Diploschistes scruposus (Schreb.) Norman
Lichen scruposus Schreber, Spic. fl. lips.: 133 (1771).
Thallus pale to dark grey, sometimes with a yellowish tinge, roughened, warted-areolate, irregularly spreading or ± suborbicular 1-5 cm diam., saxicolous. Apothecia urceolate at first, emerging and opening out to reveal small, black, ± pruinose discs, proper margin visible within a thalline margin. Hypothecium black. Ascospores at first 5-septate becoming muriform, 22-40 × 10-18 µm. Chemistry: thallus K+ yellow, C+ red. Diploschistesic and lecanoric acids.
S: Otago (Mt Watkin, Maungatua). Subalpine to alpine rocks. Probably more widely distributed in Canterbury, Central Otago and Marlborough east of the Main Divide.
Cosmopolitan
