Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2002. Lichen Flora of the Greater Sonoran Desert Region. Vol 1.
Thallus: squamulose, often occurring in patches of squamules several cm wide squamules: orbicular to somewhat angulate or lobulate, up to 4 mm diam.; margins: smooth, thickened and upturned upper surface: pale to olivaceous brown or grayish green, dull, not sorediate upper cortex: not developed but with a well developed epinecral layer, often with numerous airspaces (thus giving the thallus a grayish appearance) medulla: paraplectenchymatous; algal layer: 60-120 µm thick lower cortex: 30-40 µm thick, of 2-8 layers of isodiametric or globose cells lower surface: paler than the upper surface, attached by a tuft of hyphae Apothecia: immersed, 1-20 per squamule, with a raised rim when mature; disc: yellowish to reddish brown, up to 1 mm in diam.; epihymenium: yellowish brown, K+ red-violet or rarely K-; hymenium: I+ blue-green, becoming wine-red asci: obclavate; wall: I+ orange but blue after pretreatment with K, >100-spored ascospores: globose to subglobose, 3-8 (-9) x 3-6 µm Pycnidia: no data conidia: fusiform, 3.7-4.3 x 1.2-2.8 µm Spot tests: all negative Secondary metabolites: none detected. Substrate and ecology: on soil, frequently with a high calcium content in deserts and other open, arid habitats World distribution: SW and north central North America to central Mexico, India, Australia, southern Europe, Africa, and the Cape Verde Islands Sonoran distribution: desert areas of Arizona, southern California, Sonora, Baja California, Baja California Sur, Sonora and Chihuahua.