Thallus immersed, to verrucose, grey to brownish. Apothecia epruinose or with a dense, citrine yellow pruina on lower side of capitulum. Mazaedium with a faint to strong yellow pruina. Apothecia 0.6-1.9 mm high, very short-stalked and robust or fairly slender with long stalks, 3-20 times as high as width of stalk. All parts of apothecia, except a very thin gelatinous sheet surrounding stalk, I-. Capitulum broadly lenticular, 0.3-0.6 mm diam. Excipulum of weakly anticlinally arranged, slightly elongated, heavily sclerotized hyphae. Hypothecium dark brown, convex. Stalk 0.1-0.3 mm diam., of densely intertwined, dark brown, sclerotized hyphae, or with a pale, not sclerotized central and outer part. The outermost layer is completely translucent, gelatinous and reacts faintly I+ blue. Asci cylindrical with uniseriate spores, or clavate with biseriate spores. Cylindrical asci 34-37 × 3.5-4.5 µm. Ascospores 9-16 × 4-6.5 µm, with distinctive ornamentation of spirally arranged ridges. Chemistry: The yellow pruina of the apothecia consists of vulpinic acid and the thallus contains norstictic acid. Thallus K+ red, Pd+ yellow to orange, C-.