Athallia scopularis

About

Athallia scopularis is a species of saxicolous (rock-dwelling), crustose lichen in the family Teloschistaceae. It was first formally described by Finnish lichenologist William Nylander in 1883 as a member of the genus Lecanora. After having been shuffled to several genera in its taxonomic history, it was transferred to the genus Athallia in 2013 following a molecular phylogenetics-led restructuring of the Teloschistaceae. This lichen grows on sun-lit seaside siliceous rocks, particularly those covered with guano from resting birds. It has been recorded from the Atlantic coasts of North America, Northern Europe, and Greenland.

Summary from Wikipedia