Thallus very thin or lacking, dingy greyish-fawn, discontinuous in ± scattered granules, often ± lost in interstices of rock. Apothecia sessile, black, matt, epruinose, ± dispersed, solitary to 1-4-confluent, rounded to irregular, 0.1-2.0 mm diam., at first plane, with a narrow, raised, black proper margin, soon becoming convex and swollen-uneven, immarginate. Epithecium dense green-black, granular, 8-13 µm thick. Hymenium colourless, or very pale greenish, to 45 µm tall. Hypothecium massive, black, heavily carbonised. Ascospores broadly ellipsoid to subglobose, 10.2-12 × 6.8-8.3 µm.