New record of Pachodynerus nasidens (Vespidae) on Madeira

This dataset documents the first confirmed record of the Neotropical potter wasp Pachodynerus nasidens (Latreille, 1817) in the western Palaearctic region, based on specimens collected on Madeira Island. Native to the Americas, P. nasidens has demonstrated a remarkable capacity for range expansion, with established populations in several Pacific islands, Japan, and Australia. Its detection in Madeira represents the first occurrence of this species in the western Palaearctic, the first introduced species of Vespidae recorded on Madeira Island, and only the second in Macaronesia. The introduction of P. nasidens is likely linked to human-mediated transport, particularly via aviation and maritime activities, which facilitate dispersal across oceanic barriers. The species’ notable nesting plasticity—allowing it to exploit pre-existing cavities, abandoned nests of other wasps, and various artificial structures—is considered a key factor underlying its successful establishment in novel insular environments. These findings contribute new data on the distribution of Vespidae in Macaronesia and highlight the importance of monitoring non-native Hymenoptera in oceanic islands. Given Madeira’s high level of endemism, further research is needed to evaluate the potential ecological impacts of P. nasidens, particularly its possible interactions and competition with the endemic cavity-nesting wasp Ancistrocerus madaera (de Saussure, 1853).