Catillariaceae Solenopsora candicans Growth type placodioid Chemical results: K-, C-, KC-, P+ orange, UV+ grey Sunny, hard calcareous rocks, often found on limestone monuments. Rosette-forming white to whitish-grey thallus, thickly pruinose with a blue-black prothallus. The lobes are slightly convex, widening towards the tips. The apothecia have black, usually pruinose discs, the margins becoming excluded. Asci 8-spored, spores 1-septate, 10-18 x 3-4 µm. Similar: Diploicia canescens is sorediate, rarely fertile. K+ yellow, P-. Solenopsora liparina is very rare, and only found on coastal serpentine rocks in Cornwall

Solenopsora candicans
On concrete block, Studland, Dorset. September 2012