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. Eyes at the tips of the posterior tentacles.

The shell inoperculate; rising-spiral; 5.5 whorled; typically dextral; 2.3–3.5 mm in its maximum dimension; wider than high; about 2.3–2.8 mm high (E. fulvus), or 1.6–2 mm high (E. alderi); 2.8–3.5 mm wide (E. fulvus), or 2.3–2.8 mm wide (E. alderi); height about 0.72–0.8 x the width; high-spired and tapered gradually from the body whorl. The height of the spire about 0.31–0.36 x that of the shell. The spire obtuse. The shell cochleate; deeply sutured. The body whorl moderately convex. The whorls of the spire moderately convex. The whorls neither shouldered nor keeled. The aperture lunate; with neither teeth nor calluses. The shell with an umbilicus to without an umbilicus. The umbilicus if not closed, small (minute). The shell thin-lipped (the mouth edge simple); thin and translucent; horn-coloured or pale yellowish brown, glossy or silky-glossy, but appearing almost black in life in the dark-bodied E. alderi; plain. Morphological comments. The body of the animal pale in E. fulvus, dark in E. alderi.

General biology, ecology. Terrestrial. In a wide variety of moist, sheltered, undisturbed habitats - in coniferous and deciduous woods, mossy hedge banks, dune slacks and marshes.


Classification. Gastropoda; Pulmonata.

British representation. Euconulus (2, “Glass snails”).

Illustrations. • Euconulus fulvus: live animal and shells (Taylor). • Euconulus fulvus, with Discidae, Punctidae, Pyramidulidae, Valloniidae, Vitrinidae (Adams).

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.’.