TYPE. COUNTRY UNKNOWN, Locality unknown, s.d., Persoon s.n. (L, lectotype)
Life form. Lichenized fungus.
Thallus crustose, episubstratic, granular-verrucose, grey-white, more rarely almost endosubstratic and poorly evident. Apothecia short-stalked, pin-like, 0.6-1 mm high. Upper part of stalk dark, but covered in a thick white pruina, lower part pale brown to almost white. Outermost layer of stalk hyaline, consisting of periclinally arranged, strongly gelatinized hyphae: Capitulum 0.2-0.4 mm across, obovoid to obconical, with a well-developed excipulum; inner part of excipulum consisting of periclinally arranged, medium brown hyphae, outer part of irregularly intertwined, swollen and sclerotized hyphae; lower side of excipulum white-pruinose, edge often with irregular vertical splits. Mazaedium well-developed, brown; hypothecium pale brown to colourless, with a concave upper surface. Asci ellipsoid or irregular, formed in chains from hooked ascogenous hyphae, dissolving early, with uniseriate ascospores. Ascospores simple, brown, globose, 4.5-5.5 µm diam., the wall smooth or with irregular cracks. Photobiont chlorococcoid, with rectangular cells (Stichococcus).
Chemistry. Thallus K-, C-, KC-, PD-; very low amounts of atranorin and other unidentified substances.