Sarcogyne regularis (images of British lichens)

Thallus pale, inconspicuous or immersed in the rock surface; apothecia with distinct, black margins but with discs usually densely blue-grey pruinose, chestnut-brown to black under the pruina. Widespread on limestone and other calcareous rocks, mortar and similar substrates.

Refs: Smith et al. (2009), 830; Purvis et al. (1992), 556; Dobson (2005), 400 (photo); Dobson (2011), 405 (photo); van Herk & Aptroot (2004), 344-5 (photo); Wirth (1995), 2: 844, 845 (photo); Wirth et al. (2004), 250 (photo); Puntillo (1996), plate 36 (photo); Thomson (1997), 578-9 (line illus.); Brodo et al. (2001), 650-1 (photo).

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Images of British Lichens