange-brown, diffuse, upper layer granular, 11-16 µm thick. Hymenium 150-260 µm tall, I+ blue. Ascospores (1-)2-6 per ascus, 1-septate, ± curved, 45-85 × 20-40 µm. Chemistry: KC-, Pd+ orange. Pannarin and zeorin.