Flora of New Zealand Series

Holotype: New Zealand. Nelson, Maruia River, Speargrass Flat near Springs Junction. On twigs of wayside shrubs, 22 September, 1981. D.J. Galloway, CHR 381022! Isotype in BM.

Thallus irregularly spreading, (2-)5-15 cm diam., loosely attached, corticolous. Lobes ± linear-elongate, subcanaliculate to plane, subdichotomously to irregularly or complexly branched, 1-10 mm wide and 0.5-5 cm long, margins entire, slightly thickened, occasionally ± ascending, rarely subdenticulate with raised, yellow pseudocyphellae. Upper surface shallowly to deeply faveolate, interconnecting ridges smoothly rounded or sharp, dark grey-blue when wet and conspicuously white-maculate in well-defined patterns (×10 lens), pale greyish or greenish-grey to greyish-buff when dry, sometimes suffused reddish- brown in parts, matt or slightly shining, often irregularly cracked, minutely scabrid-areolate in parts. Medulla white. Photobiont blue-green. Lower surface pale whitish-buff, distinctly wrinkled-bullate, ± evenly tomentose to margins, tomentum thin, silky, short, white or buff, thicker and darker (becoming brown) centrally. Pseudocyphellae minute, bright yellow, round, 0.05-0.3 mm diam., scattered, slightly raised above tomentum, decorticate area plane, margins not prominent. Apothecia marginal or submarginal, subpedicellate, 0.5-3.5 mm diam., plane to shallowly convex-undulate, disc in young stages obscured by margins, at maturity dark red-brown to black, matt, epruinose, margins denticulate, pale buff or flesh-coloured, often obscured by disc, exciple corrugate-scabrid, buff or pale flesh-coloured. Ascospores biseriate, brown, mainly polaribilocular, occasionally 3-septate, 20-30.6 × 8.3-10.2 µm. Pycnidia occasional to frequent, scattered, black, punctiform, minute. Chemistry: Calycin, pulvinic dilactone, pulvinic acid, tenuiorin, methyl lecanorate, gyrophoric acid (tr.), hopane-6α,22- diol, salazinic and consalazinic acids and an unidentified terpene.

S: Nelson (shores of Lake Rotoiti, Maruia River near Springs Junction), Canterbury (Boyle River). Still rather rarely collected, on bark of Leptospermum and twigs of Nothofagus solandri var. cliffortioides.

Endemic

P. maculata is distinguished from P. lechleri by the ± flat lobes which are never canaliculate- ascending and rarely dark chestnut-brown at the apices, by the smooth faveolae and shallow interconnecting ridges, the thin tomentum of the lower surface and the distinctly thickened lower margins to the lobes. It is also corticolous and never terricolous as is P. lechleri. It is separated from P. crassa by the pale, thinly tomentose, bullate lower surface, from P. crocata by the absence of soredia and from P. neglecta by the absence of marginal phyllidia.