Thallus orbicular, closely attached, to 10 cm diam., corticolous rarely saxicolous. Lobes broad (4-10 mm wide), rounded, somewhat dissected, often crowded, margins entire, sinuous. Upper surface greenish-grey to pale mineral grey, margins tinged brownish or sometimes white-pruinose, shining, smooth, wrinkled centrally, pseudocyphellae small, punctiform, most obvious at margins, becoming sorediate centrally. Soralia derived from pseudocyphellae, clustered at centre, sometimes marginal, punctiform to confluent, soredia fine, dusty, white to grey-white. Lower surface black, rhizinate. Rhizines simple, black or pale brown, numerous, to margins. Apothecia rare, subpedicellate, to 8 mm diam., disc brown, matt, plane, imperforate, margins entire, pseudocyphellate and becoming sorediate, thalline exciple pseudocyphellate. Ascospores broadly ellipsoid, 15-18 × 12-15 µm. Chemistry: Cortex K+ yellow; medulla K-, C+ rose pink, KC+ rose pink, Pd-. Gyrophoric acid and atranorin.