TYPE. JAPAN. Rikusen [Iwate Prefecture, Rikuzentakata], “Ad corticem arboris.” 1913, Yasuda 52 (TURK-V 4416, holotype).

Description. Lichenized fungus.

Thallus crustose, continuous, pale gray, thick, verrucose, covered with thick, cylindrical isidia, 0.1-0.3 mm across and up to 1.2 mm long, the isidia sometimes growing out of large, rounded verrucae. Prothallus distinct, paler than thallus, often zoned. Ascomata lecanorine apothecia, often absent, 1.0-3.0 mm diam.; disk yellowish pink, epruinose; margins thick, verrucose to isidiate, sometimes radiately striate, rarely smooth. Hymenium hyaline, 175-270 μm; hypothecium hyaline, 70-110 μm, amorphous; proper exciple distinct, 35-70 μm thick; amphithecial medulla thick, lax or filled with small crystals; cortex variable, either very thick throughout or thin laterally and more than 100 μm thick at base, or rarely, uniformly thin; algal layer usually in radiating clumps in margin, interdigitating with thickenings in cortex, with frequent, almost continuous clumps below the hypothecium. Asci 6-8-spored; ascospores often aborted, simple, hyaline, 36-65 x 20-36 μm.

Chemistry. Thallus cortex and apothecial disks C+ pink, KC+ red; medulla C-, KC-; gyrophoric acid.

Substrate and Habitat. On granitic rock or bark (Quercus, Acer, Tsuga) in partly shaded deciduous forests from 760 to 1500 m elevation.

Distribution. East Asia and eastern North America; in North Carolina found in the upper Piedmont and Blue Ridge ecoregions.

Literature

Brodo, I.M. (1991) Studies in the lichen genus Ochrolechia. 2. Corticolous species of North America. Canadian Journal of Botany 69: 733-772.

Brodo, I.M., S. Duran Sharnoff & S. Sharnoff. (2001) Lichens of North America. Yale University Press, New Haven & London. 795 pp.

Vainio, E.A. (1918) Lichenes ab A. Yasuda in Japonia collecti. Botanical Magazine Tokyo 32: 154-163 (original description).