Thallus firmly attached, forming regular or irregular, complete or partial rosettes, to 15 cm diam., sometimes coalescing and then covering extensive areas of substrate, corticolous. Lobes numerous, radiating, 3-5(-6) mm wide, remaining distinct to centre of thallus, irregularly branched, laterals few, contiguous throughout entire length, becoming compressed and distorted centrally, rarely overlapping, margins sinuous-contorted, entire or occasionally notched, ± thinly blackened, especially centrally, hollow, lower side of internal cavity pale, apices ± suffused-brownish. Upper surface mostly convex, uniformly pale grey, here and there irregularly white-maculate, smooth or subrugose, shining, without isidia or soredia. Perforations frequent, median, mostly on main lobes, 1-1.5 mm diam., ± elevated, becoming low-conical or truncate, rounded or becoming distorted with age. Apothecia frequent, rather widely scattered, rarely 2-3-contiguous, elevated, ± pedicellate, ± turbinate, to 5 mm tall and to 4 mm diam., margins thick, persistent, entire, becoming ± striate-crenulate with age, inflexed, elevated, disc concave to ± plane, dark brown, usually ± bright orange-pruinose, pedicel and margins also ± densely coated in bright orange-red pruina. Epithecium ± red-brown, surface with numerous to few, irregular or ± rectangular orange-brown crystals. Asci 8-spored 130 × 60 µm. Ascospores ellipsoid, 35-43 × 20-23 µm, wall 3.5 µm thick. Chemistry: Atranorin (cortex), norstictic acid [K+ red(crystals), Pd+ orange] and an unidentified orange pigment (K+ purple); apothecial margins K+ purple → black.