Thallus in irregular patches, to 5 cm diam., grey-white, minutely granular-verrucose or cracked, granules often superficially blackened, flatened, 0.2 mm diam., congested, often obscured by apothecia. Apothecia numerous, often obscuring thallus, sessile, 1-6-confluent, disc 0.5-0.8 mm diam., black, matt, epruinose, margins entire, or distinctly flexuose-contorted, persistent, black, often ± shining. Epithecium bluish- or greenish-black, to 10 µm thick. Hymenium pale yellow or brownish, 90-110 µm tall. Hypothecium thick, brown-black. Ascospores ellipsoid, 8-10 × 5-6 µm.