Platismatia glauca is a common and widespread species of corticolous (bark-dwelling), foliose lichen in the family Parmeliaceae.

It was first formally described by Carl Linnaeus in his 1753 work Species Plantarum.

[2] William and Chicita Culberson transferred it to the genus Platismatia in 1968.

[3] Platismatia glauca can acclimate to large variations in the availability of environmental nitrogen.

[4] Several secondary metabolites (lichen products) have been isolated from the species, including the nor-triterpene ketone, 30-nor-21α-hopan-22-one, the depsides atranorin and chloroatranorin, and the aromatic compounds methyl β-orcinolcarboxylate and chloroatranol.