Opegrapha calcarea

Revised name: Arthonia calcarea

This crustose species has a white, green-pink, pink, grey-pink or buff thallus that can also be immersed. Though the disc usually remains a slit, the unbranched or stellate lirellae are often characteristically clustered in heaps.

Thallus: C-, K-, UV-

In Scotland, Opegrapha calcarea has a mainly coastal distribution where it is found on damp, shaded rock. Further inland, it can be found on basic rock such as gravestones. BLS distribution map