Synonyms: Biatora triptophylla var. coronata (Hoffm.) Rabenh.; Fuscopannaria nebulosa (Hoffm.); Lecanora coronata (Hoffm.) Röhl.; Lepidoma brunneum var. coronatum (Hoffm.) Bagl.; Moelleropsis nebulosa (Hoffm.) Gyeln.; Pannaria brunnea var. coronata (Hoffm.) A. Massal.; Pannaria nebulosa (Hoffm.) Nyl.; Trachyderma nebulosum (Hoffm.) Trevis.
Distribution: N - Ven, TAA, Lomb, Piem, VA (Piervittori & Isocrono 1999), Emil (Fariselli & al. 2020), Lig. C - Tosc, Sar. S - Camp (Aprile & al. 2003b), Bas (Puntillo & al. 2009, 2012), Cal (Puntillo 1995, 1996, Puntillo & Puntillo 2004), Si (Ottonello & al. 2011).
Description: hallus crustose-leprose, consisting of coarse, 0.03-0.1 mm thick, crowded, indistinctly corticate granules often covering large surfaces, sometimes irregularly cracked when well-developed, pale blue-grey to blue-black. Apothecia lecanorine when young, then appearing biatorine, up to 1.5 mm across, sessile or sunken inbetween the granules, with a flat to convex, reddish brown to brown disc, a thin proper margin, and a soon excluded thalline margin often covered in granules. Proper exciple paraplectenchymatous, to 100 µm thick, of radiating hyphae; hymenium colourless, up to 100 µm high, I+ blue-green turning reddish; paraphyses simple, coherent, the upper cells hardly enlarged, with an external brown pigment; hypothecium pale brown. Asci 8-spored, narrowly cylindrical, with a I+ blue tholus and an internal, more intensely I+ blue structure. Ascospores 1-celled, hyaline, ellipsoid, smooth-walled, sometimes thinned at one end, 10-15(-20) x 5-8 µm. Photobiont cyanobacterial (Nostoc, the cells in short clusters). Spot tests: thallus K-, C-, KC-, P-, UV-. Chemistry: without lichen substances.
Note: a mild-temperate early coloniser of clay-sandy soil, especially earth banks along unpaved roads, with optimum in humid areas with siliceous substrata; most frequent in Tyrrhenian Italy, from the lowlands (in very humid areas) to the mountains. See also comment on the genus.