Thompson, J., 1997. American Arctic Lichens: The Microlichens.
Thallus membranaceous, continuous or chinky, sometimes ridged, dark brown, brownish gray or greenish gray. Perithecia covered except at ostiole by thalloid tissue, in raised prominences on thallus; exciple pale to dark brown, involucrellum thin, spreading to each side of perithecium; gelatin 1+ red; spores ellipsoid or sometimes reni-form, muriform, brown, with numerous irregularly placed cells, more or less 7-septate tran-versely and 3-septate longitudinally, 42-80 x 21-40 µm.
This species grows on inundated rocks in streams and lake margins. It is known from northern Europe and the Alps, Iceland, Greenland, and rare localities in the Northwest Territories.