Flora of New Zealand Series

Lectotype: New Zealand. Otago, Hyde, at 400 m on quartz, J.S. Thomson T 2328 [A 41 – CHR 374335 (fide Galloway [1985a: 50])]. Isolectotype – OTA.

Description : Flora (1985: 50)

S: Canterbury (Waimakariri riverbed), Otago (Poolburn, Lake Onslow, Hyde, Stoneburn), Southland (S Mavora Lake, Tiwai Point). St: (Port Pegasus, Cooks Arm). On sunny tops of rocks and pebbles (quartz, schist, granite and greywacke) and on rock outcrops in grassland. Associating with Candelariella vitellina, Lecidea fuscoatrula, Rhizocarpon geminatum, R. geographicum, R. lecanorinum, R. submodestum, Xanthoparmelia mougeotina.

Endemic

Buellia macularis is characterised by: the saxicolous habit; the very closely attached thallus almost immersed in the quartz; the fine, black, stellate, marginal prothallus, reminiscent of Cystocoleus; the grey-white, minutely areolate thallus (appearing maculate); centrally clustered, innate to sessile, black apothecia; ellipsoidal to ovoid ascospores, apices round or pointed, straight, or slightly curved, ±fabiform, slightly constricted at septum, 12–16 × 6.6.5 μm. On flat stones in riverbeds and on the tops of flat schist plates in grassland, the species often forms extensive patches of round to irregular, interlocking thalli.