Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2007. Lichen Flora of the Greater Sonoran Desert Region. Vol 3.
Life habit: lichenized Thallus: crustose, areolate to sub-squamulose, without elongated lobes; prothallus: absent surface: gray, smooth, without asexual propagules cortex: cellular, thin, without granules Apothecia: adnate, 0.5-0.8 mm in diam., lecanorine disc: brown, flat, epruinose margin: persistent, flush; thalline margin present, concolorous with thallus; proper margin not visible parathecium: cellular (paraplectenchymatous) including exciple below hypothecium epihymenium: brown, K-, H-, 10%N-, cN-, C- hymenium: hyaline, 60-75 µm tall paraphyses: with 1-2 tip cells swollen, with few branches or with some branching; subhymenium hyaline asci: cylindrical, 8-spored ascospores: hyaline, 2 locules, ellipsoid, 10-12.5 x 5.5-7 µm, isthmus 4-5.5 µm, spore end wall thin Pycnidia: not observed Spot tests: apothecial margin K-, H-, 10% N-, cN-, C-; thallus K-, H-, 10%N-, cN-, C- Secondary metabolites: none. Substrate and ecology: on bark World distribution: North America Sonoran distribution: Arizona. Notes: Caloplaca dakotensis is distinguished by the nonsorediate thallus, and the large oval paraplectenchymatous cells in the upper parathecium. Caloplaca diphasia and C. obscurella both have similar oval paraplectenchymatous cells in the upper parathecium but C. obscurella has soredia and C. diphasia has a continuous lighter gray thallus and larger apothecia.