The taxonomy of the Palaearctic ant genus Proformica Ruzsky, 1902 is confused and in need of revision. The type specimen for P. nasuta (Nylander, 1856), the type species of the genus, was from Beaucaire, southern France, and is presumably lost. Based on extensive sampling of Proformica nests in southern France, including the type locality, we show that the concept of P. nasuta has been erroneous for more than a century. We integrate information from the morphology of workers and sexual castes, DNA markers, and cuticular hydrocarbons to re-define species in southern France. This allowed us to provide a new, accurate description of P. nasuta and designate a neotype, as well as reference individuals for all castes. In addition, we propose a name, P. longipilosa sp. nov., for a species that since the end of the 19th century has mistakenly been included in P. nasuta.
Ants, Proformica longipilosa sp. nov., Western Palaearctic, molecular markers, cuticular
hydrocarbons.