Caloplaca dichroa, formerly known as Caloplaca coronata. It consists of areoles which are deeply divided and which rapidly become covered in granules or blastidia as in this photo. It is said to be locally abundant on warm, limestone rocks, but is little known. It was wrongly identified in the past as C. coronata which is a Mediterranean species. I wqas shown it by the Dutch licenologist Andre Aproot in the De Bilt churchyard in the Netherlands, where this photograph was taken. The apothecia at the bottom of the photo are Caloplaca oasis.