Usnea rubrotincta
=Usnea spilota Stirt., Scott. Nat. 6: 294 (1882).
≡Usnea rubicunda var. spilota (Stirt.) G.N.Stevens, Biblthca Lichenol. 72: 90 (1999).
Description : Thallus erect to subpendent, to 35 cm tall, red to reddish brown or greenish grey with a few flecks of red when moist, reddish brown to straw-yellow with flecks of red on storage, pale- to dark-brown at base, branching anisotomic-dichotomous. Branches terete, 0.5–1.5 mm diam., uninflated tapering towards apices, with many lateral branchlets and fibrils, cortex matt, without pseudocyphellae and maculae. Papillae cylindrical. Soralia common, mainly on lateral branches and fibrils, discrete, punctiform to sinuous, plane to raised, soredia granular. Medulla dense, 13–25% of radius, hyaline; axis solid, 20–50% width of branch. Apothecia not seen.
Chemistry : Medulla K+ yellow→orange or red; containing usnic, salazinic and norstictic acids with traces of galbinic, connorstictic, consalazinic and protocetraric acids.
S: Marlborough (d'Urville I.). On rocks and soil. Known also from Asia, Europe, Japan, Taiwan, Africa, South America (Peru) and Australia (Stevens 1999, 2004b; Ohmura 2001; McCarthy 2003c, 2006).
Cosmopolitan
Usnea rubrotincta is characterised by: the saxicolous/corticolous habit. It is closely similar to U. rubicunda (q.v.), but is distinguished from it by the sinuous soralia forming on scars of detached fibrils and lateral branchlets.
