Thallus orbicular, stellate-radiating, thalli often confluent, to 5 cm diam., closely attached, saxicolous. Lobes very narrow, to 3 mm wide, short, margins crenate, coralloid-sorediate, subascendent or downrolled, often passing into a coarsely wrinkled, warty crust. Soredia granular, grey-white or blackened, on lower surface of lobe apices. Upper surface roughened, wrinkled, ashy grey-white or grey-maculate in parts. Lower surface pale brownish, whitish in parts, rhizinate. Rhizines sparse, brown to black, short. Apothecia small, 1-3 mm diam., sessile, disc concave to plane, black ± grey-pruinose, exciple moderately thick, concolorous with thallus, irregular, waxy. Ascospores oblong-ellipsoid, 12-20 × 5-7.5 µm. Pycnidia rare. Chemistry: Cortex and medulla K+ yellow. Atranorin.