Lecanora horiza

It has a distinctly cracked and warted thallus above a white prothallus and glossy orange or brown discs often aggregated into clusters.

Lecanora campestris is similar but can be distinguished with care.

Unless identified by a recognised expert, a photo is required. If the photo doesn't show the key ID features then in the comments box describe the size and identifying characters you have observed.

On bark of deciduous trees, especially mature Ash, Sycamore and Elm. Also on rock, especially vertical calcareous gravestones and brick of churches.

All year round.

Scattered throughout southern Britain and eastern Scotland.

Status in Leicestershire and Rutland not known.