Thompson, J., 1997. American Arctic Lichens: The Microlichens.
Thallus bluish white to bluish gray, tips darkening, sometimes quite brown in strong light; of distinctly discrete radiate lobes, rarely contiguous, the lobes widely forking and chinkily divided into sections transversely, the center of thallus of still radiate, but more convex, and closer areolae; hypothallus usually not visible between lobes. Apothecia immersed in high areolae (compared with sterile areolae), single; margin thick and prominent, of same color as thallus; thalloid margin 1-; disk flat or concave, black, rough, bare; hypothecium 1+ blue; epihymenium olive-brown; hymenium pale, 80-90 µm, 1+ brownish yellow, inspersed; para-physes moniliform, tips 3-3.5 µm; spores 8, ellipsoid. 16-18 x 8.5-10 µm. Conidia 17-19µm.
Reactions: K-,C-, P-, I-.
This species grows on calcareous or noncal-carcous rocks. It is circumpolar arctic, reported from Novaya Zemlya, Spitzbergcn, Greenland. Alaska, and the Northwest Territories.