Xanthoria candelaria (images of British lichens)

Description, based on tabulated characters in Kondratyuk (1997) and on the photographed material:
Minute (1–2 mm in height), foliose but densely tufted and appearing almost fruticose, yellow to deep orange (or grey-yellow in shade), lobes very narrow, to 0.5mm in width, not or little expanded towards the tips, margins and undersurface budding rounded blastidia, 20–35 µm in diameter (microscope), some agglomerated into larger 'conblastidia', 40-110 µm diameter, rhizines absent; apothecia frequent, spermatia (in orange, laminar pycnidia) ellipsoid. Probably widespread on nutrient-enriched trees, fence-posts and rocks, apparently more frequent on the coast, but distribution and occurrence now uncertain due to confusion (both ways?) with the recently described X. ucrainica. See that species for further discussion.

Refs: Kondratyuk (1997); Smith et al. (2009), 969; Dobson (2011), 471. The following generally refer to X. candelaria in the broad sense, but the photographs cited seem likely to be X. candelaria, sens. strict.: Purvis et al. (1992), 645 (might be mixed concept as describes rhizines); Allen (2007), 27 (photo); van Haluwyn et al. (2009), 78-9 (photo); van Herk & Aptroot (2004), 396-7 (photo); Wirth (1995), 2: 972-3 (photo); Moberg & Holmåson (1984), 190 (photo); Holien & Tønsberg (2008), 105 (photo); Brodo et al. (2001), 743 (photo); McCune & Geiser (2009), 395 (photo).

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Images of British Lichens