Hypotrachyna livida (Taylor) Hale

Hypotrachyna livida

Parmelia livida Taylor, 1847:171. [Type collection: New Orleans, Louisiana, Hooker Herbarium (FH-TAYL, lectotype; BM, H, isolectotypes).]

Parmelia osseoalbida Lynge, 1914:133. [Type collection: Porto Alegre, Rio Grande do Sul, Brazil, Malme 595 (S, lectotype; UC, UPS, isolectotypes).]

Thallus closely adnate, rather coriaceous (on bark) to fragile (on rock), whitish mineral gray, 4–9 cm broad; lobes sublinear, dichotomously branched, contiguous, 1–2 mm wide; upper surface shiny, plane to rugulose, lacking soredia and isidia; lower surface moderately rhizinate, the rhizines sparsely dichotomously branched. Apothecia numerous, adnate to substipitate, 1–5 mm in diameter; spores 5μ × 10μ–12μ.

CHEMISTRY.—Cortex K+ yellow, medulla K−, C−, KC+ rose, P− (atranorin, colensoinic acid, norcolensoinic acid, 4-O-demethylphysodic acid, physodic acid, lividic acid, and associated unknowns).

DISTRIBUTION.—Southeastern United States, Bahamas, Venezuela, southeastern Brazil southward to Argentina).

HABITAT.—On tree trunks and branches or (more rarely) on rocks, in open forests and gallery forests at 500–2800 m elevation (to near sea level in the United States).