Buellia otagensis Zahlbr.
Lectotype: New Zealand. Otago, Otago Heads on rocks. J.S. Thomson ZA31 (T1013), CHR 374334!
Thallus smooth, coriaceous, shining in parts or matt, 0.1 mm thick, slightly roughened, pale whitish or brownish-grey, matt, ± continuous and irregularly cracked, not areolate, without a distinct prothallus, in broad patches 4-8 cm diam., saxicolous. Apothecia crowded or scattered, sessile to ± innate, black, matt, epruinose, rounded, constricted at base, 0.1-0.6 mm diam., flat, margin entire persistent, concolorous with disc. Epithecium brown-black, 30 µm tall. Hymenium colourless 100-110 µm thick. Hypothecium thick, brownish. Paraphyses dense, straight, simple, not septate, apices globose. Ascospores ± biseriate, broadly ellipsoid or broadly oval, thick walled, locules ± equal, oval or rounded, 9.6-16 × 7.5-9 µm, septum 3 µm thick.
S: Otago Harbour.
Endemic
Associated on littoral rocks with species of Caloplaca.
