Thallus orbicular to spreading, loosely to closely attached, rather ragged, 8-12(-20) cm diam. Lobes ± linear-elongate, or sometimes rounded, margins deeply indented, ragged, isidiate-lobulate, often ascending, rather fragile. Upper surface bright lettuce-green when wet, pale greyish-green to pale fawn when dry, smooth, undulate to ± wrinkled, matt or shining, with numerous, white, minute, punctiform pseudocyphellae, isidiate, without soredia or maculae. Isidia delicate, flattened, coralloid-branched, rarely ± terete, finger-like, marginal at first then laminal. Medulla white. Photobiont green. Lower surface pale buff to whitish and glabrous at apices, ± uniformly brown-tomentose in older parts. Pseudocyphellae white, scattered, sparse to numerous, sunk in tomentum, to 1 mm diam. Apothecia rare, scattered, subpedicellate, disc dark redbrown, matt, epruinose, concave to plane, to 2 mm diam., margins pale, corrugate-scabrid at first, crenate-coronate with age, exciple massive, pale flesh-coloured, corrugate-scabrid. Ascospores colourless to pale yellowish, oblong-fusiform, 1-3-septate, 30 × 7 µm. Chemistry: Two chemodemes present. (i): 7β-acetoxyhopan-22-ol, hopane-15α, 22-diol, and two unidentified compounds. (ii): 15α-acetoxy-22-hydroxyhopan-24-oic acid, 15α-22-dihydroxy-24-hopanoic acid. (Dr A.L. Wilkins pers. comm.).