Description: Thallus crustose, very thinly episubstratic, whitish grey, continuous, delimited by a black prothallus, forming 2-3 cm wide patches. Apothecia lecideine, numerous, black, c. 0.2 mm across, at first immersed in the thallus, then sessile, with an initially concave, then persistently flat disc and a thin proper margin. Epithecium brown; hymenium colourless, amyloid; paraphyses coherent; hypothecium pale brown. Asci 8-spored, clavate. Ascospores 1-septate, not constricted at septum, brown, 18-20 x 12-13(-15) µm. Photobiont chlorococcoid. Spot tests: Thallus K-, C-, KC-, P-. Chemistry: unknown, probably without lichen substances.
Note: a very poorly known silicicolous species, only known from the type collection from Valle d’Aosta at 1500 m, perhaps belonging to Diplotomma.