Thallus 3-7 (-10) cm diam., initially developing as a cluster of palmate, elongate or flabellate lobes which eventually become suborbicular and overlapping, without a distinct stipe, fragile and brittle when dry, the margin flat to slightly revolute, entire to crenate or lacerate in old thalli. Upper surface smooth to more usually scrobiculate to faveolate, undulating, greyish to dark brown (in wet or dry conditions), maculae and cilia ± absent. Isidia always present, abundant, laminal, mainly developing on ridges of the upper surface, at first simple, glossy and rounded to applanate, soon developing vertical coralloid masses, sometimes substipitate, to 500 µm in height, darker than the thallus. Lower surface scrobiculate, pale orange to brownish, darker towards the centre in old thalli, usually sparsely tomentose. Cyphellae 400-1100 µm diam., abundant, more so towards the margins, round or angular, cupuliform to urceolate with a wide pore, the margin erect, slightly revolute, whitish to cream-coloured, the surface cells lacking papillae. Photobiont Nostoc. Anamorph: hyphae of the lower tomentum can apparently produce small rounded to ellipsoidal conidia. Teleomorph: ascomata apothecia, very rare, 1.5–2.5 mm diam., the disc pale orange brown, flat, with a raised, paler, hairy margin. Marginal hairs small, pale to translucent, fluffy and flexuous.