Flora of New Zealand Series

Lichen pictus Sw., Nova gen. sp. pl.: 146 (1788).

Thallus suborbicular to spreading, closely attached, saxicolous or corticolous, 4-8 cm diam. Lobes stellate-radiating, contiguous, pinnatifid to multifid, 1-1.5 mm wide, ± discrete at periphery, apices acute, rounded to spathulate, not flabellate-confluent, faintly longitudinally lacunose. Upper surface glaucous-white, pale grey to glaucous-grey, smooth, ± shining, epruinose to fainly pruinose at apices, sorediate. Soralia laminal, capitate, sparsely distributed or frequent, discrete, not confluent, globose, farinose, pale greyish, 0.7-1 mm diam., initially appearing as small warts which later expand, soredia fine, powdery, white or greyish. Lower surface black. Apothecia few to numerous, central, rounded, 0.5-1.5 mm diam., subpedicellate, disc plane to subconvex, black, epruinose, margins thick, entire to subsulcate, concolorous with thallus. Ascospores biseriate, 12-21 × 5-9 µm. Chemistry: Cortex K+ yellow; medulla K-, C-, Pd-. Divaricatic acid and atranorin.

N: Three Kings Is, and other offshore island groups north of Auckland. On pohutukawa bark or rarely on rocks on coastal cliffs.

Pantropical

It is distinguished by the stellate-radiating lobes, which are generally pinnatifid and discrete for the greater part, with apices which are not flabellate-confluent.