Sched. Ad Lich. Sel. Exs., 35: 3 (nr. 858), 1970. Basionym: Lecidea sabuletorum f. ternaria Nyl. - Not. Sällsk. Fauna Fl. Fenn. Förh., Ny Ser., 8: 151, 1866.
Synonyms: Lecidea ternaria (Nyl.) Nyl.
Distribution: N - TAA (Arnold, Lich. Exs. 1051: UPS- L-169711).
Description: Thallus crustose, episubstratic, of scattered to confluent, whitish to ash-grey, usually convex or subglobose areoles. Apothecia micareoid, black or blue-black, sessile to substipitate, often tuberculate, 0.15-1 mm across, with a convex to almost globose disc, usually without a proper margin, but sometimes thinly marginate when young. Proper exciple poorly developed but evident in young apothecia, colourless or aeruginose green to olive-green in outer part, of radiating, branched and anastomosing hyphae; epithecium scarcely differentiated from the hymenium; hymenium 60-70 μm high, colourless but often with greenish vertical streaks in lower part, dark aeruginose green in upper part, the pigmented parts K-, N+ purple; paraphyses numerous, 1-1.8 μm thick at mid-level, simple or sparingly branched in upper part, the apical cells to 3 μm wide; hypothecium olivaceous or pale brown in upper part, colourless in lower part, up to 380 μm high. Asci 8-spored, cylindrical-clavate, the I+ blue tholus with a wide, I+ dark blue tube structure that expands towards the top, without a pale axial body. Ascospores (0-)1-3-septate, hyaline, fusiform, straight or slightly curved, 13-22(-24) x 3.5-5 μm. Pycnidia more or less immersed, the wall green (K-) in upper parts. Mesoconidia cylindrical to oblong-ellipsoid, sometimes slightly constricted in the middle, 4-7 x 1.2-2 μm. Photobiont micareoid, the cells 4-7 μm wide. Spot tests: thallus and apothecial sections K-, C-, KC-, P-, UV-. Chemistry: without lichen substances.
Note: an arctic-alpine species growing on plant remains and siliceous rocks near and above treeline; the Italian sample was collected by Lojka between Paneveggio and Predazzo, on a porphyric boulder.