Thallus foliose, lobate, loosely attached, 5-12 cm diam., saxicolous. Lobes variable, broad, rounded, to 5 mm diam., to narrow (1-2 mm diam.) and ± strap-like, often densely imbricate, margins entire, subcrenate, suffused brownish, apices rounded or slightly incised. Upper surface yellowish-green, smooth, shining at margins, wrinkled-cracked centrally, moderately to densely isidiate, maculae, pycnidia and soredia absent. Isidia laminal, often forming a dense ± areolate crust, slender, terete, simple, becoming coralloid-branched, to 1-5 mm tall. Lower surface black, with a narrow, brown, naked marginal zone, smooth and shining at margins, matt and wrinkled centrally. Rhizines sparse, simple, black or brown. Apothecia infrequent, sessile, 2-6 mm diam., deeply cupuliform at first, then shallowly convex with age, disc smooth, red-brown, imperforate, margins conspicuously isidiate, thalline exciple wrinkled, shining, becoming isidiate with age. Spores 8-10 × 4-5 µm. Chemistry: Cortex K-; medulla K+ yellow → red, C-, KC+ red, Pd+ orange. Salazinic and usnic acids.