Description of Pseudoneuroterus saltabundus new species (Hymenoptera: Cynipidae: Cynipini) with jumping galls from Italy and revised keys to Western Palaearctic Cynipini genera lacking transscutal articulation

A new species, Pseudoneuroterus saltabundus Sottile & Cerasa sp. nov., associated with a section Cerris oak, Quercus cerris L., is described from Italy. Notably, its galls possess the ability to jump, a behaviour we explore in this study, offering hypotheses on the potential evolutionary advantages this trait may confer. Detailed descriptions, illustrations, and diagnoses of both adults and galls are provided, together with observations on biology, host associations, and distribution. Morphology and molecular data are combined in an integrative approach that provides clear evidence for the recognition and delimitation of this new species. The study also includes a revised key to Western Palaearctic Cynipini genera lacking the transscutal articulation, as well as an updated identification key to Pseudoneuroterus asexual generations, providing a more coherent framework for the placement of the new species. Furthermore, new video evidence confirms the gall jumping behaviour in the congeneric species Pseudoneuroterus saliens.