Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2002. Lichen Flora of the Greater Sonoran Desert Region. Vol 1.
Thallus: squamulose, 1-2 cm diam., rosette-forming, lobate lobes: initially rounded and scattered, becoming densely aggregated and imbricate, 0.1-0.5 mm wide (rarely elongating to 2 mm) upper surface: brown when dry, pale brown to deep green when wet, smooth isidia: marginal to submarginal, globose to cylindrical upper cortex: paraplectenchymatous, 30-65 micrometer thick medulla: whitish, loosely interwoven hyphae around Nostoc colonies lower surface: brownish, rhizinate; rhizines: blackish, densely tufted, at base of the lobes Apothecia: rather rare, brown or black, laminal or marginal, up to 1.5 mm diam., sessile to substipitate; margin: pale brown; disc: flat, brown to black, smooth; true exciple: paraplectenchymatous, 85-170 micrometer wide, outer part brown pigmented, not supported by pseudoexciple; hymenium: brown above, K-, colorless below, I+ blue, 100-175 micrometer high; paraphyses: septate, branched, c. 2 micrometer wide, ± swollen at the apices and pigmented; subhymenium: colorless to brown, 115-190 micrometer thick asci: cylindrical, 58-90 x 8-20 micrometer, 8-spored ascospores: fusiform to narrowly ellipsoid, hyaline, (1-) 3-septate, 17-28 x 6.5-9 micrometer Pycnidia: brown to black above, pale below, immersed, up to 0.2 mm diam. conidia: bacilliform or slightly bifusiform, colorless, simple, 2.5-4 x 1 micrometer Spot tests: all negative Secondary metabolites: none detected. Substrate and ecology: on sandstone in moist habitats from near sea level to 800 m World distribution: western North America from southern California to British Columbia Sonoran distribution: rare in southern California in the Santa Monica Mountains and on Catalina Island.