Thallus rosette-forming to irregularly spreading, 1-5 cm diam., lobes rather narrow, 1-3 mm wide, sublinear-elongate, highly dissected, margins sinuous, shining, black. Upper surface plane to convex, pale greyish-green to greyish-white or fawnish, shining, waxy, shallowly wrinkled-faveolate and faintly maculate, granular-white-pruinose at lobe apices and margins. Lower surface black, with a narrow, brown, naked marginal zone. Rhizines black, simple, sparse to dense. Apothecia common, pedicellate, 2-4 mm diam., disc dark brown, shining, often pruinose, margins thin, entire, not crenulate, or inflexed, thalline exciple smooth, shining, not verrucose. Ascospores 10-12 × 7-8 µm. Pycnidia numerous, punctiform, black. Chemistry: Cortex K+ yellow; medulla K-, C+ rose, KC+ rose, Pd-. Lecanoric acid and atranorin.