Thallus (2-)4-6(-8) cm diam., mono- to polyphyllous, ± rounded to irregular, margins incised-ragged or with a few, scattered pinholes, often inrolled or ascending when dry. Upper surface dull, smooth or minutely roughened, dark grey or brown-grey, rarely blackened towards margins, ± pale grey-white centrally, ± white-pruinose centrally and there minutely but consistently radially cracked, often ± areolate above umbo, cracks scarcely noticeable at margins. Lower surface uniformly black, blotchy, greyish at margins and umbo, without rhizines, smooth, ± coriaceous, dull. Apothecia not seen.