Flora of New Zealand Series

Holotype: New Zealand. Sine loco [probably Wellington], Charles Knight ex Herb. Leighton – BM.

Description : Thallus orbicular to spreading, 3–12(–20) cm diam., closely attached from centre to margins, or with margins ±free, corticolous. Lobes short and rounded to linear-elongate, 5–8(–12) mm wide, 5–15(–25) mm long, ragged, deeply incised, complex-imbricate marginally and centrally or with larger apical lobes, ±discrete. Margins rarely rounded, to ragged-incised or crenate, ± sinuous and slightly ascending, moderately to densely isidiate–phyllidiate. Upper surface undulate or plane, occasionally shallowly wrinkled or ridged, occasionally dimpled-papillate (internal cephalodia), glaucous-green when moist, pale grey-green to fawnish often suffused red-brown when dry, matt or glossy, without maculae or soredia; isidiate–phyllidiate and pseudocyphellate. Phyllidia mainly marginal and also spreading onto lamina, and in central parts thallus may be totally obscured by a dense crust of phyllidia; phyllidia flattened, to 0.1 mm wide and to 1 mm tall, subdichotomously to complexly branched, subterete in parts, apices often inflated. Isidia marginal and laminal, terete, minute at first, to 0.1 mm tall and 0.02–0.05 mm wide, then expanded-glomerulate and branching, becoming loosely to densely coralloid, fragile, easily broken from lamina and leaving pits, also associated with margins of pseudocyphellae, more common in older parts, at length becoming flattened-phyllidiate. Pseudocyphellae sparse to frequent, scattered, minute, white, punctiform near margins, to 0.2 mm diam, rounded or occasionally linear centrally, often surrounded by groups of minute, globular, fragile isidia. Medulla white. Photobiont green. Lower surface whitish to pale-fawn or yellowish, slightly darker centrally, often glabrous, glossy, wrinkled in a narrow, marginal zone, elsewhere evenly and thickly tomentose, tomentum pale-fawn to dark red-brown, close and velvety, to shaggy-arachnoid. Pseudocyphellae very rare, best seen at or near margins, white, flat, fleck-like, to 0.1 mm diam. Apothecia rare, scattered, solitary, laminal or submarginal, sessile, constricted at base, 0.5–2.5 mm diam., rounded to subirregular, shallowly concave to plane or ±undulate, disc pale red-brown, margins persistent, minutely crenate-scabrid, pale pinkish, matt, epruinose, not phyllidiate or isidiate, obscuring disc when young. Ascospores brown, 1–3-septate, ellipsoidal, apices rounded or pointed, contents vacuolate, 27–34 × 7–9 μm.

Chemistry : 7β-acetoxyhopan-22-ol, hopane-7β, 22-diol (tr.), hopane-15α,22-diol.

N: Northland (Three Kings Is, Matai Bay Karikari Peninsula, Bay of Islands, Poor Knights Is, Hen & Chickens Is, Little Barrier I., Great Barrier I., Waiwera Scenic Reserve), Wellington (Manawatu, Wellington). S: Nelson (N of Westport), Westland (Greymouth), Otago (Mt Watkin, Maungatua, Taieri Mouth) [map in Galloway (1988a: 244, fig. 124)]. An epiphyte of trees and shrubs, rarely on soil. Most commonly collected from northern, coastal forest, s.l. to 510 m.

Endemic

Illustration : Galloway (1988a: 242, fig. 123).

Pseudocyphellaria wilkinsii is characterised by: short, rounded to linear-elongate, rather ragged, fragile lobes with incised, isidiate–phyllidiate margins; a white medulla; a green photobiont; white pseudocyphellae on both upper and lower surfaces; terete to coralloid isidia on lamina and associated with laminal pseudocyphellae; and a two-hopane chemistry.