Physcia aipolia (Ehrh. ex Humb.) Fürnr.
Foliose lobes lobe surfaces with distinct white flecks (pseudocyphellae), without soralia and marginal cilia. Apothecia with brown to black, thinly pruinose discs. Grows on a variety of tree species in situations of good light.
Smith et al. editors (2009) The Lichens of Great Britain and Ireland
Dobson (2018) Lichens: an Illustrated Guide to the British and Irish Species