Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2002. Lichen Flora of the Greater Sonoran Desert Region. Vol 1.
Thallus: subfoliose and squamulose centrally, forming orbicular patches, up to 5 cm diam, resting on a conspicuous brownish hypothallus lobes: radiating at the periphery, up to 2 mm wide, with ascending, incised margins upper surface: brownish, smooth or shiny, lobulate, lacking isidia or soredia lobules: covering thallus, sometimes sinuose Apothecia: rare, up to 1.5 mm wide, disc: brown, sometimes obscured by secondary lobules; proper exciple: paler; hymenium: I+ blue asci: clavate with apical amyloid tubes, 8-spored ascospores: simple, colorless, ellipsoid, 15-20 x 7-10 µm Spot tests: all negative Secondary metabolites: none detected. Substrate and ecology: on bark World distribution: widespread in subtropical regions, particularly of South and Central America Sonoran distribution: rare, possibly because the lowlands are too dry, up to 1900 m in the subtropical, moist montane forests of the Sierra Madre Occidental of Sinaloa. Notes: This species is previously often confused with Parmeliella mariana (Fr.) P. M. Jørg. and D. J. Gallow., a species which as yet is not known from the North American continent, but is present in Hawaii and the West Indies. That species has apothecia with distinct thalline margin and lacks secondary squamules on the lobe margins.