Thallus orbicular when substrate allows, to spreading, 2-10 cm diam., variously lobed. Lobes ascending at apices, often imbricate, rather thin, margins entire or ± lobulate. Upper surface smooth, shining, yellowish-green (usnic acid) or yellow (in bright sunlight) or greenish-brown (in shade), wrinkled, cracked, undulate, without isidia, soredia, maculae or pseudocyphellae. Lower surface pale creamish or buff to brown, smooth or wrinkled, whitish at margins. Apothecia round to reniform or rarely shallowly lobed, disc red-brown, matt or shining, smooth, margins entire, pale, slightly raised, upper surface areolate-scabrid. Ascospores pale reddish-brown, 3-septate, 17-22 × 5-7 µm. Chemistry: Two chemodemes are present in New Zealand populations. (i): Usnic acid, zeorin, 2 unidentified compounds (?terpenes). (ii): Usnic acid, zeorin, hypostictic and hyposalazinic acids. [See Moroney et al., Phytochemistry 20: 787-789 (1981)].