The specific epithet "picta" means "painted or variegated".[2]
Description
Dirinaria picta forms suborbicular to spreading thalli, closely attached to the substrate, and can be saxicolous or corticolous. The lobes are stellate-radiating, contiguous, and pinnatifid to multifid, typically measuring 1-1.5 mm wide. They are generally discrete at the periphery, with acute to rounded apices that are not flabellate confluent.[5][6][2]
The upper surface is glaucous-white to pale grey, smooth, and sometimes faintly pruinose at the apices. Soralia are laminal, capitate, and sparsely distributed, with soredia that are fine and powdery. The lower surface is black. Apothecia are occasionally present, with a disc that is black and subpedicellate. Ascospores are biseriate and measure 12-21 × 5-9 μm.[5][6][2]
Dirinaria picta can be distinguished from Dirinaria applanata by its pinnately or subpinnately divided lobes, which are discrete at the periphery, with narrow to oblong apices. Additionally, the thallus of D. picta is less wrinkled-plicate compared to that of D. applanata.[2]
Substrate
The species Dirinaria picta typically thrives on bark surfaces, a habitat known as corticolous.[5][6][2]
^ abcGalloway D.J. 1985: Flora of New Zealand: Lichens. Wellington: PD Hasselberg, Government Printer. 662 pp.
^ abcGalloway D.J. 2007: Flora of New Zealand: Lichens, including lichen-forming and lichenicolous fungi. 2nd edition. Lincoln, Manaaki Whenua Press. 2261 pp.
Awasthi, D.D. (1975) A Monograph of the Lichen Genus Dirinaria. - Bibliotheca Lichenologica No. 2, J. Cramer, Lehre. 108 pp. (RLL List # 93-3 / Rec. # 1294 - Recent Literature on Lichens) (Illustrations of Dirinaria picta: figs. 42, 43, 44 & 45)
\Brodo, I.M.; Sharnoff, S.D. and Sharnoff, S. (2001) Dirinaria (pp. 305-307) In, Lichens of North America. Yale University Press, New Haven, 795 pages. (Discussion of Dirinaria picta: pp. 306-307; distribution map for North America: p. 306; color photo: p. 307, plate 318)
GASPARYAN A, SIPMAN HJM, LÜCKING R. Ramalina europaea and R. labiosorediata, two new species of the R. pollinaria group (Ascomycota: Ramalinaceae), and new typifications for Lichen pollinarius and L. squarrosus. The Lichenologist. 2017;49(4):301-319. doi:10.1017/S0024282917000226
Kalb, K. (2004). "Dirinaria". In Nash III, T.H.; Ryan, B.D.; Diederich, P.; Gries, C.; Bungartz, F. (eds.). Lichen Flora of the Greater Sonoran Desert Region, Vol. 2. Tempe, Arizona: Lichens Unlimited. pp. 98–103. ISBN0971675910.
Thomson, J.W. (1963) The Lichen Genus Physcia in North America. - Beihefte zur Nova Hedwigia, Heft 7. J. Cramer. viii + 172 pp. (RLL List # 46 / Rec. # 18472 - Recent Literature on Lichens) (Illustration of Dirinaria picta: plate 46)