Thallus dingy olive-grey or brownish, verrucose, areolate, areolae angular 0.2-0.5 mm diam., separated by deep cracks, surface granular-roughened, spreading in irregular patches, 1-3 cm diam. Fertile verrucae angular-areolate, 0.3-0.8 mm diam. Apothecia lecanorine, 1-3 per verruca, 0.05-0.85(-1.0) mm diam., disc black, epruinose to grey-white pruinose, margins white or grey-white, roughened, eroding-pulverulent. Asci 8-spored. Ascospores uniseriate, oval-ellipsoid, thin-walled, 34-43.3 × 10.2-23.8 µm. Chemistry: K+ yellow → red, C- KC+ red, Pd+ orange. Norstictic and connorstictic acids.