Flora of New Zealand Series

≡Lichen candelarius L., Sp. Pl. 2: 1141 (1753).

Description : Thallus of irregular hummocks or cushions 0.5–2(–6) cm diam., often coalescing into extensive swards. Lobes 0.5–1(–2.5) mm wide, 1–2 mm tall and to 0.1 mm thick, crowded, congested, cochleate or decumbent at first (initially developing from soredia), soon curving upwards and becoming ±vertical, laterally compressed, ±flabellate, margins irregularly crenate or pectinate or ragged, sorediate; soredia granular, yellow-green. Upper or dorsal surface smooth or minutely wrinkled, matt, mustard-yellow to yellow-green (green in shade). Lower or ventral surface whitish below, roughened-arachnoid, green or yellow-green towards margins and ±densely granular sorediate. Apothecia and pycnidia not seen.

Chemistry : Parietin (major), erythroglaucin, xanthorin, fallacinal, fallacinol, emodin, and parietinic acid (minor) (Arnold & Poelt 1995).

N: Northland (Hihitahi State Forest). S: Canterbury (Christchurch), Otago (Mt Benger, Teviot Valley, Dunedin, East Taieri, Akatore, Milton), Southland (Forest Hill, Awarua). Mainly an epiphyte of introduced trees in urban parks and street plantings where it appears able to withstand moderate to high pollution levels. It associates with the following lichens: Amandinea punctata, Candelariella reflexa, Desmococcus sp., Parmelina labrosa, Physcia adscendens, Ramalina celastri and Xanthoria polycarpa, and is known from the following phorophytes: Betula pendula, Cupressus macrocarpa, Laburnum anagyroides, Pinus radiata, Populus nigra, Quercus robur, and Ulmus ×hollandica, where it can often form prominent colonies and swards on lower trunks and basal plates. Outside of these urban and/or industrial habitats, the species is known from decorticated wood bordering an estuary, and from a shaded underhang on a schist tor at 1125 m in Central Otago. It appears probable that the species is introduced in New Zealand. Known also from Great Britain, Europe, Scandinavia, Svalbard, North and South America, Asia, Bouvetøya, South Georgia, South Sandwich Is, South Orkney Is, South Shetland Is, and Antarctica (Poelt & Petuschnig 1992b; Purvis et al. 1992; Nimis 1993; Santesson 1993; Esslinger & Egan 1995; Elvebakk & Hertel 1997; Galloway & Quilhot 1999; Scholz 2000; Brodo et al. 2001; Øvstedal & Lewis Smith 2001; Lindblom 2004; Santesson et al. 2004; Søchting et al. 2004; Elvebakk & Bjerke 2006).

Bipolar

Illustrations : Moberg & Holmåsen (1982: 190); Thomson (1984: 483); Redón (1985: fig. 90); Wirth (1987: 503; 1995b: 973); Goward et al. (1994b: 139, fig. 10B); McCune & Geiser (1997: 318); St. Clair (1999: 220); Dobson (2000: 412); Brodo et al. (2001: 743, pl. 915).

Xanthoria candelaria is characterised by: the corticolous/lignicolous habit; the crowded, ascending, laterally compressed lobes with erose-sorediate rather ragged margins, a smooth yellowish or yellow-green dorsal surface and an eroding, roughened, green-white or yellow-green, sorediate ventral surface. Xanthoria candelaria varies mainly in the degree of development of soredia, in the colour of the thallus (shaded specimens are green or grey-green with little or no development of parietin), and in the size of the lobes, but further work is needed to ascertain the limits of variation in New Zealand populations and whether in fact the New Zealand populations are indeed conspecific with material from the Northern Hemisphere. Kondratyuk et al. (2001: 356) give a useful table of characters separating X. candelaria from closely related taxa.