Thallus immersed in substratum. Photobiont: . Apothecia short to middle-sized, 0.8-1.2 mm high, 18-30 times as high as width of stalk. Stalk 0.03-0.05 mm diam., shining, black, distinctly flexuous. Capitulum obconical to obovoid, with a ± well-developed pruina on lower side (pruina tends to be citrine yellow in young apothecia and reddish-brown in older ones. The yellow pruina consists of K-, granular crystals, while the reddish-brown pruina dissolves in K and yields plate-like or feather-like, violet-red crystals. The degree and type of pruinosity varies between collections and both types of pruina are found in the same apothecium). Excipulum 0.11-0.15 mm diam., well-developed and slightly bell-shaped in longitudinal section. Hypothecium minute with slightly convex surface. Asci catenulate, of variable shape, cylindrical with uniseriate spores or more irregular and with irregular and with ± biseriate spores, mature asci 9.5-12.5 × 1.8-2.7 µm. Ascospores spherical, sometimes broadly ellipsoid, spherical spores 2.9-3.5 µm diam., with smooth walls or sometimes with few, irregular cracks. Chemistry: The citrine yellow pruina contains vulpinic acid.