Helix pomatia Linnaeus, 1758
- Helix pomatia Linnaeus 1758: 771.
- Many additional synonyms in Europe.
Identification. Shell subglobose. Spire elevated, conical. Whorls ca 4, convex. Periphery rounded, medial on the last whorl. Protoconch smooth. Teleoconch with irregular, low colabral ridges/riblets and spiral rows of weak granules. Aperture large, subovate-rounded, inside showing external shell colour, without teeth. Last whorl descending when shell full-grown. Lip not scarcely thickened in adults, narrowly flared outward, more strongly expanded near the columella. Umbilicus closed or a narrow cleft. Shell opaque, pale grey-brown, with lighter and darker colabral streaks and, in general, 2–5 spiral bands (sometimes rather weakly marked or absent); columellar lip pinkish. Width to 42 mm (higher than wide).
Habitat. In parks and gardens.
Canadian range. Introduced. Southern British Columbia: Melrose and Revelstoke. Southern Ontario: Sarnia. Populations are apparently reproducing (Forsyth & Kamstra 2019).
Etymology. Greek, poma, “a lid” (Kennard & Woodward 1926), perhaps in reference to the calcified epiphragm used to close the aperture during times of aestivation or hibernation.
- Forsyth RG, Kamstra J (2019) Roman Snail, Helix pomatia (Mollusca: Helicidae), in Canada. The Canadian Field-Naturalist 133: 156–159.
- Kennard AS, Woodward BB (1926) Synonymy of the British non-marine Mollusca (Recent and post-Tertiary). British Museum (Natural History), London, xxiv + 447 pp.
- Linnaeus C (1758) Systema naturæ per regna tria naturæ, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio decima, reformata. Laurentii Salvii, Holmiæ,  + 824 pp.