A crustose species with a white to light grey thallus that is slightly shiny and smooth or warted. If present, the apothecia are flesh-coloured to light brown but they become darker with age. The disc is often pruinose and there is a slightly lighter, thin margin. The thallus also carries many small, black, dust-like pycnidia.
Thallus: K+ yellow
In Scotland, Cliostomum griffithii is widespread on the drier sides of mature trees, including conifers in rather dry, well-lit situations. BLS distribution map
scottishlichens.co.uk 