Cecilioides acicula

Cecilioides (Cecilioides) acicula (O. F. Müller, 1774)
Blind Awlsnail

  • Buccinum aciculum O. F. Müller 1774: 150.
  • Many additional synonyms in Europe.
Cecilioides acicula
Cecilioides acicula, Ontario.

Identification. Shell very elongate. Spire tall, slender, sides almost straight. Apex bluntly rounded. Whorls flatly rounded; periphery rounded. Suture shallow, with a “false suture” below. Protoconch smooth. Teleoconch smoothish, glossy, with weak incremental lines. Aperture narrow, acute above, edentulous. Outer lip thin, simple. No umbilicus. Columella truncate below. Shell translucent, clear but opaque and whitish when weathered. Height to 5.5 mm (higher than wide).

Animal white and eyeless (blind).

This species is unique among land snails in Canada for its very slender and colourless or whitish shell.

Habitat. Mostly subterranean, this species lives underground at depths to 2 m or more, but it may also occur near the surface under debris under (such as old bricks around a greenhouse; Einsohn 1981). In Canada, so far it has only ever been found in stream drift, but presumably is living in nearby. Difficult to locate alive, shells are more likely to be found dead in stream drift (Kerney 1999). In Europe and elsewhere, it occurs in in open calcareous habitats, such as dry pastures, other grassy places, quarries, at the bases of walls, on cliffs, and in screes (Ellis 1969, Kerney 1999). It has been found in cemeteries and graves, where old bones may provide a source of calcium (Herbert & Kilburn 2004, Georges & Charlier 2010). Cecilioides acicula has been intercepted entering the USA in soil and on bulbs and other plants (Dundee 1974).

Global range. Probably originally native to the Mediterranean region; now widespread in Central and Western Europe, Asia Minor, Arabia, and North Africa; east through Crimea, Caucasus, Central Asia from Köpet Dagh to Pamiro-Alai (Kerney & Cameron 1979, Kerney et al. 1983, Kantor et al. 2010, Sysoev & Schileyko 2009); Ukrainian Ciscarpathia, and Transcarpathia (Sverlova 2006). Now introduced to South Africa, New Zealand, Australia, Bermuda, Barbados, Argentina; USA, including Hawaii, and Canada. In the continental USA, this species has been found in Maryland, New Jersey, New York (Einsohn 1981), Pennsylvania, Virginia, Florida, New Mexico, Texas, and California (Pilsbry 1946, Roth & Sadeghian 2006, Örstan 2007, NatureServe 2009).

Canadian range. Introduced to southern Ontario; although presently known only from drift of the Grand River and Bowmanville Creek, a small stream east of Toronto (Forsyth et al. 2008). Although living animals are unknown, this is not unexpected for a mostly subterranean species (Kerney 1999, Forsyth et al. 2008); established populations out of doors are likely. Specimens were recovered in drift from two separate drainages, which implies broader occurrence in southern Ontario.

Etymology. Latin, acicula, a small pin.

References.

  • Ellis AE (1969) British snails. A guide to the non-marine Gastropoda of Great Britain and Ireland, Pleistocene to Recent. Oxford University Press, Oxford, 298 pp., 14 pls.
  • Forsyth RG, Oldham MJ, Schueler FW (2008) Mollusca, Gastropoda, Ellobiidae, Carychium minimum, and Ferussaciidae, Cecilioides acicula: distribution extension and first provincial records of two introduced land snails in Ontario, Canada. Check List 4: 449–452.
  • Georges P, Charlier P (2010) Localisation préférentielle de Cecilioides acicula (O. F. Müller, 1774) dans deux tombes hellénistiques de Plinthine (Egypte). MalaCo 6: 298-302.
  • Kerney M (1999) Atlas of the land and freshwater molluscs of Britain and Ireland. Harley Books, Colchester, Essex, U.K., 264 pp.
  • Müller OF (1774) Vermium terrestrium et fluviatilium, seu animalium Infusorium, Helminthicorum, et Testaceorum, non marinorum, succincta historia. Volumen alterum: Testacea. Heineck & Faber, Havniæ & Lipsia, xxxvi + 214 + [x] pp.
  • Sysoev A, Schileyko A (2009) Land snails and slugs of Russia and adjacent countries. Pensoft, Sofia/Moscow, 212 pp. + 142 pls.