Phylogenetic analyses using molecular data in many cases clarified the relationships of unplaced and misplaced taxa, putting evolutionary trends in many plant groups in a different light and often leading to new insights in generally accepted concepts. We use this approach in the order Piperales to clarify the relationships of Verhuellia. This small and poorly studied genus has generally been treated as closely related or even synonymous to the species-rich genus Peperomia, underestimating its significance in the relationships and evolutionary aspects in Piperaceae and Piperales. Both genera are characterized by some of the most reduced flowers in Piperaceae, superficially similar to each other.

Verhuellia is included in a molecular phylogenetic analysis of Piperales (trnT-trnL-trnF and trnK/matK), based on nearly 6000 aligned characters and more than 1400 potentially parsimony-informative sites. The genus is not part of or sister to Peperomia, as expected, but appears as sister to all other Piperaceae (Zippelia + Manekia and Piper + Peperomia) in all analyses, thereby putting character evolution in this family and in the perianthless Piperales in a different light. A robust phylogenetic analysis including all relevant taxa is presented as a framework for inferring patterns and processes of evolution in Piperales and Piperaceae. Because Verhuellia has some of the most reduced flowers in Piperales, the reconstruction of floral evolution which shows strong trends towards reduction in all lineages needs to be revised.