Aspicilia leprosescens (images of British lichens)

Thallus grey, cracked into papillate areoles, the margins of which can become raised and minutely almost squamulose; apothecia usually sparse or absent, set in the thallus, discs black. Widespread on rocky coasts, often common where sea-birds perch, very rarely on exposed rocks inland.

Refs: Smith et al. (2009), 186; Purvis et al. (1992), 99; Dobson (2005), 75 (photo); Dobson (2011), 81 (photo); Allen (2007), 14 (photo); Whelan (2011), 52 (photo); van Herk & Aptroot (2004), 68-69 (photo).

lastdragon.org

Images of British Lichens