Flora of New Zealand Series

Holotype: New Zealand. South I., Westland, Mt Haast, col between West Peak and Middle Peak, 2955 m, 10.i.1967, [R.G.] Cunninghame (Herb B.A. Fineran 2487) – CANU.

Description : Thallus small, in dispersed to contiguous lines or patches, 3–12 mm diam., delimited at margins and between areolae by a conspicuous, thin, black, prothallus, Areolae roundish, 0.2–0.8 mm diam., to 0.15 mm thick, contiguous to scattered, straw-yellow to buff-brown, subbullate, with a shining, smooth surface (with an epinecral layer to 20 μm thick). Medulla I+ intense-violet. Apothecia solitary to crowded, in lines or in small groups, 0.4–0.8 mm diam., sessile, constricted at base; disc plane to subconvex, black, matt, epruinose, margins persistent, slightly raised above disc (to 70 μm thick), concolorous with disc, shining. Hypothecium dark-brown, 40–70 μm thick, subhymenial layer colourless, 25–40 μm thick. Hymenium colourless, 55–60(–65) μm tall; epithecium greenish, 9–13 μm thick. Ascospores broadly ellipsoidal (7–)8–9(–10.5) × (4–)4.5–5.5(–6.2) μm. Pycnidia immersed. Conidia bacillar, 7–10 × 1 μm.

Chemistry : Cortex K+ yellow→red, C−, KC+ red, Pd+ yellow-orange; containing norstictic acid.

S: Westland (Mts Haast and Haidinger), Canterbury (Mt Cook, summit rocks). On exposed high-alpine rocks 2925 –3555 m. Collected by Brian Fineran, R.G. Cunninghame, C. Livesey and H.D.Wilson. Formerly misidentified by C.W.Dodge as Lecidea durietzii H.Magn.,  L. pallidoatra Nyl., and L. triangularis H.Magn (Fineran & Dodge 1973: 277). Associating with Rhizocarpon geographicum, Sporastatia testudinea, Tremolecia atrata.

Endemic

Lecidea lapicida var. maungahukae is characterised by: the saxicolous habit (high-alpine rocks); the subbullate, buff-yellow, thalline areolae dispersed on a conspicuous black prothallus; the I+ intense-violet medulla; and norstictic acid in the medulla. Anatomically it is similar to L. lapicida var. pantherina, but the colour and morphology of the thalline areolae are different and appear to be constant and very characteristic for this high-alpine lichen (Hertel 2001).