Slugs with an internal shell which is usually degenerate ... none have a keel, and all have a caudal mucous gland just above the top of the tail. The mantle is shagreened but not grooved. The respiratory pore is on front of the mid-point of the mantle.
Distribution holarctic, but typical members confined to Europe. Generally herbivorous. Most identifiable on external characteristics, but some work by specialists is showing that some spp. are aggregates of several closely related species.
Medium slug, 5-7cm, usually dark brown with single darker longitudinal band on each side, which passes above and below the respiratory pore. Mantle usually slightyly paler than rest of body. Shows considerable variation in internal anatomy and may possibly include more than one species.