Hydropunctaria amphibia

Hydropunctaria amphibia is a species of saxicolous (rock-dwelling), crustose lichen in the family Verrucariaceae. One of several marine lichens in the genus Hydropunctaria, is widely distributed across Europe, extending from Norway to the Mediterranean and the Iberian coasts, and has a nearly ubiquitous presence along the Catalan coast of Spain. In North America, it is found along the Atlantic Coast from Nova Scotia to the Boston Harbor islands, where its presence in low-pollution areas indicates its potential as a bioindicator for marine lichen community health, and on the west coast in British Columbia, particularly in the Gwaii Haanas's upper littoral fringe. The black, crust-like thallus grows on seashore rocks – both siliceous rocks and limestone – in the lower supralittoral zone, an area also known as the splash zone. Originally described more than two centuries ago as a species of Verrucaria, Hydropunctaria amphibia sets itself apart from other species in Hydropunctaria through ......read more on Wikipedia.