Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2004. Lichen Flora of the Greater Sonoran Desert Region. Vol 2.
Thallus: foliose, single lobed attached by a single umbilicus and with (13-)15-24(-30) mm wide lobes upper surface: grayish or bluish gray, epruinose with epinecral layer consisting of air filled hyphae upper cortex: 50-230 µm thick, hyaline with the outermost c. 20 µm brown medulla: 160-250 µm thick, consisting of of filamentous hyphae lower cortex: 50-80 µm thick, with the outermost 10-20 µm brown to dark brown lower surface: light brown to occasionally brown, usually smooth but occasionally verrucose, rugose or slightly reticulate Perithecia: broadly obpyriform to globose, 280-420 µm high and 300-370 µm wide, with hyaline exciple which is brown in the uppermost part, ostiolum level with the surface asci: clavate, 8-spored ascospores: simple, hyaline, (11-)12-15(-17.5) x (5-)6-7(-8.5) µm Pycnidia: not found Spot tests: all negative Secondary metabolites: none detected Substrate and ecology: on rocks of different types, often on boulders and rocks which are partly overgrown with mosses, occasionally in seepage World distribution: Cuba, Mexico, and U.S.A. Sonoran distribution: Arizona at intermediate elevations. Notes: Dermatocarpon tenue resembles D. americanum, but it has a light brown lower surface and an epruinose upper surface.