The families of British non-marine molluscs (slugs, snails and mussels)


L. Watson and M. J. Dallwitz


Morphology. Snails, with a conspicuous, spiral, univalve shell.

The animal with two pairs of tentacles (but the anterior pair is vestigial). Eyes at the tips of the posterior tentacles.

The shell inoperculate; rising-spiral; 3 whorled; typically dextral; higher than wide; 5–17(–22) mm high; approximately 4.25–7 mm wide; height about 1.6–1.9 x the width; with the body whorl predominating and the spire small and short to high-spired and tapered gradually from the body whorl. The height of the spire about 0.1–0.23 x that of the shell. The spire acute to obtuse. The shell somewhat ovoid-asymmetric, or inverted-pyriform ("succiniform"); deeply sutured. The body whorl moderately convex to very strongly convex. The whorls of the spire moderately convex to very strongly convex. The whorls neither shouldered nor keeled. The aperture round to ovate; with neither teeth nor calluses. The columella smooth. The shell without an umbilicus. The shell thin-lipped; thin and translucent (glossy); amber-coloured or greenish; plain.

General biology, ecology. Terrestrial. In a diversity of damp, natural habitats.


Classification. Gastropoda; Pulmonata.

British representation. “Amber snails”: Catinella (1), Oxyloma (2), Succinea (1).

Illustrations. • Oxyloma pfeifferi, O. sarsi, Succinea oblonga, S. putris (Ellis). • Oxyloma, Succinea (Adams). • Oxyloma pfeifferi, Succinea oblonga, Succinea putris (Reeve).

To view the illustrations with detailed captions, go to the interactive key. This also offers full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, and distributions of character states within any set of taxa.

Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 2005 onwards. The families of British non-marine molluscs (slugs, snails and mussels). Version: 4th January 2012.’.