Opegrapha calcarea -

Very variable, thallus thin, white or grey to pale pink or rust, usually more or less immersed in the substrate surface; fruit bodies irregularly nodular to slit-like, branched or stellate, lirellate apothecia. Part of a difficult group commonly requiring microscopic examination of the spores for accurate identification.

Often on limestone rocks or mortar, but can be found on other types of rock.

All year round.

Widespread in Britain, particularly common in coastal areas.

Status in Leicestershire and Rutland not known.