An biennial species with pinnatisect leaves and homostylous flowers. Grows along water sides and broadleaf deciduous forest edges, at low elevations, 900m and below. It previously included P. ranunculoides as a synonym, but research has shown the two to be distinct. Differs from related P. merrilliana in having fewer pinnae, solitary umbels and corolla lobes cuneate-oblong with an emarginate apex.