Flora of New Zealand Series

Holotype: New Zealand. Nelson, Owen Ra., schist soil, 1130 m, 16.xii.1982, J.K. Bartlett 28249 – AK. Isotype – BG.

Description : Thallus squamulose–crustose, forming ±circular cushions on a thick, well-developed blackish prothallus, the central area being small-squamulose–areolate with radiating, enlarged peripheral squamules, to 200 μm thick with conspicuous (to 50 μm thick) cortex of thick-walled cells. Upper surface smooth, waxy, reddish-brown. Apothecia common in central parts, to 1 mm diam., disc black, eventually convex with distinct proper margin. Hymenium 70–80 μm tall, pigmented blackish in upper parts, I+ deep blue. Asci clavate, 50–60 × 10–12 μm with a distinct, amyloid apical ring-structure. Ascospores narrow-ellipsoidal, 13–16 × 4– 5 μm. Pycnidia not seen.

Chemistry : TLC−, all reactions negative.

S: Nelson (Upper Cobb Valley, headwaters of Burgoo Stream; Owen Ra.), Canterbury (Upper Godley Valley). C: On alpine rocks and soil, where it occurs with Pannaria hookeri and Steinera neozelandica. Still very poorly known and collected. First collected by David Scott 240 (OTA 049273), 25.viii.1958, from soil among S-facing rock bluffs at 1000 m.

Endemic

Illustration : Jørgensen (1999: 266, fig. 6A, B).

Parmeliella crassa is an unusual species, easily recognised by its thick, waxy squamules developed on a thick prothallus and broad-margined apothecia. It is related to P. nigrocincta, which is mainly a lowland corticolous species. In extreme habitats the species becomes blackened, but is still easily recognised because of its special characters.