Thompson, J., 1997. American Arctic Lichens: The Microlichens.
Thallus chalk-white to bluish white, radiate-stellate, very thin, the circumference with lobes 2-5 mm long and 0.5 mm broad, centrally areolate, areolae to 0.5 mm broad; cortex opaque, paraplectenchymatous; medulla dense; hypothallus pale and indistinct. Apothecia to 0.5 mm broad, irregular or round, black, bare; proper exciple 35 µm, dark olive-brown, 1+ blue; hypothecium 35-45 µm, indistinct; epihymenium dark olive, K+ yellowish brown; hymenium 70-100 µm, 1+ greenish yellow or reddish brown; paraphyses 2-2.5 µm, not moniliform; asci clavate; spores 8, broadly ellipsoid, 17-19 x 7.5-10 µm, or subglobose, 10-12 x 8-10 µm (Magnusson 1939). Conidia not known.
Reactions: K—, C-, P—.
This species grows on calcareous and non-calcareous rocks. It appears to be circumpolar arctic, occurring on Novaya Zcmlya. in Siberia, on Bear Island. Spitzbcrgcn. Greenland, and in the Northwest Territories.