Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2002. Lichen Flora of the Greater Sonoran Desert Region. Vol 1.
Thallus: crustose, areolate areoles: 0.3-1.0 mm broad, marginal ones forming radiating flattened squamules up to 2 mm long and 1 mm broad, black below surface: gray prothallus: absent Perithecia: up to 0.3 mm wide, within the central areoles, only the mouth visible as an inconspicuous small projection of the areole; exciple: dark; hymenial algae predominately short, 3-4 µm asci: saccate, 2-spored ascospores: ellipsoid to narrowly ellipsoid, pale brown, muriform to 7-septate transversely, 3-septate longitudinally, 40-45 x 15-20 µm Spot tests: all negative Secondary metabolites: none detected. Substrate and ecology: on acidic rocks, from the deserts to lower montane regions World and Sonoran distribution: apparently restricted to the southwestern in Arizona, Sonora and western Chihuahua.