Thallus: forming continuous patches or mosaics, clearly delimited, rimose, often thick and uneven, the areoles flat to slightly convex, white-grey or sometimes deeper grey to green- or brown-grey, the surface ± smooth. Prothallus whitish or little evident, but grey-black when between other thalli of this species. Soredia, isidia and cephalodia absent. Photobiont trebouxioid. Anamorph: conidiomata pycnidia, immersed in the thallus, walls hyaline but brown around the ostiole. Conidiogenous cells elongate-ampulliform, proliferating percurrently with broad collarettes. Conidia 14-25 × ca 1 μm, thread-like to curved, hyaline, aseptate. Teleomorph: ascomata apothecia, 0.5-2 (-3) mm diam., immersed to slightly raised, arising singly or juxtaposed. Thalline exciple entire and crenulate to flexuose or convoluted, not extending above the thallus surface. Discs pink to brown, flat to convex, densely pale grey to blue-grey pruinose. Epithecium pale brown to dark olivaceous brown, interspersed with crystals not dissolving in K. Hymenium 80-90 μm tall, I+ blue. Interascal tissue of sparsely branched paraphyses 2-3 μm diam., the apices swollen to ca 3.5 μm diam., not or slightly thickened, hyaline. Asci elongate-clavate, the apex strongly thickened with a K/I+ blue apical dome and a broad K/I– apical cushion, outermost gelatinous coat K/I+ blue, 8-spored. Ascospores (8-) 9-14.5 (-15) × 5.5-7 (-7.5) μm, ellipsoidal, rounded at the apices, hyaline, aseptate, fairly thick-walled, smooth, without an epispore, gelatinous sheath or appendages. Chemistry: thallus C–, K+ yellow, medulla UV+ yellow, apothecial disc C+ yellow, Pd–, UV+ pale orange (atranorin, chloratranorin, sordidone, eugenitol, roccellic and thiophanic acids).