Xanthoria calcicola (images of British lichens)

Foliose, yellow to orange, resembling the common Xanthoria parietina but with the thallus surface densely covered with coralloid isidia; apothecia generally sparse or absent. Widespread but predominantly south-eastern, on calcium-rich stonework and mortar, sometimes on dust-impregnated fencing.

Refs: Smith et al. (2009), 969; Purvis et al. (1992), 647; Dobson (2005), 461 (photo); Dobson (2011), 471 (photo); van Herk & Aptroot (2004), 394-5 (photo); Arup et al. (1997), 237 (photo); Thor & Arvidsson (1999), 338 (photo), 519; Wirth (1995), 2: 972 (photo), 973; Wirth et al. (2004), 154 (photo).

The name 'Xanthoria aureola' has been and continues to be widely used for this species, though the name is now considered the 'correct' name for the coastal lichen previously known as X. ectaneoides. It will continue to be a source of confusion and would be better rejected [ICBN art. 57.1].

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Images of British Lichens