Pertusaria pseudocorallina (images of British lichens)

Thallus smooth to cracked and warted, pale grey or brownish grey, surface usually isidiate, the isidia brown-tipped, constricted at the base and like minute balloons, breaking away to leave raised, rounded scars resembling minute white apothecia; actual apothecia rare, several per wart. Widespread on base-poor rocks, often common on sea cliffs.

Refs: Smith et al. (2009), 686; Purvis et al. (1992), 458; Dobson (2005), 330 (photo); Dobson (2011), 230 (photo, poorly printed); Allen (2007), 30 (photo); Whelan (2011), 122 (photo); Wirth (1995), 2: 695; Wirth et al. (2004), 229 (photo).

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Images of British Lichens