Teloschistaceae Caloplaca stillicidiorum Growth type crustose Chemical results: Thallus and apothecial margins K-, disc K+ crimson Can be found growing over mosses and on dead vascular plants on calcareous soils. Photographs on Wild Thyme, Thymus polytrichus. (Previously known as Caloplaca cerina var. chloroleuca). The thallus is greenish-grey, usually scurfy but can be inapparent. Apothecia have thick greyish margins, discs yellowish-orange, sometimes with a greenish pruina. Spores are possibly slightly longer than those of Caloplaca cerina. Microscope photograph below. Similar: Caloplaca cerina

Microscope photograph

Caloplaca stillicidiorum
Ulwell Gap, Dorset. January 2016