Hypotrachyna subaffinis (Zahlbr.) Hale

Hypotrachyna subaffinis

Parmelia subaffinis Zahlbruckner, 1929:213. [Type collection: Based on P. affinis Vainio, not P. affinis (Dickson) Acharius, 1803:212 (= Pannaria).]

Parmelia affinis Vainio, 1890:52. [Type collection: Carassa, Minas Gerais, Brazil, Vainio 1331 (TUR, Vainio herbarium number 3010, lectotype; BM, isolectotype).]

Thallus closely adnate on bark, sea-foam yellow, 3–5 cm broad; lobes sublinear, dichotomously branched, 0.4–2 mm wide; upper surface plane, continuous, sorediate, the soralia capitate, mostly laminal; lower surface densely rhizinate, the rhizines often projecting along the margins. Apothecia rare, adnate, 0.7–2.5 mm in diameter; spores 5μ–7μ × 8μ–11μ.

CHEMISTRY.—Cortex K+ yellowish, medulla K−, C−, P+ pale orange (usnic acid, echinocarpic acid, and associated unknowns).

DISTRIBUTION.—Mexico, Central America, West Indies, Brazil.

HABITAT.—On trees (oaks and pines) in open forests at 1000–2000 m elevation.