Flora of New Zealand Series

=Opegrapha saxicola, sensu C.Knight, Trans. N. Z. Inst. 8: 321 (1876). Trans. Linn. Soc. ser. 2, Bot. 1: 280 (1877) non. Ach.

=Opegrapha macquariensis C.W.Dodge, Nova Hedwigia19: 440 (1971) ["1970"].

Holotype: New Zealand. Sine loco [probably Wellington], 1882, Charles Knight [as O. saxicola Ach.] – H-NYL 6597. Isotype – WELT Herb. Knight Vol. 65A: 10, 13, 19 – as Opegrapha litoralis C.Knight  nom. nud. (G. Hayward 1977: 579).

Description : Flora (1985: 326–327).

Chemistry : TLC−, all reactions negative.

N: Northland (Tokerau Beach, Stephenson I., Bay of Islands, Poor Knights Is, Hen & Chickens Is, Rakitu I., Little Barrier I., Great Barrier I.), Auckland (Piha), South Auckland (Onemana Beach, Rabbit I., Motuhora I.), Wellington (Kapiti I.). S: Marlborough (Chetwode Is, Motuara I., Long I., Resolution Bay), Otago (Brighton), Southland (Riverton, Fiordland). St: (Islet Cove Port Pegasus). SN: (SW Promontory). A: Ant.: On coastal rocks, a very characteristic coastal species, in the "white or grey-white zone" above high tide mark. Commonly associating with Pertusaria graphica, Rinodina thiomela and Xanthoria ligulata. Known also from Macquarie I. (Dodge 1971; McCarthy 2003c, 2006).

Endemic

Illustrations : Knight (1876: pl. X, fig. 16A, B; 1877: pl. XXXVIII, fig. 6 – as Opegrapha saxicola Ach.).

Opegrapha diaphoriza is characterised by: the saxicolous habit (coastal rocks); the thick, tartareous, creamish white thallus; prominent black, flexuous (to V-, Y-, or S-shaped), mainly unbranched lirellae, 1–2 × 0.5 mm; and colourless, 3-(5)-septate ascospores, (15–)20–24(–27) × 4–7 μm, slightly constricted at the septa.