[Caloplaca subbracteata (Nyl.) Lettau, more]
Thallus: placodioid, monophyllus, with distinct marginal lobes, up to 2.5 cm in diam. upper surface: yellow or orange, covered with whitish pruina, with scaly schizidia, mainly in the center of the thallus upper cortex: paraplectenchymatous, 20-50 Ám thick including a up to 40 Ám thick epinecral layer medulla: white, 40-135 Ám thick; algal layer: 30-75 Ám thick, clustered lower cortex: absent lower surface: gelatinized, compressed hyhae Apothecia: very rare, sessile, up to 0.75 in mm diam. disc: flat margin: smooth, brighter than disc asci: clavate, 8-spored ascospores: hyaline, simple, ellipsoid to broadly ellipsoid, 9-12 x 4-5.2 Ám Pycnidia: not found Secondary metabolites: anthraquinone pigments. Substrate and ecology: soil and on rhyolite, often over growing mosses and other lichens (e.g. Collema and Catapyrenium species) World distribution: mainly mediterranean-submediterranean in Europe, northern Mexico and southwestern USA Sonoran distribution: found throughout Arizona, southern California, Baja California and Chihuahua, from 200-1700 m.