Basionym: Lichen parietinus L., Sp. Pl. 2: 1143 (1753)
Synonym: Index Fungorum
Protolog: Data lacking.
Type locality: In Dillenius, (1742: tab. XXIV, fig. 76A) - lectotype selected by Jørgensen, James & Jarvis (1994: 379); epitype [the corresponding specimen in OXF-Dillenius] (selected by Jørgensen et al., loc. cit.).
Barcode: Data lacking.
Coordinates: Data lacking.
Thallus: 25-43-100 mm diam., mostly well delimited and regular, yellow to orange, shade forms green-grey. Marginal lobe ends at the outermost tips 0.4 - 0.8 - 1.6 mm wide, at the widest point 1.5 - 2.9 - 6.0 mm wide, and just inside the widest point 0.9 - 1.7 - 3.1 mm wide. Marginal lobe tips branched, spathulate to flabellate. Specialized vegetative laminar structures absent. Upper surface somewhat wrinkled, smooth to shiny, crystals absent. Thallus 143 - 236 - 291 thick. Medulla with hyphae in bundles. Apothecia almost always present, abundant, 0.7 - 1.82 - 4.5 mm diam., thalline margin mostly + smooth. Pycnidia abundant, immersed to somewhat protruding. Conidia ellipsoid (Lindblom & Ekman 2005: 195).
Photobiont: Trebouxia spec. (Huber et al. 1994: 317).
Chemistry: Choline sulphate (C. F. Culberson 1969). Allantoin (Solberg 1971). xxx (Garegg et al. 1973). Allantoin, choline sulphate, taurine, xantholamine, 0-α-D-Galactopyranosyl-(1 → 6)-0-ß-D-galacto-pyranosyl-(1 → 1)-D-glyceritol, 1-0-β-D-Galactopyranosyl-D-ribitol (Huneck & Yoshimura 1996: 126, 127, 130, 132). "Chemosyndrome A" (Lindblom & Ekman 2005: 195). xx (Steiner & Hauschild 1970). xx (Søchting 1997). Upper surface K+ purple, C-, KC-, P-; parietin (major), fallacinal, emodin, teloschistin, parietinic acid. (Nash et al. 2001: xx).
Ecology: In Maine, the distribution of Xanthoria parietina closely parallels the distribution of salt aerosols presumably emanating from the nearby ocean shore (Hinds 1995, Brodo et al. 2007: 304). In the Sonoran area most common on twigs (but also found on volcanic rocks), also occurring on bark, rock, as well as various other substrates (subneutral to basic, rather nutrient rich), often in humid microclimates, such as coastal regions.
Molecular data: Genbank
Distribution: - Despite being one of the most common species in Europe and occurring in Australia, Africa and Asia, Xanthoria parietina was narrowly confined to coastal areas in North America (Hinds 1995, Lindblom 1997), and is apparently only recently invading inland (Brodo et al. 2007). Database
Note: The statement "This species occurs more or less world-wide" (Lindblom 1997) is not correct.