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 one pair of tentacles only. Eyes at the bases of the tentacles.

The shell operculate; rising-spiral; 3 whorled, or 4 whorled; typically dextral; higher than wide; 3.5–5 mm high; approximately 1.5–1.75 mm wide; height about 2.5 x the width; high-spired and tapered gradually from the body whorl. The height of the spire about 0.5 x that of the shell. The spire truncate. The shell cylindrical; deeply sutured (between all the whorls). The body whorl moderately convex. The whorls of the spire moderately convex. The whorls neither shouldered nor keeled. The aperture with neither teeth nor calluses. The shell thin-lipped; thin and translucent; transmitting the pinkish colour of the animal; plain.

General biology, ecology. Semi-marine. Living around the high tide level, in driftwood, etc., and in salt-marshes.

Classification. Gastropoda; Prosobranchia.

British representation. Truncatella (1, “Looping snail”).

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.’.