Flora of New Zealand Series

=Lecidea trachona var. marginatula Nyl., Flora48: 339 (1865).

≡Patellaria trachona var. marginatula (Nyl.) Müll.Arg., Bull. Herb. Boissier 2, App. 1: 65 (1894).

≡Bilimbia trachona var. marginatula (Nyl.) Hellb., Bihang K. Sv. Vet.-Akad. Handl. 21(3/13): 102 (1896).

Holotype: New Zealand. Northland, Hen I., on shaded rock in forest, L.B. Moore ZA 18 – W. ? Isotype – CHR.

Lecidea trachona var. marginatula. Holotype: New Zealand. Otago, Green Island Bluff [Black Head], on columnar basalt, October 1861, W.L. Lindsay – H-NYL 18958. Isotype – E [erroneously designated as lectotype (Galloway (1985a: 35)].

Description : Flora (1985: 35).

N: Northland (Hen & Chickens Is). S: Otago. Lowland, coastal, on rock.

Endemic

Bacidia tholera is characterised by: the saxicolous habit; the greyish, greyish yellow to olivaceous, areolate thallus; sessile, glossy, black or brownish apothecia; a pale purplish grey hymenium; a dark purplish hypothecium (K+ purple-violet); and oblong-fusiform, 3-septate ascospores, 14–18 × 4–6 μm.