Flora of New Zealand Series

≡Parmelia arnoldii Du Rietz, Nytt Mag. Naturvid. 62: 80 (1924).

Description : Flora (1985: 356).

Chemistry : Cortex K+ yellow; medulla K−, C−, KC+ pink, Pd−, UV±bluish-white; containing atranorin, alectoronic and α-collatolic acids.

N: Wellington (Pohangina Valley, Pongaroa). S: Southland (Tiwai Point). On tree trunks, still very poorly collected in New Zealand. Known also from Europe, North and Central America and the Caribbean, Chile, and Gough I. in the South Atlantic Ocean (Hale 1965b; Galloway & Quilhot 1999; Elix & Gremmen 2002; Nash & Elix 2002g; Nimis & Martellos 2003).

Pantropical

Illustrations : Goward et al. (1994b: 96, fig. 4A); McCune & Gieser (1997: 195); Brodo et al. (2001: 492, pl. 572).

Parmotrema arnoldii is characterised by: the corticolous habit; the loosely adnate thallus, the rather narrow lobes with ciliate margins and numerous dentate laciniae; soralia on marginal laciniae; and alectoronic and α-collatolic acids (UV+ blue-white) in the medulla.