Lecania aipospila (Wahlenb.) Th. Fr.
Widespread on rocky coastal habitats but not common. Found on the tops of rocks that have been nutrient-enriched, usually by birds. Distinctive coarsely warted thallus, often indistinctly lobed, and with apothecia on stalks
Smith, C.W. et al. editors (2009) The Lichens of Great Britain and Irelandd
Dobson, F.S. (2018) Lichens: an Illustrated Guide to the British and Irish Species