Suborder Gymnosomata Blainville, 1824, restricted Spoel, 1976
The suborder Gymnosomata consists of the families Clionidae, Cliopsidae, Notobranchaeidae and Pneumodermatidae.
Molluscs without shell or mantle. The body is usually cylindrical. In some families gills are present as small appendages on the lateral or posterior side of the body. All species have a radula and hooks are present. In some families acetabuliferous arms are found, in others buccal cones are used to capture prey.
[4 families]