Verrucariaceae Verrucaria viridula Growth type crustose Chemical results negative Common in man-made and natural habitats on calcareous rocks, limestone, mudstone, mortar and bricks. Variable. Large perithecia are half to fully immersed in +/- areolate pale brown thallus. Thallus can also be whitish, grey or green-grey, sometimes +/- immersed and appearing as brown flecks on substrate. Spores simple, 27-34(-40) x 12-22 µm. Similar: Verrucaria nigrescens and Verrucaria macrostoma

Verrucaria viridula
Parkstone and Lytchett heath, Dorset. February 2013 and 2014