Flora of New Zealand Series

Thallus heteromerous, foliose, lobate, dorsiventral, lobes 0.5-5(-8) cm diam. Upper surface corticate, cortex paraplectenchymatous, smooth or ± wrinkled or plicate, glabrous, matt or shining or ± scabrid or tomentose or pruinose, bluish-, brownish or yellowish-green or reddish-brown, terricolous or muscicolous or corticolous. Medulla white, loosely interwoven. Photobiont blue-green, Nostoc, or green, Protococcus. Lower surface decorticate, arachnoid, ± whitish or brownish, ± distinctly veined. Veins flat or raised, rhizinate. Rhizines short or long, pale or dark, simple to fasciculate, often with an anchoring squarrose tuft. Apothecia round or irregular, marginal, horizontal or on vertical, ascending lobules, often with margins reflexed, exciple areolate-tomentose, or ± lacking, disc red-brown to brown-black, epruinose, margins flesh-coloured to pale brownish, often ± verrucose. Epithecium red-brown. Hymenium colourless to pale brownish. Hypothecium colourless to brown. Asci clavate-cylindrical, 8-spored with a well-defined apical ring structure. Ascospores fusiform or acicular, 3-9-septate, colourless or brown.

Peltigera is a genus of c. 30 species of wide distribution found in temperate zones of both Northern and Southern Hemispheres and at high altitudes in the tropics. Although usually growing on damp soil, logs or moss, specimens occur in exposed alpine habitats on soil or among rocks in fellfield where humidities are not too low. The most recent account of the New Zealand species is that of Murray [ T.R.S.N.Z. 88: 388-398 (1960)], but his treatment is now much in need of revision. Useful information is given in the most recent account of European species [Vitikainen in Poelt and Vězda, Bestimmungsschl. eur. Flecht. Erg. 2: 236-242 (1981)]. Chemically Peltigera is closely related to Nephroma with the same series of terpenes being found in both genera. The depside gyrophoric acid also occurs in Peltigera. Seven species are recognised in New Zealand in this account although all taxa are not well defined and a future revision (an urgent necessity) will undoubtedly present a somewhat larger assemblage of species. The genus is still poorly collected in alpine, and North I., habitats.