Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2002. Lichen Flora of the Greater Sonoran Desert Region. Vol 1.

Thallus: thickly crustose, areolate areoles: roundish-angular, 1-5 mm broad, convex to almost bullate, up to mm high; marginal areoles: somewhat incised but not effigurate, separated by deep cracks upper surface: strongly gray or bluish gray, pruinose upper cortex: composed of cells c. 6-8 µm diam., 15-25 µm thick medulla: thick, composed of densely intricate hyphae with ± many globular cells (7-12 µm diam.); algal layer: c. 100 µm high; algal cells: 9-15 µm wide lateral and lower cortices: black to dark brown; attached by a central stipe or by several rhizine-like structures (150-350 µm diam. and up to several mm long) originating from the medullary tissue; the outermost hyphae: brown; the central ones: hyaline Perithecia: subglobose, up to 0.4 mm broad; exciple colorless asci: clavate, 60-70 x 14-16 µm ascospores: simple, ellipsoid, 13-20 x 5.5-7.5 µm Pycnidia: laminal, with slightly sunken mouth, up to 300 µm wide conidia: bacilliform, c. 5 x 1 µm Spot tests: all negative Secondary metabolites: none detected. Substrate and ecology: on rock and hard stony soil World distribution: SW North America Sonoran distribution: Arizona, CalIfornia, Baja California Sur, Sonora.