Palicourea bangii is characterized by its pilosulous to glabrescent vegetative and reproductive structures; medium-sized, petiolate leaves with elliptic blades; stipules with the distinctive form found in this species group and lobes 5-8 mm long; pedunculate, paniculiform inflorescences with the flowers subsessile in short cymes; relatively short, deeply lobed calyx limbs ca. 0.5-1 mm long with the lobes generally all equal; funnelform, white to pale yellow corollas with the tube 4-5.5 mm long and lobes 1.5-2 mm long with a rounded abaxial thickening; obovoid fruits 4-5.5 × 4-5.5 mm; and pyrenes with well developed, rounded, abaxial ridges. The stipules of this species change in form with age as described above for this species group, with this change particularly well marked in this species. The stipule lobes are thin-textured, and asymmetrically broadened on the petiolar side. These lobes are shortly erose along the margins on their upper portion, and these filamentous segments appear to be glandular at their tips when young.
Palicourea bangii is similar to several other species found in Peru and Bolivia, and the circumscriptions of some of these were clarified by Taylor (2019). See the page for Palicourea tristis for a key that outlines their distinctions.