Dichotrachelus pesarinii sp.n., a missing link between the species from the central and the western southern Alps (Coleoptera: Curculionidae: Cyclominae)

A new species of Dichotrachelus associated with Saxifraga caesia is described, D. pesarinii sp.n., and a phylogenetic analysis is carried out based on morphological and molecular mtCOI data. The new species resolved as the sister group of the D. sulcipennis group, whose members are associated with Saxifraga oppositifolia. This placement suggests that this group differentiated in the central southern Alps, and that the new species represents an evolutionary link between the species from the central and eastern southern Alps and those from the western Alps. The evolution of the association of Dichotrachelus with particular Saxifraga species remains contradictory; scenarios are proposed.