Flora of New Zealand Series

=Lecidea dunedina Zahlbr. pr.p., Denkschr. Akad. Wiss. Wien math.-naturwiss. Kl. 104: 301 (1941). [Material from Abbott's Hill cited in the protologue above is referable to L. plana. Material from Kyeburn also cited in the protologue under this name is referable to L. lapicida].

Lecidea dunedina. Lectotype: New Zealand, Otago, Abbott's Hill, Dunedin, viii.1933, J.S. Thomson T 942 [Z133] – W [fide Hertel (1984b: 421)]. Isolectotype – CHR 347043, OTA. [The two localities cited by Zahlbruckner (1941: 302) for Lecidea dunedina comprise two different species: the Abbott's Hill material which Hertel has chosen as lectotype, is of Lecidea plana, while the Kyeburn material (J.S. Thomson T 2330 [A43], CHR 347042) is referable to Lecidea lapicida (q.v.).]

Description : Thallus verrucose to dispersed, cryptothalline, of scattered areolae, in patches to 12 cm diam., up to 0.5 mm thick. Upper surface areolate, areolae irregular to angular, pale grey, plane, roughened, 0.5–1 mm diam. Medulla I ±pale-violet. Apothecia round to auriculate, scattered to crowded, sessile, constricted at base, 1–1.6 mm diam., disc plane, black matt, sometimes slightly pruinose, margins persistent, black, matt. Hypothecium colourless, subhymenial layers colourless. Hymenium 55–65 μm tall, colourless, I+ blue; epithecium dark-green, 10–13 μm thick. Asci 40–50 × 9–12 μm, tholus 5–9 μm thick. Ascospores ellipsoidal, 9–12.5 × 3–4 μm. Pycnidia immersed. Conidia 10–12 × 1 μm.

Chemistry : Thallus K−, C−, KC−. Pd−; containing planaic acid (major), 4- O -demethylplanaic acid (tr.) (Culberson & Hertel 1979).

S: Canterbury (Craigieburn Ra.), Otago (Hyde Rock, Old Man Ra., Abbott's Hill, Dunedin). On subalpine to alpine rocks, but apparently a rather rare lichen in New Zealand (Hertel 2001). Known also from Europe, Scandinavia, Japan, North America, Colombia and Australia (Hertel 1975b, 1977a, 1995, 2001; Culberson & Hertel 1979; Rambold 1989; Hertel & Andreev 2003).

Cosmopolitan

Illustrations : Wirth (1995a: 507).

Lecidea plana is characterised by: the saxicolous habit; the non-amyloid medulla; a colourless hypothecium; a greenish epithecium; and by the characteristic chemistry. It is similar to grey forms of L. lapicida.