Thallus thick, chalky white or creamish-white, areolate-cracked or ± continuous or irregularly cracked to verrucose-uneven or plicate-rugose, surface smooth coriaceous, to ± roughened-tartareous, spreading in irregular often coalescing patches, 2-5(-20) cm diam. Fertile verrucae round to irregular, ± hemispherical, apex flattened or ± eroded and level with thallus surface, 1-8 mm diam., with 1-5 apothecia per verruca. Apothecia immersed, disc black or dark brown, epruinose, round to irregular and becoming ± stellate, 0.2-1.0 mm diam., often absent. Asci clavate, 4-spored. Ascospores uniseriate, oval 61-91.3(-115) × 30-43.5 µm. Wall 4-5 µm thick. Chemistry: K+ yellow → red, C-, KC+ red, Pd+ orange. Norstictic and connorstictic acids.