Distribution: N - TAA (Nascimbene & al. 2022), Lomb, Piem (Isocrono & al. 2004), VA (Piervittori & Isocrono 1999).
Description: Thallus crustose, episubstratic, up to 2 mm thick, pinkish grey, pale brown or yellowish pink, areolate-verrucose, often sorediate, usually delimited by a dark prothallus. Areoles up to 1.2 mm wide, convex, sometimes bullate, rounded to angular by mutual compression (especially in the central parts of thallus), often sorediate along the margins. Cephalodia arising mainly between the areoles, pinkish or reddish brown, 0.5-1.4 mm wide, with a tuberculate surface. Medulla white, I-. Apothecia rare, arising between the areoles and usually not protruding, lecideine, up to 1 mm across, with a mostly flat, black, epruinose, roughened disc and a thin, brownish black, soon excluded proper margin. Proper exciple poorly developed, brown, of conglutinated, radially arranged hyphae; epithecium brownish black, covered in a granular, black latyer; hymenium colourless, up to 160 μm high, I+ blue; paraphyses conglutinate, slender, branched and anastomosing, not or only slightly tickened at tips, often moniliform in upper part; hypothecium dark brown. Asci 8-spored, elongate-clavate, with a thin, outer amyloid layer and a thickened tholus penetrated by a pore, the sides of which stain I/KI+ deep blue, Porpidia-type. Ascospores 1-celled, hyaline, ellipsoid, 22-27 x 9-15 μm, when young with a thin perispore. Pycnidia black, immersed. Conidia short-acicular, straight, 7-10 μm long. Photobiont chlorococcoid; cephalodia with Stigonema. Spot tests: cortex K-, C+ red, KC+ red, P-; medulla K-, C-, KC-, P-. Chemistry: cortex with gyrophoric acid and traces of lecanoric acid.
Note: an arctic-alpine to boreal-montane, incompletely circumpolar species of weathered, mineral-rich siliceous rocks close to the ground, in areas with late snow-lie.
Growth form: Crustose
Photobiont: green algae other than Trentepohlia (primary); cyanobacteria, filamentous (e.g. Nostoc, Scytonema) (secundary, e.g. in cephalodia)
Reproductive strategy: mainly asexual, by soredia, or soredia-like structures (e.g. blastidia)