Thallus to 1.5 cm diam., foliose, firmly attached to the rock, forming small contorted, rounded or irregular dark cushions, deeply lobed. Lobes numerous, 1-3 mm wide, radiating, ± extended, repeatedly branched, contiguous, often overlapping, with ascending, ± entire, markedly wavy margins, never swollen. Upper surface dark olive-green to black, ± smooth, matt. Isidia, when present, coarsely globose or squamule-like. Anamorph: no information available. Teleomorph: ascomata apothecia, not frequent, small, scattered or crowded, inconspicuous and often submarginal. Disc 0.3-0.8 mm diam., flat to concave. Asci 8-spored. Ascospores 13-16(-18) × 10-12 μm, ovoid, subglobose or ± cuboid, submuriform, with 4-6 cells.