Distribution: S - Bas (Nimis & Tretiach 1999), Cal (Puntillo 1996).
Description: Thallus crustose, thinly episubstratic, ochraceous, grey-brown or dark brown, consisting of 1-2 mm broad, verrucose to chinky, convex areoles. Apothecia lecanorine, broadly adnate, 0.2-0.5 mm across, with a red-brown to black, slightly to strongly convex disc, and a thin, grey thalline margin. Thalline exciple corticated, rich in algal cells, overlain by an epinecral layer; epithecium red-brown; hymenium colourless to brownish violet, 45-65 µm high; paraphyses lax, mostly simple, the apical cells distinctly swollen, 5-8.5 µm wide, with a red-brown to brown-black cap; hypothecium colourless. Asci 8-spored, narrowly clavate, with a K/I+ blue tholus and a central non-amyloid area, Bacidia-type. Ascospores 1-septate, often constricted at septum, hyaline, ellipsoid, (9-)11-13(-14) X (4-)6-7.5 µm. Photobiont chlorococcoid. Spot tests: thallus K-, C-, KC-, P-, UV-. Chemistry: without lichen substances.
Note: on the top of calcareous boulders, including calciferous schists; probably more widespread in the mountains of the South.