Type locality: USA, California, Farallon Islands, J. Lindahl, 1886 (N-NYL 30523 - holotype).

Type locality coordinates: 37°44'N, 123°4'W.

ITS barcode: Data lacking.

Description: Lichen. Thallus fruticose, ("dwarf-fruticose"), 6-12 mm high; forming dense cushions, commonly 15-25 mm broad; apical portions orange, basal portions tan to white, occasionally blackening. Primary branches erect or decumbent, to 1.1 mm wide, dorsiventrally compressed; lower surface paler than above. Sedondary branches short, flabellate; tips irregularly dichotomous. Rhizines lacking. Tissues more or less radially arranged. Cortex 24-88 µm thick, prosoplectenchymatous; dorsal portion of highly irregular thickness due to intrusion of algal layer, ventral portion more regular. Algal layer continuous but dorsiventrally differentiated; dorsal portion 47-84 µm thick, ventral portion 24-55 µm thick. Alpal cells trebouxioid, 9-14 µm in diameter. Medulla hyaline; peripheral portion lax, central portion with one or more cartilaginous strands. Apothecia terminal on branches, commonly eccentrically attached, 1.5-3.0 mm broad; becoming strongly concave; margin thick, persistent, becoming flexuous and often strongly sinuate; orange. Epithecium orange-granular; hymenium 48-68 µm high; hypothecium hyaline to yellowish, becoming prosplectenchymatous, 36-62 µm thick, algal layer below. Paraphyses filiform, approximately 2 µm in diameter, tips often clavate, unbranched, occasional anastomoses. Asci clavate, 34-45 / 10-15 µm. Spores hyaline, elliptical; simple (not polarilocular), commonly with an incomplete transverse cytoplasmic band; 9.5-14.5 / 4.6-6.0 µm; 8 per ascus. Pycnidia along dorsal surface of branches, immersed, subglobose. Pycnidiospores filiform, straight or curved, 17-22 / 0.9-1.1 µm (Jordan 1980: 64).

Photobiont: Trebouxia.

Chemistry: Cortex K- blood-red, C-, KC-, P-, hymenium I+ blue, parietin (Jordan 1980: 66).

Ecology: On vertical faces of maritime silicious rocks.

Distribution type: Endemic in the Farallon Islands, California.

Taxonomy: Data lacking.

Note:

Distribution Database: Distributions

Distribution Database: Discover Life

Picture Database: Tropical Lichens

Molecular Database: Genbank

Synonym Database: Index Fungorum

Synonym Database: Mycobank