Recent advances in the taxonomy of the NW European slugs of the genus Arion(Mollusca, Gastropoda, Pulmonata)

Abstract: Many NW European slug species are serious pests in agriculture and horticulture. Asound knowledge of the slug’s life cycle is essential in order to successfully control slugnumbers. However, for many slug species, knowledge of their biology is scarce and insufficientbecause they prove difficult to identify. Many slugs are now considered complexes of siblingspecies whereas several species also show a high intraspecific variation in external and genitalmorphology. Here, we provide an overview on the current knowledge on the morphological,anatomical and molecular characterisation of the NW European species of the land slug genusArion (family Arionidae).