TYPE. “Ad corticem arboris prope Krausses-Lagoon (542: C. Raunkiaer) Fair Plane (F. Boergesen) in insula S. Croix (Wainio 1915). UNITED STATES. U.S. Virgin Islands, Saint. Croix.
Description. Lichenized fungus.
Thallus foliose, white to grayish green, suborbicular, 1-8 cm broad, dull, often pruinose toward the margins; lobes confluent, appressed, often appearing crustose; vegetative diaspores absent; medulla white; lower cortex black; rhizines absent. Photobiont trebouxoid alga. Ascomata lecanorine apothecia, common to abundant, 0.5-1 mm diam., sessile; disk flat, dark purple-red, red-pruinose; thalline rim thin; excipular rim indistinct. Exciple thin, poorly developed; epithecium pale to dirty red, granular, K+ yellow and dissolving pigment; hymenium hyaline, ~80 μm high; paraphyses slightly branched at apices, not capitate; hypothecium brown-black, K-. Asci clavate, 8-spored, in 2 rows; ascospores brown, 2-celled, thick-walled, 15-18 x 6-7 μm.