Family: Verrucariaceae
Hydropunctaria maura (Wahlenb.) C. Keller, Gueidan & Thüs
Tar Lichen
Type: Crustose
Found on rocks as a black, thin crust on the upper shore and just into the splash zone. The surface is crazed and the small apothecia are semi-immersed. Very common
References:
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