A crustose species with a white to pale grey, scurfy thallus that may be inconspicuous. The apothecia may be sessile or in pits in the substratum. When wet, the discs tend to be red-brown to black, when dry they tend to be chestnut to dark red. The apothecia are often blue-greyish pruinose.
In Scotland, Sarcogyne regularis has mainly a lowland and coastal distribution where it occurs on calcareous rock, including the walls and old mortar found in churchyards. BLS distribution map
scottishlichens.co.uk 