Life habit: lichenized Thallus: squamulose, areolate or subsquamulose, margin slightly lobed or notched, without elongated lobes; prothallus: present, black surface: orange, smooth, without asexual propagules cortex: cellular, 15-30 µm thick, granules absent; medulla paraplectenchymatous, without granules Apothecia: adnate, 0.1-0.6 mm in diam., lecanorine disc: orange, flat, epruinose margin: persistent, flush; thalline margin present or absent, concolorous with thallus; proper margin visible, concolorous with disc parathecium: cellular (paraplectenchymatous) including exciple below hypothecium epihymenium: golden, K+ red, 10%N-, cN-, C- hymenium: hyaline, 60-80 µm tall paraphyses: 2-3 tip cells slightly swollen, with few branches; subhymenium hyaline asci: cylindrical, 8-spored ascospores: hyaline, 2 locules, ellipsoid, 9.5-12.5 x 5.5-7 µm, isthmus 3-4 µm, spore end wall thin Pycnidia: present, mostly immersed, ostiole orange Spot tests: apothecial margin K+ red, 10% N-, cN-; thallus K+ red, 10%N-, cN-, C-, medulla IKI- Secondary metabolites: parietin, fallacinal, emodin, and teloschistin. Substrate and ecology: on non-calcareous or calcareous rocks World distribution: worldwide Sonoran distribution: southern California, Arizona, Baja California, Baja California Sur, western Chihuahua, Sonora, and northern Sinaloa. Notes: See notes under C. squamosa.