Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2007. Lichen Flora of the Greater Sonoran Desert Region. Vol 3.

Thallus: endolithic or a reduced zone beneath the apothecia or rarely distinctly areolate and chasmolithic on sandstone or crumbling substrates and then thin and white or pale brown, ecorticate, with scattered to regular stratum of algae above substrate, sometimes densely pruinose on limestone Apothecia: numerous, sometimes sunken in pits in the substrate, usually sessile, circular, (0.2-)0.5-1(-1.3) mm wide, 0.1-0.4 mm thick disc: black (reddish brown when wet), plane or convex, rough, usually pruinose (white to blue-gray) margin: black, thin, raised, entire, persistent, often pruinose true exciple: overall 35-50 µm thick; externally dark brown grading into a colorless interior epihymenium: various shades of brown hymenium: hyaline to pale yellow (orange if thick sections), (70-)90-100(-120) µm tall; paraphyses: conglutinated in pigmentation zone, basally (1-)1.5-2 µm wide, apically swollen and 3-5 µm wide, sometimes in dark brown pigment hoods subyhymenium: hyaline, indistinct, 15-35(-50) µm thick hypothecium: hyaline, 7-10(-12) µm thick asci: clavate, 60-85 x 14-18(-27) µm, 100-200-spored ascospores: hyaline, simple, usually broadly ellipsoid, sometimes appearing globose, 3-5(-6) x 1.5-2(-2.5) µm Pycnidia: not observed Spot tests: all negative Secondary metabolites: none detected. Substrate and ecology: on carbonaceous rocks, rarely on sandstone or on vertical flush surfaces on acidic rocks World distribution: Europe, North America, Asia, Africa, Greenland, and New Zealand Sonoran distribution: common in Arizona, southern California, Baja California, and Sonora. Notes: Sarcogyne regularis is common on carbonaceous rocks throughout the Sonoran area. However, specimens on carbonaceous rocks of the epruinose S. privigna are often misdetermined as S. regularis but the former species differs by having an orange hymenium and a carbonized, undulate or flexuous exciple with joint lines. Specimens of epruinose species may also appear pruinose on carbonaceous or sandstone substrates from run-off or splatter depositing crystals on the discs. Though not seen in Sonoran area, specimens of S. regularis from New Jersey collected on concrete by James Lendemer (ASU!) are completely epruinose and may be another taxon. The type of S. bolleana H. Magn., described from single specimen collected by Bolander, is lost. A specimen determined by Dr. W. Weber as S. bolleana (UPS!) from Colorado and probably seen by Magnusson is heavily pruinose S. regularis with an indistinct white pruinose chasmolithic thallus.