Thompson, J., 1997. American Arctic Lichens: The Microlichens.
Thallus ashy white, not radiate, of verrucose areolae 1-1.6(-2) mm broad, the areolae irregular, the base narrowed, the surface with secondary fissures when large; a whitish hypothallus visible on rare specimens. Apothecia single or 2 or 3 per verruca; margin broad or narrow, of same color as thallus; thalloid margin 1+ blue; disk black, to 1.6 mm broad, usually with a thin fissure between it and the margin, concave; hypothecium 1+ greenish blue; epihymenium dark olive; hymenium 100-120 µm, 1+ yellowish brown; paraphyses 1.5-2 µm, tips moniliform and 3-3.5 µm; asci clavate; spores 8, broadly ellipsoid to subglobose, 17-25 x 12-16 µm. Conidia not known.
Reactions: K—, C—, P—, I—.
This species grows on calcareous or noncalcareous rocks in the open. It is circumpolar arctic and known from Scandinavia, Greenland, the Northwest Territories, and Alaska.