Flora of New Zealand Series

Thallus crustose, epiphloeodal or rarely hypophloeodal, cortex dense, often splitting and exfoliating or, less commonly, loosely organised, lacking in hypophloeodal species. Medulla well-developed to nearly hypophloeodal. Photobiont green, Trentepohlia, arranged as in Thelotrema. Apothecia emergent or rarely immersed, with a distinct thalline rim, incurved to suberect, usually forming a discrete pore. Exciple fused, carbonised, central columella often present, carbonised, simple to reticulate. Ascospores colourless or brown, transversely septate or muriform, I+ blue or rarely I—.

Ocellularia is the largest and most homogeneous group in the Thelotremataceae and comprises c. 200 described species mainly from tropical regions [Hale Smithson. Contr. Bot. 16: 1-46 (1974)]. The carbonised exciple is characteristic for the genus [Hale Bull. Br. Mus. nat. Hist. (Bot.) 8: 297-326 (1981)] and is readily seen when apothecia are sectioned. Two corticolous species are known from New Zealand where the genus is still much in need of study and collection.