Flora of New Zealand Series

≡Opegrapha dispersa Schrad., Annln Bot. 22: 86 (1797).

Description : Flora (1985: 11).

N: Known from only two NZ collections to date. Sine loco, W. Colenso 5143 (BM). Wellington, J. Buchanan (BM). Probably more widely distributed on twigs and bark of smooth-barked trees and shrubs. It is a pioneer species on young twigs and trunks of deciduous trees, known from temperate parts of Europe, Scandinavia and North America (Sundin & Tehler 1998; Nimis & Martellos 2003) but is absent from the British Isles (Coppins 2002b) and the Mediterranean.

Cosmopolitan

Illustrations : Galløe (1972: p. 47, pls 34, 169); Wirth (1995: 137); Boqueras (2000: 74, fig. 7D).

Arthonia dispersa is characterised by: the corticolous habit; the pale, grey-brown, glossy thallus; frequent, slender, dark red-brown to brown, elongate lirellate apothecia, often in parallel lines to stellate and irregular; and oblong-ovate, 1-septate ascospores, 10–13 × 3–4 μm.