Flora of New Zealand Series

≡Neuropogon sphacelatus (R.Br.) D.J.Galloway, DSIR, Land Res. Sci. Rept 26: 7 (1992).

=Usnea sulphurea J.König in Olafsen & Povelsen, Reise igien. Island Appendix: 16 (1772).

≡Neuropogon sulphureus (J.König) Hellb., Bihang K. Sv. Vetensk.-Akad. Handl. 21 (3/13): 21 (1896). [For additional synonymy see Walker (1985: 92–93).]

Description : Flora (1985: 319 – as Neuropogon sulphureus).

Chemistry : Cortex K−; medulla K−, C−, KC−, Pd−; containing usnic acid.

S: Nelson (mountains above Lake Cobb, 1600 m), Otago (Mt Aspiring – NW, NE and Coxcomb ridges, Mt Avalanche, Mt Sir William, Mt Head). On rock outcrops on exposed ridges and faces, 2800–3170 m. It is genuinely rare in New Zealand being mainly restricted to a few high-alpine sites in Otago close to or E of the Main Divide. It has been recorded from the highest altitude for any species of Usnea in New Zealand. Known also from the high Arctic (Jan Mayen, Svalbard, Iceland, Greenland, Novaya Zemlya), arctic Canada, the USA (Mt Washington), Mexico, South America (Venezuela, Ecuador, Argentinian Patagonia), all at high altitudes, and from Antarctica (Walker 1985: 98–99; Esslinger & Egan 1995; Hansen 1995; Elvebakk & Hertel 1997; Convey et al. 2000; Øvstedal & Lewis Smith 2001). Thomson (1984: 286) records that skuas banded in Antarctica were recovered three months later in Greenland, and as these birds nest among colonies of Usnea sect. Neuropogon, offers this as a possible explanation for the bipolar distribution of U. sphacelata between Antarctica and Greenland.

Bipolar

Illustrations : Thomson (1984: 285 – as Neuropogon sulphureus); Walker (1985: 94, fig. 28); Hansen (1995: 71); Øvstedal & Lewis Smith (2001: pl. 96, pl. 97).

Usnea sphacelata is characterised by: the saxicolous habit; the erect, usually richly branched thallus; a subnitid to subpapillate surface with prominent bands of pigment; a lax medulla; usually lacking depsidones; a thin axis; and plane to nodular, often pigmented, soralia ±confined to secondary branches.