Thompson, J., 1997. American Arctic Lichens: The Microlichens.
Thallus to 1.2 mm thick at maximum, regularly areolate with 0.5-1.2 mm broad areolae, flat or weakly convex, lead-gray. Apothecia adnate or sunken between the areolae, to 1.6 mm broad; margin nearly absent, present only when juvenile; exciple outer part brownish black, pale within; disk black, dull or slightly shining, flat to hemispherical; hypothecium brownish black with reddish spots to dark red-brown, K+ violet-spotted; epihymenium green-brown to sooty brown; paraphyses simple to partly anastomosing, capitate to 2.5-3.5 μm; asci clavate; spores ellipsoid, simple, hyaline, thick-walled, 10-14 X 6-8 μm.
Reactions: K—, C—, P—, KC —, I — .
This species grows on rocks in open situations. It was described from the Himalayas and then reported by Hertel (198 lc) as also occurring in Iceland and Greenland. The probability is that this is a wide-ranging species which has been identified with other names. It should be possible to find it in the American Arctic in view of its occurrence in Greenland.