Family Helicidae Rafinesque, 1815
This almost exclusively Palaearctic family contains many genera and numerous species, is widely distributed over Europe, east to the Caucasus region, North Africa, the Atlantic archipelagos of Madeira and the Canary Islands, the Arabian Peninsula, the Middle East, and Asia Minor (Schileyko 2006). Only one species, Cepaea hortensis, is native to North America (Pearce et al. 2017), where it is largely restricted to areas immediately along the Atlantic coast. In addition to C. hortensis, four introduced species, belonging to three genera, are established in Canada.
Subfamily Ariantinae Mörch, 1864
Genus Arianta Leach in Turton, 1831
- Arianta Leach in Turton 1831: 35; type species by monotypy: Helix arbustorum Linnaeus, 1758.
Etymology. Named after Ariantas (Greek): king of Scythia, a kingdom in the Ponto-Caspian region of Eurasia.
Arianta arbustorum (Linnaeus, 1758) ♢ Introduced
Subfamily Helicinae Rafinesque, 1815
Tribe Helicini Rafinesque, 1815
Genus Caucasotachea C. R. Boettger, 1909
Caucasotachea vindobonensis (C. Pfeiffer, 1828) ♢ Introduced (Hausdorf et al. 2021)
Genus Cepaea Held, 1837
- Cepaea Held 1837: 910; type species by subsequent designation (Gray 1847): Helix nemoralis Linnaeus, 1758.
Etymology. Greek: Cepaios, of a garden.
Subgenus Cepaea Held, 1837
Cepaea (Cepaea) hortensis (O. F. Müller, 1774)
Cepaea (Cepaea) nemoralis (Linnaeus, 1758) ♢ Introduced
Key to species of Cepaea in Canada
a Peristome dark, purplish brown (in most individuals!*). If the lower spiral band is present, its inner edge is farther from the middle of the base of the last whorl. Dart slightly curved, with blades having bifurcate edges. Each mucus gland usually with 4–5 branches — Cepaea nemoralis
b Peristome white (or with a very pale flush). If the lower spiral band is present, its inner edge is about at middle of the base of the last whorl. Dart straight, with blades having simple edges. Each mucus gland usually with 2–3 branches — Cepaea hortensis
* I haven’t seen pale-lipped C. nemoralis in Canada.
Genus Cornu Born, 1778
- Cornu Born 1778: 371; type species by monotypy: Cornu copiae Born, 1778 (= Helix aspera O. F. Müller, 1774).
Etymology. Latin: a horn. Neuter.
Cornu aspersum (O. F. Müller, 1774) ♢ Introduced
Genus Helix Linnaeus, 1758
- Helix Linnaeus 1758: 645, 758; type species (ICZN 1926, Opinion 94): Helix pomatia Linnaeus, 1758.
Etymology. Greek, helix, a spiral. Feminine.
Helix pomatia (Linnaeus, 1758) ♢ Introduced