de Montfort, 1810
External shell stout, relatively solid, able to accommodate the animal during defensive retraction, consisting of up to 8 whorls. Horny operculum present.
Cephalic shield forming a pair of antero-lateral lobes, and a pair of postero-lateral flaps which may conceal part of the shell. Parapodial lobes not developed. Posterior pallial lobe inconspicuous; mantle prolonged inside the shell to form a spiral caecum. Gill present in mantle cavity. Penis large, non-retractile.
Gizzard plates absent. The radula in the North Atlantic species consists of a large number of exceptionally small teeth. Nervous system streptoneurous.
Source: Thompson, 1988.
The following species occurs in the region:
Acteon tornatilis