Description: Thallus crustose, thinly episubstratic, greenish grey to pale grey. Apothecia biatorine, rounded or slightly irregular in outline, sessile with a slightly constiricted basis, 0.4-0.7(-1) mm across, with a brown-black, to black, rarely grey-brown, epruinose, flat to moderately convex disc, and an often slightly paler, thin, finally excluded proper margin. Proper exciple well-developed, of branched, radiating hyphae with protruding, capitate terminal cells; epithecium sordid brown, K-, N-; hymenium colourless or brownish, 35-60 µm high; paraphyses simple or sparingly branched in upper part, 1-1.5(-2) µm thick at mid-level, the apical cells slightly swollen; hypothecium colourless, pale sordid brown, N-. Asci 8-spored, clavate, with a K/I+ blue apical dome penetrated by a narrow, K/I– apical cushion surrounded by a narrow, deeply K/I+ blue zone, the wall K/I- but surrounded by an I+ red-brown, K/I+ blue outer layer, the ocular chamber relatively small, Biatora-type. Ascospores 1-celled (rarely 1-septate), hyaline, oblong-fusiform, (9-)12-17(-20) x (3-)3.5-4.5(-5.5) µm. Photobiont chlorococcoid. Spot tests: thallus K-, C-, KC-, P+ orange-red. Chemistry: thallus with argopsin.
Note: an epiphytic species found in shaded and humid situations, with optimum in humid beech forests with Abies alba. It is included in the Italian red list of epiphytic lichens as “Endangered” (Nascimbene & al. 2013c).