Thompson, J., 1997. American Arctic Lichens: The Microlichens.
Thallus thin, varnish-like or dull, smooth to verruculose, pale to white or ashy-greenish, sometimes slightly shiny. Apothecia adnate, to 1.2 mm; margin thin, shining, becoming excluded; exciple radiate, exterior blue-brown, interior pale; disk flat, becoming slightly depressed-convex, black, bare, shining at first, becoming dull; hypothecium pale; epihymenium bluish brown, or dirty blue, K— or K+ distinctly blue; hymenium 60-70 μm, 1+ blue, pale; paraphyses coherent, branching and anastomosing; asci clavate; spores biseriate, hyaline, oblong or rarely ellipsoid, containing oil drops, 13-32 x 5-13 μm.
Reactions: K—, C—, I—.
This species grows on humus and sandy soil. It appears to be circumpolar, as it is known from Novaya Zemlya, Sweden, and Siberia, as well as from Ellesmere Island and at Cape Parry, Northwest Territories.
Thompson, J., 1997. American Arctic Lichens: The Microlichens.
Thallus thin, varnish-like or white. Apothecia black, shining, to 1 mm broad, at first flat and margínate, becoming convex and immarginate; exciple brownish or greenish, outer part radiate, hyaline or pale brownish; hypothecium pale, brownish, 75 μm; epihymenium greenish blue; hymenium 75 μm, upper part blue, lower hyaline; paraphyses simple, coherent, 1-2 μm, only slightly thickened at tip, their upper part blue, then dark brown to tip; asci clavate; spores simple or 1-septate, hyaline, 16-26 x 7-10 μm.
This species grows on moss and humus soils. It is known from Scandinavia and Lawrence Island. Alaska (collected on the Vega Expedition, the specimen checked in the Nylander herbarium).
With its shining, black, convex apothecia and the sometimes simple spores, this species could easily be mistaken for Lecidea assimilata. The presence of the 2-celled spores, and their large size, as well as the pale instead of red-brown hypothecium should eliminate that species from consideration.