Arthrorhaphis alpina
≡Lecidea flavovirescens var. alpina Schaer., Lich. Helv. Spicil.: 162 (1833).
Description : Thallus squamulose-lobulate, irregularly spreading, 0.5–3(–5) cm diam., muscicolous-terricolous. Squamules 0.2–5 mm diam., round to irregular, convex, swollen, scattered, discrete to ±crowded-congested, plicate, ±cerebriform or areolate-imbricate, often hollow in apical parts, vivid yellow-green, yellow to sordid yellow-brown or ±blackened in parts, surface matt, somewhat roughened, minutely crazed with fine black lines (×10 lens), soredia generally absent, present in some specimens from sheltered habitats. Apothecia moderately common, sessile, 0.5–3 mm diam., solitary to 5–6-conglomerate, developed at margins of squamules, or sometimes in discrete, scattered clumps independent of thalline squamules, round to somewhat irregular, at first slightly immersed between squamules, soon becoming convex and at maturity ±convex-convolute and projecting above squamules, marginate at first, then immarginate, disc black, matt, epruinose, slightly roughened, plane at first, soon convex and at maturity markedly rugose-plicate. Epithecium densely granular, greenish black, pigment dissolving in K, 25–35 μm thick. Hymenium 124–145 μm tall, opaque, appearing finely granular, pale straw-coloured to grey-brown. Asci narrowly clavate, tapering at foot, 90–145 × 9.11.5 μm. Ascospores colourless, 7–12(–14)-septate, acicular, apices tapering, pointed (55–)60–75(–85) × 2.5–4 μm.
Chemistry : Rhizocarpic acid, epanorin and unidentified pigments (Obermayer 1994).
N: Wellington (Mt Ruapehu). S: Nelson (Mt Arthur, St Arnaud Ra., Wairau Valley), Canterbury (Mt Sebastopol), Otago (N Huxley Valley, Mt Cargill). C: (Mt Honey, Mt Lyall). On soil in alpine fellfield. Widely distributed in the Northern Hemisphere where it is a circumpolar, arctic-alpine species (Obermayer 1994; Hansen & Obermayer 1999; Nimis & Martellos 2003). It has a rather restricted occurrence in the Southern Hemisphere being known from alpine regions of New South Wales in Australia (Filson 1996), from Tasmania (Kantvilas 1996b), Mt Wilhelm in Papua New Guinea in summit tundra at 4900 m, from Hawai'i (Galloway & Bartlett 1986) and from the E coast of the Antarctic Peninsula (Øvstedal & Lewis Smith 2000). Recently reported from Campbell I. (Fryday 2004a), and the South Shetland Is (Søchting et al. 2004).
Bipolar
Illustrations : Obermayer (1994: 329, fig. 5 A–D; 330 fig. 6F, H–L); Lumbsch et al. (2001: 17).
Arthorhaphis alpina is characterised by: the compact, squamulose-lobate (often hollow at the apices) thallus which is generally free of soredia (except in some sheltered situations), by calcium oxalate crystals in the medulla, by shorter acicular ascospores than A. citrinella, the ascospores generally not lying at the same height in the ascus (Obermayer 1996).
