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

Squamules: up to 5 mm wide, rounded or elongate, adnate and dispersed to adjacent or slightly imbricate, weakly concave to weakly convex upper surface: bright or greenish yellow, sometimes yellowish brown, dull, epruinose or partly pruinose, smooth or sparingly fissured margin: concolorous with upper side, straight or up-turned, entire or crenulate to lobed upper cortex: up to 50-80 µm thick, composed of thin-walled hyphae with round lumina, containing crystals of lichen substances, sometimes also calcium oxalate medulla: containing calcium oxalate, not lichen substances lower cortex: of mainly periclinally oriented hyphae, not containing calcium oxalate lower surface: white to pale brown Apothecia: up to 1.5 mm diam., laminal, immarginate even when young, black or dark brown, epruinose ascospores: ellipsoid, 14-18 x 6-8 µm Pycnidia: laminal, immersed conidia: bacilliform, 7-8 x 1 µm Spot tests: upper cortex and medulla K-, C-, KC-, P- Secondary metabolite: rhizocarpic acid. Substrate and ecology: on soil in open habitats, from deserts to conifer forests, at 540-2290 m World distribution: North and South America Sonoran distribution: fairly common in Arizona, Baja California Sur, Chihuahua and Sonora.