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, sometimes imbricate lobes: usually subirregular but sometimes sublinear; apices: usually rotund, eciliate upper surface: pale gray to greenish gray, plane to rugulose, sometimes reticulately ridged, smooth, shiny or dull, sometimes maculate, usually epruinose; without or with soredia, pustules or isidia; pseudocyphellae: absent upper cortex: pored epicortex, palisade plectenchymatous medulla: white, loosely packed; cell walls: containing isolichenan photobionts: primary one a Trebouxia, secondary photobiont absent lower surface: black, brown peripherally, plane to sometimes wrinked, attachment by simple rhizines but peripherally erhizinate; cyphellae, pseudocyphellae and tomentum absent Ascomata: apothecial, imperforate, laminal on thallus, orbicular, cup-shaped, sessile; margin: prominent, with thalloid rim; 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 to broadly ellipsoid, 10-14 micro meter long, 6-8 micro meter wide, wall thin, hyaline Conidiomata: pycnidial, laminal or rarely marginal, immersed conidia: bifusiform to rarely bacilliform or fusiform, 7-10 (-15) x 1 micro meter Secondary metabolites: upper cortex with atranorin (rarely usnic acid accessory) and chloroatranorin; medulla some combination of orcinol depsides, beta-orcinol depsides, beta-orcinol depsidones, (higher) aliphatic acids, anthraquinones, or amino acid derivatives Geography: predominantly tropical and subtropical to temperate forests and woodland Substrate: mostly bark or acidic rocks. Notes: This segregate from Parmelia s. lato and Pseudoparmelia sensu Hale (1976c) is characterized by the relatively narrow, eciliate lobes, a pored epicortex, the presence of isolichenin, and simple rhizines. Superficially it is somewhat similar to Paraparmelia, a Southern Hemispheric genus, that is obligately saxicolous, contains Xanthoparmelia-type lichenin, and has smaller spores.