Thompson, J., 1984. American Arctic Lichens: The Macrolichens.
Thallus pendent, to 15 cm long; branching isotomic dichotomous but becoming aniso-tomic toward the apices at times, angles of the main dichotomies varying, rarely with short perpendicular lateral branches; branches even or uneven in diameter, to 0.3 mm diameter, pale brown to grayish, darkening to dark brown or black, dull or shiny; soralia lacking, pseudocyphellae abundant, white, short to elongate fusiform, to 1 mm long, sometimes spirahng arounu the branches. Apothecia rare, to 0.5 mm broad, margin becoming excluded; disk reddish brown, concave to convex; hymenium 36-40 μ; spores 8, hyaline, simple, broadly ellipsoid to sub-spherical, 5.4-7.5 X 4-4.5 μ.
Reactions: cortex and medulla K + yellow turning red (rarely seen), C- , P+ yellow.
Contents: norstictic acid ± traces of con-norstictic acid.
This species occurs on conifers. It is in Europe and also is fairly common in the western U.S. and Canada to Alaska. An outlier of this species is in the Dubawnt Lake area in central northern Canada, unaccountably far from the main North American range.