[2] The genus was not widely accepted until it was redefined by Mason Hale in the 1970s to include parmelioid lichens with a pored epicortex and narrow, non-ciliate lobes.

[2] Molecular phylogenetics studies have shown that Pseudoparmelia forms a distinct lineage within the Parmeliaceae, closely related to the genera Relicina and Relicinopsis.

[2] The main body (thallus) of Pseudoparmelia has a yellowish tint in both its outer layer (upper cortex) and inner tissue (medulla), caused by the presence of chemicals called secalonic acids.

[2] On the thallus underside, Pseudoparmelia species have a pale surface with simple root-like structures (rhizines) that attach the lichen to its substrate.

A unique chemical feature of the genus is the presence of terphenyl derivatives called butlerins, compounds that are uncommon in lichen-forming fungi but more frequently found in non-lichenised mushrooms and other basidiomycetes.