Thallus orbicular to spreading, loosely attached, 5-10(-15) cm diam., corticolous or saxicolous. Lobes rounded, dissected, crowded, margins sinuous, entire, darkening, becoming sorediate. Upper surface greenish-grey to greenish-blue, matt, shining at margins which are often suffused brownish, conspicuously wrinkled, with scattered, punctiform pseudocyphellae towards centre, becoming copiously sorediate. Soredia irregular, coarse, granular, greenish-brown to blackish, derived from pseudocyphellae. Lower surface pale yellowish-buff or buff-brown or whitish, smooth or wrinkled, shining, sparsely rhizinate. Rhizines simple, pale, often to the margins. Apothecia maculae and pycnidia not seen in New Zealand material. Chemistry: Cortex K+ yellow; medulla K-, C+ red, KC+ red, Pd-. Lecanoric acid and atranorin.