Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2002. Lichen Flora of the Greater Sonoran Desert Region. Vol 1.

Thallus: foliose, rarely subfruticose, decumbent lobes: rather broad to narrow, c. 0.5-11.0 mm wide; apices: rounded to fusiform, eciliate upper surface: olive-brown to greenish black, rough and occasionally ridged or foveolate, usually dull, occasionally pruinose isidia: sometimes present, flattened; soralia and lobules: absent; pseudocyphellae: sparse, indistinct, immersed cortex: strongly white, prosoplechtenchymatous medulla: white, loosely packed; photobiont: a Trebouxia lower surface: pale brown, attached by simple, black rhizines Apothecia: frequent, marginal to laminal on thallus, at first concave, later becoming convex, pedicellate; margin: prominent, with thalloid rim; disc: imperforate, dark olivaceous brown; exciple: hyaline; epithecium: brown or brownish yellow; hypothecium: hyaline asci: clavate, lecanoral, 8-spored ascospores: simple, ellipsoid to broadly ellipsoid, 6-10.5 x 2.5-5 micrometer; walls: thin, hyaline, not amyloid Pycnidia: laminal or marginal, immersed or emergent and sessile conidia: bifusiform, 5-7 x 1 micrometer Spot tests: all negative Secondary metabolites: cortex with an unknown pigment, medulla with lichesterinic and protolichesterinic acids and 2-3 other low-Rf fatty acids. Substrate and ecology: bark or wood World distribution: temperate/boreal areas of western North America from low altitudes to alpine areas and at intermediate altitudes in central Spain Sonoran distribution: chaarral areas of Baja California and southern California.