Thallus loosely attached, 0.5-2 cm diam., saxicolous. Lobes 0.1-0.2(-0.4) mm broad, flat (the smallest almost subterete), elongate, sublinear, discrete to loosely entangled. Upper surface dark olive-brown to dark copper-brown, slightly paler at apices, ± smooth throughout, slightly wrinkled centrally, dull, subnitid at apices, without isidia. Lower surface dark brown, black at apices, dull to subnitid, without rhizines, attached to substrate by a few, central, loboid holdfasts. Apothecia common, sessile, concave to plane, to 1.3 mm diam., margins entire. Ascospores ellipsoid to subglobose 7-8.5 × 3.5-7 µm. Pycnidia common. Conidia bifusiform 6.5-8 × 1 µm. Chemistry: Cortex K-, HNO3 ± dark blue-green; medulla K+ yellow → orange, C-, KC-, Pd+ red. Protocetraric and fumarprotocetraric acids.