Thallus lobate-foliose, spreading, in entangled clones, 5-15(-30) cm diam., loosely attached, corticolous. Lobes linear-elongate, rather narrow, 3-12 mm wide, expanding towards apices, ± subdichotomously branching, complex, imbricate centrally, discrete, ± subascendent at apices, margins entire, slightly thickened below, occasionally with rounded to elongate white pseudocyphellae, truncate or furcate, at apices. Upper surface smooth, glabrous, even or undulate, rarely very shallowly faveolate, ridges smooth not distinct, without isidia, pseudocyphellae or soredia, conspicuously and irregularly white-maculate (×10 lens), dark slate-grey or bluish-grey when wet, pale greenish-grey suffused brownish when dry. Medulla white. Photobiont blue-green. Lower surface pale brownish-pink, wrinkled-striate centrally, ± evenly tomentose to margins, tomentum pale, whitish, short, even, lobe apices sometimes glabrous, whitish, wrinkled-bullate, shining. Pseudocyphellae round to irregular, common, plane, intense white, 0.1-1.2 mm diam., conspicuous. Apothecia very rare, marginal, subpedicellate, 0.5-2.0 mm diam., disc glossy, coriaceous, dark chesnut-brown to black, epruinose, margins pale pinkish-brown, corrugate-striate to verrucose, ± inflexed and obscuring disc at first, becoming ± coronate or denticulate to excluded at maturity, thalline exciple coarsely verrucose-scabrid, minutely tomentose, whitish to dark brownish-pink or red-brown. Epithecium 13-22 µm thick, yellow-brown, of thickened, conglutinate tips of paraphyses. Hymenium colourless, 40-65 µm tall. Hypothecium pale yellowish-brown, 17-30 µm thick. Asci and ascopores not seen. Chemistry: 7β-acetoxyhopane-22-ol and hopane 15α,22-diol.