Thompson, J., 1997. American Arctic Lichens: The Microlichens.
Thallus crustose, thin, verrucose-areo-late, verrucules to 0.3 mm, shining, dark brown to black; black hypothallus present. Apothecia small, to 0.7 mm broad; margin and disk black, flat, margin shining, disk dull; exciple black-brown and grading into black-brown hypothecium; epithecium brown; hymenium 50-60 μm, hyaline; paraphyses intricately branched, with constricted septation; asci davate; spores 7-12 x 5-6 μm. Conidia straight, 8-10 x 1 μm.
Reactions: K—, C —, P —, I —.
This species grows on acid rocks in the open. It is rather rare, known from Europe (Scandinavia), Greenland, and northern Canada.