• Xanthoria calcicola Oxner
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Xanthoria calcicola
© Mike Simms
Xanthoria calcicola
© Mike Simms
Xanthoria calcicola
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(Map updated: 11 August 2009)

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At first sight this lichen may seem identical to X. parietina (described elsewhere), a common species of nutrient-rich habitats, whereas X. calcicola is always associated with calcareous substrata such as concrete posts and cement tiles. Unlike X. parietina the centre of the bright yellow-orange thallus of X. calcicola is packed with coarse, granular-shaped outgrowths (isidia). Also, the edge of the disc or exciple in X. calcicola is rough and jagged, but smooth in X. parietina. Throughout Ireland.

Key characteristics

  • Thallus centre covered in sand grain-like isidia
  • Discs slightly raised with jagged, sometimes granular, exciples.

Original text submitted by Vince J. Giavarini

 Simms, M. J., (2016). Xanthoria calcicola Oxner. [In] LichenIreland. Accessed on 2018-08-15.