TYPE. UNITED STATES. Maine, Aroostook County, St. Francis, on various trees, VIII.1893, Clara E. Cummings & Emma A. Teller s.n. (H, holotype; CUP, FH, MICH, PH, US, isotypes).

Description. Life form: lichenized fungus.

Thallus foliose, adnate, 2-7(-10) cm diam.; lobes flat, short, apices rounded, 1-3(-5) mm wide; upper surface olive-green to brown, often becoming rugulose to lobulate in thallus center. Vegetative diaspores absent. Thallus stratified: upper cortex paraplectenchymatous, 10–16 mm thick, epicortex not pored (SEM); cell walls containing isolichenan; photobiont Trebouxia alga; medulla white. Lower surface flat, smooth, dark brown, lighter at margins; rhizines simple, densely abundant. Ascomata lecanorine apothecia, laminal, sessile to subpedicillate; disk imperforate, concave and becoming convex with age, brown, thalline rim with pseudocyphellate papillae, without maculae. Asci elongate, clavate, Lecanora-type, apically thicked, without an internal apical beak, 8–32 spored. Ascospores simple, globose to ovoid or ellipsoid, thin-walled, hyaline, 15–20 x 8–12.5 μm. Pycnidia laminal, immersed; conidia cylindrical to fusiform, simple, hyaline, 5-8.5 x 1 μm.

Chemistry. Medulla K+ yellow turning brownish, KC-, C-, PD+ red; fumarprotocetraric and protocetraric acids, sometimes atronorin).

Substrate and Habitat. Corticolous on trees.

Distribution. Great Lakes and Appalachian Mountains of eastern North America; in North Carolina found in the Blue Ridge ecoregion.

Literature

Blanco, O., A. Crespo, P.K. Divakar, T.L. Esslinger, D.L. Hawksworth & T.L. Lumbsch (2004) Melanelixia and Melanohalea, two genera segregated from Melanelia (Parmeliaceae) based on molecular and morphological data. Mycological Research 108(8): 873-884.

Hinds, J.W. & P.L. Hinds (2007) The Macrolichens of New England. Memoirs of the New York Botanical Garden No. 96. New York Botanical Garden Press, Bronx, New York. 584 pp.

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