Mollusca : Gastropoda : Stylommatophora : TruncatellinidaeSnails and slugs

Columella edentula (Draparnaud, 1805)

Toothless chrysalis snail

Columella edentula

Description: Morphologically similar to C. aspera but the yellowish-brown to mid brown shell is narrower and taller, with more whorls (at least 5 when mature, often 6), something which may be recognized in the field. Shell sculpture is finer and less coarse and the surface relatively smooth. Widespread, in marshes and woods. 2.5-3 (-3.5) mm.

World Distribution: Distrution type probably Eurosiberian Wide-temperate (64).

Irish Distribution: Widespread but probably commoner in the south and east.

Ecology:

  • The range of habitats occupied tends towards the more lime-rich and wetter than those of Columella aspera
  • Often found in the leaf litter of wet woodland, in unimproved pasture at the roots of Iris or in neutral to base-rich fens and flushes
  • C. ededentula and C. aspera occasionally occur together in these places

Key Identification Features:

  • A very small, cylindrical, yellow-brown to brown shell
  • Narrower and taller than C. aspera with 5-6 (-7) whorls
  • Shell sculpture more irregular but finer than C. aspera
  • Aperture without teeth
  • Lip thin, simple

Taxonomy:

  • An unusual form which occurs at Ballyaghagan Glen near Cave Hill, north Belfast may be worth investigating further. This has a tall shell (3.5 mm) of 7 whorls which is suggestive of Columella columella or perhaps Columella edentula var. inornata Michaud 1831 (found in the Alpes Maritimes). Columella columella (with 7½ whorls) has a slightly less acuminate apex to the spire and a more cylindrical shell overall. The Ballyaghagan shell has a body whorl which is noticeably broader than the penultimate whorl, a character often attributed to C. columella but not to the var. inornata of C. edentula - something of a puzzle.

Red list status:

  • Least concern (lc).

Distribution Map from NBN: Columella edentula at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Columella edentula at iNaturalist World Species Observations database.

GBIF data for Columella edentula | Classification: Gastropoda, Stylommatophora, Truncatellinidae, Columella

Thumbnails for genus Columella

 Anderson, R., 2024. Columella edentula. (Draparnaud, 1805). [In] MolluscIreland.
https://www2.habitas.org.uk/molluscireland/species.php?item=69. Accessed on 2024-12-26.