Distribution: N - Frl, TAA, Lomb, Piem (TSB 33000), Lig. C - Tosc, Umb (Ravera & al. 2006, 2006b). S - Cal (Puntillo 1996).
Description: Thallus crustose, whitish, continuous to small granulose-verrucose, sometimes inconspicuous. Apothecia frequent, lecideine, sessile and constricted at base, 0.2-0.7(-1) mm across, very pale when young, then with a flat to slightly convex, reddish brown to dark brown disc (sometimes different apothecia of the same thallus having different hues), and a smooth, rather thin, sometimes finally blackening proper margin. Proper exciple colourless or straw-coloured, often orange- or red-brown at the outer edge, of radiating narrow hyphae, but with 1-2 rows with swollen lumina (to 6 μm wide) at the outer edge; epithecium almost colourless to brownish, K-; hymenium colourless, 45-60 µm high; paraphyses simple, 1-1.5 µm thick at base, the apical cells clavate, up to 3-4 µm wide; hypothecium pale orange-brown and K- in upper part, orange-brown, straw to colourless in lower part. Asci 8-spored, clavate to cylindrical-clavate, the apical dome K/I+ dark blue with a pale, conical-pointed apical cushion (axial mass), the wall I-, but the thin outer gel I+ blue, Bacidia-type. Ascospores 3-7-septate, hyaline, acicular, 30-60 x (1.7-)2-2.5(-3) µm. Photobiont chlorococcoid. Spot tests: thallus K-, C-, KC-, P-, UV-. Chemistry: without lichen substances.
Note: a cool-temperate to arctic-alpine, probably circumpolar lichen found on plant remains and muribund bryophytes on calciferous ground, more rarely on bark, with optimum in upland areas; probably more widespread in Italy, also along the Apennines.
Growth form: Crustose
Substrata: soil, terricolous mosses, and plant debris