Order: Verrucariales       Family: Verrucariaceae Species: Placidium squamulosum Previously Catapyrenium squamulosum. Growth type squamulose. Photos: On limestone. Black Head, the Burren, and Askeaton, Co. Limerick, Ireland. Adpressed squamules are buff to red-brown with felted black undersides. Immersed brown perithecia with blackish ostioles. The asci are 8-spored, spores simple, 12-16 x 5.5-7.5 µm. S Local, often coastal distribution in Ireland in crevices in hard calcareous rocks and walls. Also on mortar and calcareous soil. Chemical reactions negative

Top image above Placidium squamulosum Askeaton, July 2009. Identified by B Coppins