Flora of New Zealand Series

≡Lecidea disciformis var. albula (Nyl.) Linds., Trans. Linn. Soc. 25 (3): 548 (1866).

≡Lecidea albula Nyl., Bull. Soc. linn. Normandie sér. 2, 2: 517 (1868).

=Buellia rorida Hellb., Bihang K. Sv. Vet.-Akad. Handl. 21(3/13): 116 (1896).

Holotype: New Zealand. Sine loco (? Castlepoint), W. Colenso 5021 – H-NYL 9318 [fide Triebel (1987: 344)]. Isotypes – BM, WELT.

Buellia rorida. Lectotype: New Zealand. Napier, on limestone, viii.1874, S. Berggren 166 B2 – S [fide Galloway (1985a: 52)].

Description : Flora (1985: 51–52 – as Buellia rorida).

N: Hawke's Bay (Napier). S: Nelson (Kaihoka Lakes), Marlborough (S of Waipapa Bay, Kaikoura, Goose Bay), Canterbury (Nape Nape, Weka Pass, Castle Hill, Flock Hill, Mt Somers), Otago (Ngapara, Karitane), Southland (Castle Rock, Clifden). Widespread on limestone, coastal and inland.

Australasian

Buellia albula is characterised by: the saxicolous habit (basicolous rocks); the thickish white, tartareous, spreading thallus; subimmersed, lecideine apothecia with a prominent black margin and grey-white pruinose discs; a yellow-brown to dark-brown epithecium, 10–12.5 μm thick; a hyaline hymenium, 40–50 μm tall; a yellow-brown to brown hypothecium; and oval to broadly ellipsoidal ascospores, 12–15 × 5–9 μm. Zahlbruckner (1931: 334) placed the taxon Lecidea whakatipae C.Knight in synonymy with B. albula, but as pointed out by Triebel (1987: 343) this latter species is lichenicolous and is referable to * B. badia (= * Monerolechia badia q.v.) and has nothing whatever to do with B. albula.