Thompson, J., 1997. American Arctic Lichens: The Microlichens.
Thallus thin or moderately thick, chinky or areolate, areolae angular, flat or rarely slightly convex, smooth, ashy, white or rarely darker or orange, esorediate, yellowing in the herbarium; a black hypothallus usually present. Apothecia to 1.5 mm broad, innate in thallus or becoming adnate and higher, base not constricted or slightly so; disk flat, black, bare or pruinose; exciple outer part black or bluish black, inner part hyaline; hypothecium variable in thickness, hyaline or with a thin darker brownish layer in center; epithecium greenish; hymenium 55-90 μm, 1+ blue; paraphyses con-glutinate, simple, tips to 4 μm; asci clavate; spores ellipsoid-oblong, sometimes appearing as if 2-celled, 9-15 x 4-7.5 μm.
This species grows on acid rocks in open habitats. It is circumpolar arctic-alpine. In North America it ranges south to Quebec, Colorado, and Washington.
It should be noted that recently Hertel (1984, p. 420) has stated this to be an overvalued norstictic acid-containing chemical strain of L. lapicida. This may well be the final disposition of this “species.” In the meantime it has been retained in this manual.