Thallus small to medium, to 4 cm diam., foliose, ± rounded, adnate or subascendent, ± thin, deeply and rather broadly lobate, pale or dark olive-green, lower surface paler, usually greyish to white, ± matt, epruinose, isidiate. Isidia laminal and marginal, numerous, generally covering the thallus, ± globular or squamiform, rather coarse, to 0.5 mm diam., concolorous with thallus or darker. Lobes extended and radiating, repeatedly furcate, lobules rather few, rounded to extended, usually 1.5-3.5 mm broad, free, contiguous or imbricate, ± concave owing to ascending margin which is coarsely undulate, ± entire, often isidiate with age, not swollen. Central parts of thallus often forming a richly isidiate, diffract-areolate crust. Apothecia numerous, often dense and crowded, in some specimens sparse or lacking, laminal and marginal, flattened, subglobose at first, soon sessile with constricted base 0.5-0.7 mm diam., disc plane to subconcave, dark red, matt, epruinose, thalline margin thin to moderately thick, ± entire, smooth or isidiate, not prominent, often ± disappearing, proper margin thin, pale. Ascospores 8 per ascus (sometimes 4-6), monostichous or distichous, usually imbricate, ellipsoid with obtuse or rounded ends or acute ends, submuriform, to eumuriform with 3-6 transverse septa and 1-2 longitudinal ones, 20-30 × 9-10.5(-14) µm. Pycnidia laminal or marginal, immersed to slightly prominent, globose, to 260µm diam.