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| The families of non-marine molluscs of Britain and Ireland (slugs, snails and mussels) |
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.
Hermaphrodite.
Classification. Gastropoda; Pulmonata.
Representation in Britain and Ireland. Euconulus (2, “Glass snails”).
Illustrations. • Euconulus fulvus: live animal and shells (Taylor). EUCONULIDAE. Euconulus agg., probably Euconulus fulvus (Müller), "Tawny Glass Snail", 2.3–3.5mm. From Taylor (1914). • Euconulus fulvus, with Discidae, Punctidae, Pyramidulidae, Valloniidae, Vitrinidae (Adams). PYRAMIDULIDAE. 1, Pyramidula rupestris (Draparnaud), "Rock Snail". PUNCTIDAE. 2, Punctum pygmaeum (Draparnaud), "Dwarf Snail". VALLONIIDAE. 3, Vallonia pulchella (Müller), "Smooth Grass Snail, Beautiful Grass Snail"; 4, Acanthinula aculeata (Müller), "Prickly Snail"; 5, Spermodea lamellata (Jeffreys), "Plated Snail"). DISCIDAE. 6, Discus rotundatus (Müller), "Rounded Snail, or Radiated Snail"). VITRINIDAE. 7, Vitrina pellucida (Müller), "Pellucid Glass Snail". EUCONULIDAE. 8, Euconulus fulvus agg., probably E. fulvus (Müller), "Tawny Glass Snail". From Adams (1896).
We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or the interactive key, which allows access to the character list, illustrations, 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. See also Guidelines for using data taken from Web publications.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 2005 onwards. The families of non-marine molluscs of Britain and Ireland (slugs, snails and mussels). Version: 5th August 2019. delta-intkey.com’.
