Aristolochia keratuma (Aristolochiaceae), a new species of the series Thyrsicae from Choco (Colombia), and key to identify its species

A new species of Aristolochia series Thyrsicae is here described and illustrated. The series to which the new species belongs is a monophyletic group that comprises 19 species distributed from Mexico to Bolivia and central Brazil. So far, all the specimens of the new species have been collected in the central region of the departament of Choco, Colombia. Additionally, an identification key is provided along with illustrations of the flowers of all the species in the series, and the synapomorphies of the new species are illustrated.