Flora of New Zealand Series

Lecidea flavidoatra Nyl., J. Linn. Soc. Lond. Bot. 9: 257 (1866).

Lectotype: New Zealand. Otago, Fairfield, Saddlehill. October 1861. W.L. Lindsay. E!

Thallus pale greenish-white or pale yellowish-green, rimose, to ± areolate-cracked, areolae convex, smooth or minutely verrucose appearing ± subsquamulose, matt or shining, in irregular patches, 1-4 cm diam., not delimited by a marginal prothallus, corticolous. Apothecia sessile, prominent, constricted at base, 0.2-1.4 mm diam., disc black, matt, finely roughened, epruinose, concave to plane, margins thick, persistent, concolorous with disc, entire. Epithecium olive-green-black, 9-40 µm thick. Hymenium colourless, 100-160 µm tall. Hypothecium olive-black, 110-140 µm thick. Paraphyses simple, septate, not much branched, capitate at apices. Ascospores large, 8 per ascus, thick-walled especially at apices, oval, rounded or slightly pointed at apices, straight, not constricted at septum, locules equal (30-)34-40 × 15-18(-23) µm, septum 9 µm thick. Chemistry: KC+ yellow, Pd-. Usnic acid and zeorin.

N: North Auckland (Waiwera Hill Reserve). S: Nelson (Pelorus Bridge), Otago (Dunedin).

Endemic

M. flavidoatra is a characteristic species but still very poorly collected in New Zealand. It is known from Hoheria and Metrosideros bark. It is distinguished from M. marginiflexa by the warted, yellow-green thallus and the black, epruinose apothecia.