Flora of New Zealand Series

Lecanora subgelida Nyl., C. r. hebd. Séanc. Acad. Sci. Paris 83: 89 (1876).

Holotype: New Zealand. Campbell Is. M. Filhol, 1874, H-NYL.

Thallus determinate, suborbicular, forming effigurate patches, to 4 cm diam., saxicolous. Marginal lobes broad, plane, smooth, 1.5-5 mm long, 1-2.5 mm broad, contiguous, separated by cracks, 0.1-0.3 mm wide, subcuneate, irregularly branched, apices rounded or subcrenulate and produced inwards towards centre. Upper surface smooth, irregularly cracked, not areolate, creamish, matt, white-pruinose, without isidia or soredia. Cephalodia scattered, sessile, suborbicular to irregular, flattened, 2-7 mm diam., effigurate, with radiating folds and cracks, dark pinkish or pale brownish, matt. Apothecia irregularly scattered, rounded, to 2 mm diam., subpedicellate, thalline margin thick, entire, rounded, white-pruinose, disc plane or subconcave, red-brown or reddish, matt, slightly pruinose. Hymenium 285-320 µm tall, epithecium with sordid yellow crystals. Hypothecium colourless. Paraphyses not thickened at apices. Ascospores uniseriate, ellipsoid to broadly ellipsoid 25-30 × 12-21 µm. Pycnidia immersed, ostioles minute, black, punctiform. Conidia not seen. Chemistry: Cortex K-, C+ rose; medulla K- or pale yellow, C+ rose, Pd-.

C: Mt Azimuth.

Endemic

P. subgelida appears to be restricted to the Subantarctic Islands of New Zealand. It has the largest spores and highest hymenium of any species in Placopsis.