Upper surface bright green when wet, brown-grey when dry, with adpressed, convex, laminar cephalodia which cannot readily be detached. The lower surface has a network of veins which are dark towards the bases of the lobes. Scotland is the stronghold for this species which is widespread but not common. Found in mossy, calcareous, coastal and upland habitats

References: 
Smith, C.W. et al. editors (2009) The Lichens of Great Britain and Irelandd
Dobson, F.S. (2018) Lichens: an Illustrated Guide to the British and Irish Species
Ahlti et al. editors (2012) Noric Lichen Flora. Volume 3: Cyanolichens