Thompson, J., 1997. American Arctic Lichens: The Microlichens.
Thallus white, thin to moderately thick, smooth to warty, dull, often pruinose, continuous, not fissured-areolate, lacking soredia or isidia.
Fertile verrucae with base constricted, crowded; ostioles black, level to sunken. Apothecia 1 per verruca to 0.7 mm broad; hypothecium hyaline; asci cylindrical; spores 4 (rarely 2, 3, or 5), uniseriate oblique or biseriate irregular, walls double, outer wall 1-3 µm, inner 1-5 µm, smooth, usually with apical wall convex inward, ellipsoid to fusiform, 181-330 X 24-50 µm.