Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2004. Lichen Flora of the Greater Sonoran Desert Region. Vol 2.

Life habit: lichenized or facultatively lichenicolous Thallus: crustose, warted or areolate cracked; prothallus: sometimes visible between areoles and forming a dark border to the thallus surface: white, pale gray, green, or yellow (darkening to brown in older herbarium material), dull to glossy medulla: white, I- photobiont: primary one a chlorococcoid green alga, secondary one absent Ascomata: apothecial, aspicilioid-lecanoroid or lecideoid, immersed or becoming sessile, immagrinate when young disc: black, somewhat concave to strongly convex margin: with a thalline one or not exciple: thin, +inconspicuous epihymenium: usually with purplish or greenish pigments (N+ red) hymenium: hyaline below, aeruginose or purple to green above; paraphyses: simple or sparingly branched, thick-walled, gelatinously coated and strongly swelling in water, hyaline to violet-brown, without swollen apices but often pigmented (green to black-violet); hypothecium: ochraceous below asci: clavate, Lecanoratype, with an euamyloid tholus and a broad axial body, 8-spored ascospores: hyaline, simple to rarely 1-septate, ellipsoid, without a distinct perispore, +thick-walled Conidomata: pycnidial, immersed; wall: hyaline except for green pigmentation around the ostiole conidia: hyaline, simple, cylindrical, oblong-ellipsoid to short and threadlike, +straight Secondary metabolites: atranorin or usnic acid in the cortex; various depsidones and aliphatic acids in the medulla Geography: arctic/alpine in Asia, Europe, and North America and rarely in Australasia Substrate: non-calciferous rock, and lichen thalli. Notes: Calvitimela differs from Tephromela in that the apothecia are convex and immarginate (e.g. lecideoid), its ascus structure (Lecanora-type instead of Bacidia-type), and the secondary chemistry of its thallus and hymenium. The apothecia are calvitiform ("like a bald spot") when young, a fact that explains the origin of the generic name. The third species, C. testaceoatra (Vain.) Hafellner, with psoromic acid may eventually be found in the region, as it is known from Colorado.