Thallus variable, to 5 cm diam., separate individuals often difficult to distinguish, foliose, rounded, thin, deeply and broadly lobate, bright green or dark olive-green, slightly glossy, epruinose, somewhat swollen when moist, lower surface concolorous or paler, often bluish-grey. Lobes rather few, ± rounded or somewhat extended, rosette-forming and imbricate, ± adnate with ascending, undulate margins, often lobulate 0.5-6 mm broad, surface smooth or isidiate, margins entire or crenate or isidiate, never swollen. Isidia marginal or laminal, numerous, crowded, or sparse, at first globular, then squamiform, seldom terete, concolorous with thallus. Apothecia few or numerous, often absent, laminal, scattered or in part crowded, appressed, not constricted at base, to sessile, never pedicellate, rounded, flattened 1-2(-2.5) mm diam., disc ± plane, pale or dark red to red-brown, slightly glossy or matt, smooth, epruinose, thalline margin thin, granular to lobulate, persistent. Ascospores 8 per ascus, ± distichous, broadly oblong or oval or ovoid or subellipsoid, straight with obtuse or rounded ends, 4-celled to submuriform, (17-)26-34(-47) × (8.5-)13-15(-18) µm. Pycnidia laminal and marginal, visible as pale and usually somewhat prominent dots, ± immersed, subglobose, 170-260 µm diam.