The genus is distinguished from its relatives by its unique chemical composition and reproductive features, lacking a substance called atranorin and producing ellipsoidal spores.

While some species reproduce through specialised propagules called soredia or isidia, others form small cup-like fruiting bodies (apothecia) on their surface for reproduction.

The key distinction of this new genus lay in its chemical composition: unlike Physcia, Phaeophyscia lacks the substance atranorin in its outer protective layer (cortex) and produces ellipsoidal conidia (asexual reproductive cells).

[1] Genus Phaeophyscia encompasses a variety of lichen species, characterised by their leaf-like (foliose) structure that often extends in lobes, which can either be short or elongate and tend to lie flat against the substrate, resembling a loosely shrubby form in some instances.

The underside is typically whitish or more commonly black, with matching, simple roots (rhizines) that may extend beyond the lobe tips, giving an appearance similar to cilia.

The reproductive organs (ascomata) are cup-shaped structures (apothecia) found on the lichen's surface, usually encircled by rhizines at their base, with a brown to black disc that lacks a powdery covering.