Hypotrachyna osteoleuca (Nyl.) Hale

Hypotrachyna osteoleuca

Parmelia osteoleuca Nylander, 1863:439. [Type collection:Bogota, Colombia, Lindig 2528 (H, lectotype; BM, FH, G, H, M, P, W, isolectotypes).]

Thallus closely adnate or becoming loosely attached as thick thallus mats form, ashy white or darkening, 5–10 cm broad; lobes sublinear, often imbricate and crowded, 1–3 mm wide; upper surface plane, smooth, continuous, lacking soredia and isidia but usually heavily pycnidiate; medulla white to pale salmon; lower surface sparsely to densely rhizinate, the rhizines densely dichotomously branched. Apothecia common, adnate to substipitate, the disc dark brown, 1–4 mm in diameter; spores 5μ–6μ × 7μ–9μ.

CHEMISTRY.—Cortex K−, medulla K−, C+ red, P− (lichexanthone, olivetoric acid, rhodophyscin (in lower medulla), and unidentified substances).

DISRTIBUTION.—Colombia and Venezuela.

HABITAT.—On exposed rocks in the paramo at 2300–3000 m elevation.