This species was characterized by its apparently pinnate leaves with separated, irregularly arranged segments, along with a subcapitate inflorescence that becomes shortly cymose in fruit and well developed bracts. Type material shows mature leaves with segments separated along the rachis but young leaves that are not completely pinnate along their length, with their segments connected by wings of lamina tissue along the rachis. In the protologue, Pentagonia imparipinnata was contrasted only with one isotype specimen of Pentagonia gymnopoda, which has leaf segments connected by laminar tissue along the rachis. However, Pentagonia gymnopoda is quite variable in the degree and form of its leaf lobing, as discussed by Taylor in Lorence (2012). Pentagonia gymnopoda has not only variation between plants, but a weak clinal variation from west to east, as also noted by Taylor in Lorence (2012). Plants of Pentagonia gymnopoda from the westernmost parts of Panama have leaves with the lobes more separated from each other and often lacking connecting laminar tissue, and occasional leaves of Pentagona gymnopoda from here resemble those of the type of Pentagonia imparipinnata. The single Colombian plant of Pentagonia imparipinnata was collected along the Caribbean coast not significantly far from the western border of Panama, and it lacks flowers so it cannot be completely evaluated but does not appear at this time to be distinct from Pentagonia gymnopoda. 

Type images in COL at:
http://www.biovirtual.unal.edu.co/en/collections/detail/600450/
http://www.biovirtual.unal.edu.co/en/collections/detail/597752/