Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2002. Lichen Flora of the Greater Sonoran Desert Region. Vol 1.
Thallus: typically areolate-squamulose but sometimes minutely suffruticose, in loosely aggregated patches squamules: swollen, somewhat angulate to lobate, convex, often with flattened tops (especially when young), 0.5-3 mm wide upper surface: tan to dark brownish olive, dull, not sorediate upper cortex: not developed but with a yellow epinecral layer medulla: composed of loosely interwoven hyphae with many hollow areas; algal layer: 75-150 µm thick lower cortex: paraplectenchymatous, 30-56 µm thick, with 3-6 layers of globose cells lower surface: paler than upper surface, attached by short stalk and an umbilicus Apothecia: 1-7 (or more) per squamule, immersed; disc: punctiform, enlarging with age, reddish-brown; epihymenium: brownish, K-; hymenium: I+ wine-red, 105-150 µm high, >100-spored ascospores: globose to subglobose, 4.5-7.6 x 3-4.5 µm Pycnidia: immersed, spherical, up to 400 µm diam. conidia: fusiform, 3.5-4.5 x 1.5 µm Spot tests: all negative Secondary metabolites: none detected. Substrate and ecology: on acidic rocks, including granites in deserts and other open, arid habitats World distribution: SW North America, West Africa, India, central Australia, Sonoran distribution: desert areas of Arizona, southern California, Sonora, Baja California and Baja California Sur.