Description: Thallus crustose, areolate to warted, the marginal areoles somewhatelongate, bright yellow-green. Cortex of minute isodiametric cells; photobiont layer densely inspersed with minute yellow crystals. Apothecia 0.5-1 mm across, with a distinctly yellow-pruinose margin. Exciple blackish brown, strongly thickened at base, of sclerotized, interwoven hyphae; mazaedium present, black; hypothecium convex, up to 225 µm thick in the central part. Asci 8-spored, clavate, formed singly from hooked ascogenous hyphae, dissolving early, with uniseriately arranged ascospores. Ascospores 1-septate and constricted at septum, brown, ellipsoid, 17-22 x 8-10 µm, first smooth but soon with a rimose-areolate surface. Photobiont chlorococcoid. Spot tests: thallus K-, C-, KC-, P-. Chemistry: thallus with vulpinic acid.
Note: a mainly boreal-montane, circumpolar species found on old conifers in humid, open, montane to subalpine forests with frequent fog. It is included as “Regionally Exctinct” in the Italian red list of epiphytic lichens (Nascimbene & al. 2013c).