Flora of New Zealand Series

≡Agyrophora zahlbruckneri (Frey) Llano, Monogr. Lich. Fam. Umbilicariaceae: 60 (1950).

Holotype: New Zealand. Canterbury, head of Yake [Lake] Tekapo, on flat top of rock by stream, 800 m, ["Top Hut"], i.1935, H.H. Allan R21 [ZA 3260] – G. Isotype – CHR 160027.

Description : Thallus orbicular, rather small and compact, 1–3(–4) cm diam., monophyllous to weakly polyphyllous; lobes rounded, margins sinuous-complicate, notched, incised or laciniate, rarely entire, often with projecting flattened rhizinomorphs. Upper surface coriaceous, smooth to shallowly wrinkled, more strongly wrinkled above umbilicus, occasionally with small tears or holes, pale- to dark-grey, or greyish brown, delicately white-pruinose in parts, slightly granular-crystalline on wrinkles above umbilicus, sometimes areolate around larger apothecia, areolae subconvex separated by very narrow cracks. Lower surface uniformly black from margins to centre or occasionally with brownish patches at or near margins, smooth, slightly sooty or minutely roughened (×10 lens), without wrinkles. Umbilicus compact, 1.5–2(–3) mm diam. Rhizinomorphs rather sparse, clustered at or near margins, absent centrally, greyish, grey-brown to blackened, 2–5 mm long, cylindrical to flattened, simple to 2–3-branched and entangled, occasionally with lateral, knoblike, black, thalloconidia (×10 lens). Apothecia sessile, rarely subpedicellate, rounded to slightly distorted through mutual pressure, 0.5–1 (–2) mm diam., plane to convex, solitary and scattered to crowded and 3–4-together in groups or lines; disc black, matt, epruinose, slightly roughened-papillate but without a central sterile button or fissures; margins thin, often not apparent, glossy or matt, only very slightly raised. Epithecium dark-brown, dense, 15–20 μm thick. Hymenium, colourless to pale yellow-brown, 65–90(–115) μm tall. Paraphyses simple, septate 1.5–2 μm diam., apices slightly swollen to 3–4 μm thick. Hypothecium pale to dark yellow-brown, opaque, 75–100(–150) μm thick. Asci broadly clavate 50–65(–70) × (15–)20–25(–30) μm. Ascospores broadly ellipsoidal to ovoid, 11.5–13.5(–16.5) × 7–10 μm. Pycnidia scattered towards lobe margins, widespread centrally, punctiform, black, glossy, to 160 μm diam. Conidia bacillar, 3–4 × 1 μm.

Chemistry : Not tested.

S: Nelson (St Arnaud Ra.), Westland (Hills Peak, Mt Haast, Mt Alack), Marlborough (Mt Tapae-o-uenuku, Kaikoura Ra.), Canterbury (Craigieburn Ra., Godley Glacier, Tasman Valley, Mt Wakefield, Kea Point, Sebastopol, head of Lake Tekapo, Kirkliston Ra.), Otago (Lake Ohau, East Matukituki Valley, Dart Valley, Black Peak Mt Earnslaw, Bold Peak, Lammerlaw Ra., Umbrella Mts), Southland (Homer). On exposed rocks and boulders in alpine grassland and fellfield and on moraine boulders and high-alpine summit rocks, 600–2965 m. Associating with Neuropogon ciliatus, Pseudephebe pubescens, Rhizocarpon spp., Tremolecia atrata, Umbilicaria cylindrica, U. decussata, U. durietzii, U. krascheninnikovii, U. polyphylla, U. subaprina and U. virginis. Known also from Ecuador, Chile and Argentina (Llano 1950; Galloway & Quilhot 1999).

Austral

Umbilicaria zahlbruckneri is characterised by: the saxicolous habit; the monophyllous to weakly polyphyllous thallus, 1–3 cm diam., and with rhizinomorphs projecting from the margins; the coriaceous, smooth to wrinkled upper surface, which is pale- to dark-grey or greyish brown and delicately white-pruinose in parts to granular-crystalline on wrinkles above umbilicus; a smooth, black, sooty lower surface, with rather sparse rhizinomorphs (cylindrical to flattened) close to or at margins and absent centrally; sessile, black, plane to convex apothecia without sterile fissures or gyrae.