Flora of New Zealand Series

Holotype: New Zealand. Otago, Cromwell, on rocks at Railway station. G. Einar and Greta Du Rietz, 1927, S!

Thallus dull greenish-brown to red-brown, rather leathery, cracked into rather thick (0.2-0.5 mm) angular, areolae; areolae very irregular, centrally separated by deep cracks, rounded sublobulate at margins, ± convex, 0.5-1.2 mm diam., cortex C+ red. Apothecia very small, sunken, 2-3 per areola, 0.3-0.6 mm diam., disc red-brown, matt epruinose. Ascospores minute, ellipsoid to cylindrical, 100-200 per ascus, 3.5-5 × 1.5 µm.

S: Otago (Cromwell, Dunedin). On building stones and mortar in lowland areas, also on rocks in upland areas (Central Otago) with species of Candelariella, Rhizocarpon and Xanthoparmelia.

Endemic

A. otagensis is similar to the European species A. fuscata in habit and structure but has a pale lower, and paler upper surface, a more determinate thallus and more deeply impressed apothecia (Magnusson loc. cit. p. 279).