- Helix aspersa O.F. Müller 1774 in 1773–1774: 59.
Identification. Shell subglobose. Spire elevated, conical. Whorlsc. 4½, convex. Periphery rounded. Protoconch smooth. Teleoconch with weak, raised colabral threads, fine spiral striae, and weak malleations. Aperture nearly rounded, without teeth. Last whorl descending when shell full grown. Lip in adults not much thickened but strongly expanded. Umbilicus closed by the broadly expanded lip, or rarely a narrow cleft. Shell opaque, straw-yellow or pale brown with darker brown spiral bands interrupted with irregular pale streaks; lip white. Width to 32 mm (higher than wide).
Comparison. Helix pomatia is larger and banded but without the distinctive pale markings.
Habitat. In BC, in warm places in gardens, along roads, and on vacant, disturbed ground.
Geographic range. This species is introduced to southern BC. It is known to occur on Vancouver Island in Greater Victoria, several mid-island cities, such as Nanaimo, Parksville, and Port Alberni (unpublished), and north to Campbell River (iNaturalist), as well as Salt Spring Island and Metro Vancouver (Forsyth 2004b). This species was first reported from BC by Forsyth (1999). In the USA,
Cornu aspersum is native to the Mediterranean region. Seven clades and origins of c. a. aspersum in North Africa (Sherpa et al. 2018). This differs from the earlier conclusion of Guiller & Madec (2010) who hypothesized a European origin (Tyrrhenian) and spread north in Europe over millennia.
Etymology. Cornu (Latin), a horn. The gender is neuter.Aspersum (Latin), speckled.
Remarks. Although in the past placed in the genus Helix, morphological characters and molecular data show that C. aspersum is not that closely related to the genus Helix, but rather to other genera outside of the tribe Helicini (Nieber et al. 2022; Razkin et al. 2015).
As a large, common European species, with a complex biographical history, and importance as a food item in some countries, the genetics of C. aspersum has received much attention. The complete mitochondrial genome ofc. aspersum was published by Gaitán et al. (2013), and the genetic structure of populations of this species in Europe was studied by Guiller & Madec (2010). Genetic data points to distinct subspecies. Presumably, BC snails belong to the nominotypical subspecies, C. a. aspersum, which is the common, widespread subspecies over most of Western Europe (Sherpa et al. 2018) and the one known to be introduced to North America and other continents (Kougiagka et al. 2022).
References
- Forsyth RG (1999) Distributions of nine new or little-known exotic land snails in British Columbia. The Canadian Field-Naturalist 113: 559–568. https://doi.org/10.5962/p.358656
- Forsyth RG (2004) Land Snails of British Columbia. Royal BC Museum, Victoria, BC, Canada, iv, 188 pp.
- Gaitán-Espitia JD, Nespolo RF, Opazo JC (2013) The complete mitochondrial genome of the land snail Cornu aspersum (Helicidae: Mollusca): intraspecific divergence of protein-coding genes and phylogenetic considerations within Euthyneura. PLoS ONE 8(6): e67299. https://doi.org/10.1371/journal.pone.0067
- Guiller A, Madec L (2010) Historical biogeography of the land snail Cornu aspersum: a new scenario inferred from haplotype distribution in the Western Mediterranean basin. BMC Evolutionary Biology 10: 18. https://doi.org/10.1186/1471-2148-10-18
- Razkin O, Gómez-Moliner BJ, Prieto CE, Martínez-Ortí A, Arrébola JR, Muñoz B, Chueca LJ, Madeira MJ (2015) Molecular phylogeny of the Western Palaearctic Helicoidea (Gastropoda, Stylommatophora). Molecular Phylogenetics and Evolution 83: 99–117. https://doi.org/10.1016/j.ympev.2014.11.014
- Sherpa S, Ansart A, Madec L, Martin M-C, Dréano S, Guiller A (2018) Refining the biogeographical scenario of the land snail Cornu aspersum aspersum: natural spatial expansion and human-mediated dispersal in the Mediterranean basin. Molecular Phylogenetics and Evolution 120: 218-232. https://doi.org/10.1016/j.ympev.2017.12.018
- Kougiagka E, Gkafas GA, Exadactylos A, Hatziioannou M (2022) Morphology and genetic structure profile of farmed snails Cornu aspersum aspersum and Cornu aspersum maximum in Greece. Sustainability 14: 15965. https://doi.org/10.3390/su142315965
- Müller OF (1774) Vermium terrestrivm et fluviatilium, seu animalium infusorium, helminthicorum, et testaceorum, non marinorum, succincta historia. Volumen alterum: testacea. Heineck & Faber, Havniæ & Lipsiæ, xxxvi + 214 + [x] pp. https://doi.org/10.5962/bhl.title.46299
- Neiber MT, Korábek O, Glaubrecht M, Hausdorf B (2022) A misinterpreted disjunction: the phylogenetic relationships of the North African land snail Gyrostomella (Gastropoda: Stylommatophora: Helicidae). Zoological Journal of the Linnean Society 194: 1236–1251. https://doi.org/10.1093/zoolinnean/zlab059
- Razkin O, Gómez-Moliner BJ, Prieto CE, Martínez-Ortí A, Arrébola JR, Muñoz B, Chueca LJ, Madeira MJ (2015) Molecular phylogeny of the western Palaearctic Helicoidea (Gastropoda, Stylommatophora). Molecular Phylogenetics and Evolution 83: 99–117. https://doi.org/10.1016/j.ympev.2014.11.014