Usnea rubicunda
Description : Flora (1985: 601–602).
Chemistry : Medulla K+ yellow→orange or red; containing usnic, salazinic and norstictic acids.
N: Northland (Three Kings Is, Herekino Gorge, Kawerua, Cavalli Is, Bay of Islands, Tutamoe, Heni I., Great Barrier I., Whangarei, Waiheke I., Glorit) Auckland (Auckland City, Rangitoto I.), South Auckland (Coromandel Peninsula, Whitianga, Great Mercury I., Slipper I., Shoe I., Te Aroha, Kaimai Ra., Rotorua, Paremoremo, Hamilton, Pio Pio), Wellington (Erua, Totara Reserve, Levin, Kapiti I., Rimutaka Ra.). S: Nelson (Kaihoka Lakes, Lake Rotoroa, Inangahua Junction), Marlborough (d'Urville I., Chetwode Is), Westland (Greymouth, Fox Glacier), Canterbury (Boyle River, Arthur's Pass, Riccarton Bush, Waihi Gorge), Otago (Flagstaff, Mt Charles, Saddle Hill, Taieri Mouth, Akatore), Southland (Forest Hill, Thomson's Bush Invercargill). Throughout, on trees (both native and introduced), decorticated wood (gates, fenceposts, power poles, wooden buildings etc.) and rocks, lowland and coastal. Very common and polymorphic. Known also from Great Britain, Europe, Asia, North and South America, East Africa, the Pacific, and Australia (Swinscow 1979a; Purvis et al. 1992; Nimis 1993; Esslinger & Egan 1995; Halonen et al. 1998; Stevens 1999, 2004b; Scholz 2000; Brodo et al. 2001; Llimona & Hladun 2001; Aptroot 2002e; Coppins 2002b; Wolseley et al. 2002; McCarthy 2003c, 2006).
Cosmopolitan
Illustrations : Swinscow & Krog (1979: 241, fig. 14); Phillips (1987: 187 – as Usnea rubiginea); Kantvilas & Jarman (1999: 153); Dobson (2000: 390, fig. 2, 398; 2005: 447); Brodo et al. (2001: 723, pl. 891).
Usnea rubicunda is characterised by: the corticolous (rarely saxicolous) habit; the reddish colour of the cortex (varying from pale-rose to dark reddish brown), pale at base; spinules and fibrils that give a somewhat "bristling" appearance to the thallus; and salazinic and norstictic acids in the medulla. It is discussed in Wright (2004).
