Thallus crustose, thin, continuous, white, ecorticate. Photobiont Trentepohlia or absent. Ascomata perithecia, solitary, erumpent, black, 0.2–0.4 mm diam, 0.1–0.2 mm high. Perithecial wall not carbonized, up to 100 μm thick; hamathecium hyaline, not inspersed, gel K/I+ blue; pseudoparaphyses simple, 1-1.5 μm thick. Asci cylindrical, I-, 8-spored, uniseriate; ascospores brown, fusiform with subacute ends, 3-5-septate, middle cells largest, constricted at septa, cell walls not thickened, 15-30 x 6-9 μm. Pycnidia black, of two types: 1) globose, 100-200 μm diam. with macroconidia, and 2) globose, 40-60 μm diam. with microconidia. Macroconidia 3-4-septate, bacilliform, blue-green, 12–17 x 4.5–5 μm; microconidia hyaline, simple, filiform, straight, 9–14 x 0.5 μm.
Chemistry. UV-; no substances detected by TLC.
Substrate and Habitat. Corticolous on hardwood trees.
Distribution. Temperate North America and Eurasia; in North Carolina found in the Blue Ridge ecoregion.
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Ezhkin, A.K. & F. Schumm. (2018) New and noteworthy records of lichens and allied fungi from Sakhalin Island, Russian Far East, II. Folia Cryptogamica Estonica55: 45-50.
Harris, R.C. & D. Ladd. (2005) Preliminary Draft: Ozark Lichens, enumerating the lichens of the Ozark Highlands of Arkansas, Illinois, Kansas, Missouri, and Oklahoma. Published by the authors. 249 pp.