Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2002. Lichen Flora of the Greater Sonoran Desert Region. Vol 1.
Life habit: lichenized Thallus: foliose, c. circular in outline, lobate, contiguous, rarely imbricate lobes: sublinear to subirregular; lobe tips: usually rotund, with bulbate cilia upper surface: gray, smooth, plane to rugulose, shiny or dull, maculate or not, usually epruinose; with or without isidia, soredia or lobules; pseudocyphellae: absent upper cortex: pored epicortex, palisade parenchymatous, medulla: white, loosely packed; cell walls: containing isolichenan photobionts: primary one a Trebouxia, secondary photobiont absent lower surface: tan to black, plane to sometimes wrinked, attachment by simple and/or dichotomous rhizines; cyphellae, pseudocyphellae and tomentum absent Ascomata: apothecial, laminal, orbicular, cup-shaped, subpedicellate or sessile; margin: prominent, with thalloid rim; disc: imperforate, pale to dark brown, coronate with black bulbae around inner margin of thalline exciple or ecoronate; exciple: gray or hyaline; epithecium: brown or brownish yellow; hypothecium: hyaline, asci: lecanoral, wall layers apex thickened; apex: amyloid, with wide, axial body divergent towards apex, c. 8-spored ascospores: simple, ellipsoid or bicornute, curved or semilunate, obtuse at the poles; 6-21 x 4-12 µm; walls: thin, hyaline, not amyloid Conidiomata: absent or present, pycnidial, laminal or marginal, immersed or emergent sessile conidia: bifusiform or rarely bacilliform, 5-10 (-15) x 1 µm Secondary metabolites: upper cortex with atranorin (rarely usnic acid accessory) and chloroatranorin; medulla with some combination of orcinol depsides or depsidones, ß-orcinol depsides or depsidones Geography: predominately pantropical and subtropical with a few species extending to temperate forests and woodlands Substrate: mostly bark or acidic rock.