dcsimg
Image of Geyer's whorl snail
Creatures » » Animal » » Molluscs » Snails » » Whorl Snails »

Geyer's Whorl Snail

Vertigo geyeri Lindholm 1925

Biology

provided by Arkive
This snail has an annual life-cycle, although some may survive into their second year. Up to 10 eggs are laid in late summer, taking two weeks to develop. Adult snails graze on algae and bacteria growing on decaying plant remains (7).
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Conservation

provided by Arkive
All occupied sites in England and Wales are Sites of Special Scientific Interest (SSSIs). Four sites (in north-east England, Perthshire, Wales and north west England) are candidate Special Areas of Conservation (SACs), a site designation that stems from the EC Habitats Directive (5). Geyer's whorl snail is a UK Biodiversity Action Plan (UK BAP) priority species, and as such has a Species Action Plan. This plan aims to maintain the current populations and conduct surveys in an attempt to pinpoint as yet undiscovered populations. The Countryside Council for Wales funded a PhD project, studying the ecology of this species and that of V. angustior, another endangered whorl snail, which was completed in 2001 (6), (8).
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Description

provided by Arkive
This tiny endangered snail is quite similar in appearance to Vertigo genesii but has a more conical shell (2). The shell is pale reddish-brown with regular growth-lines, and the mouth typically has four small peg-like teeth but may have fewer (2).
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Habitat

provided by Arkive
All known populations occur in calcareous flushes; small springs of lime-rich water (5).
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Range

provided by Arkive
Until very recently this species was known in the UK from just two sites in England and one in Wales. Survey work has discovered over twenty further populations including sites in Scotland and Northern Ireland (4). In Europe it occurs in a handful of very scattered sites between northern Sweden, Ireland and south-east Germany and it has an extremely patchy, local distribution throughout this range (5).
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Status

provided by Arkive
Classified as Vulnerable on the IUCN Red List, Endangered on the GB Red List and included in Annex II of the EC Habitats Directive (3).
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Threats

provided by Arkive
The causes of the decline have not been identified, but the snail is vulnerable to trampling, increased grazing and changes in hydrology (3).
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Vertigo geyeri

provided by wikipedia EN

Vertigo geyeri is a species of minute air-breathing land snail, a terrestrial pulmonate gastropod mollusc or micromollusc in the family Vertiginidae, the whorl snails. [3]

The specific name geyeri is in honor of German zoologist David Geyer (1855–1932).

Description

The egg-shaped-oval shell measures just 1.7 to 1.9 mm (0.07 to 0.07 in). in length and 1.2 mm (0.05 in) in width. There are up to five whorls with deep seams. The aperture has four small protrusions (called "teeth") (on parietal one columellar and two palatal), it can also have fewer teeth. The colour of the shell is reddish-brown and the surface is shiny. The shell has regular growth striations and is almost smooth.[4][5]

Habitat

This species lives in constantly wet, calcareous flush-fens that are fed by tufa-depositing springs. In the British Isles (Ireland and United Kingdom) it often lives in association with black bog-rush Schoenus nigricans and yellow sedge Carex viridula, in dense short grasses and sedges with little Sphagnum moss.[6]

Distribution and conservation status

Distribution

Vertigo geyeri is a boreo-alpine species, probably endemic to Europe. It occurs in the boreal, alpine, continental and Atlantic zones with a range extending from Ireland to Russia. Its populations are scattered and local extinctions of isolated populations can occur. It is mentioned in Annex II of the European Union's Habitats Directive.[1]

In the British Isles it is included in the List of United Kingdom Biodiversity Action Plan species, Great Britain (endangered in Great Britain).[7] It occurs in such scattered locations as on Beinn a' Ghlò in Eastern Scotland, in North Yorkshire, in Cumbria and in Corsydd Môn in Anglesey, where there is a large, low-altitude population in a calcareous fen.[6]

It is considered critically endangered in the Czech Republic,[8][9] Its conservation status in Czech Republic in 2004-2006 is bad (U2) in report for European Commission in accordance with Habitats Directive.[10] and it occurs in Denmark, Finland, France, Germany, Latvia, Lithuania, Norway, Poland, Slovakia, Ukraine,[11] Sweden and Switzerland.[1]

References

  1. ^ a b c Killeen, I.; Moorkens, E.; Seddon, M.B. (2011). "Vertigo geyeri". IUCN Red List of Threatened Species. 2011: e.T22940A9400082. doi:10.2305/IUCN.UK.2011-2.RLTS.T22940A9400082.en. Retrieved 20 November 2021.
  2. ^ (in German) Lindholm W. A. 1925. Studien an palaearktischen Vertigo-Arten. Archiv für Molluskenkunde 57 (5/6): 241-251.
  3. ^ MolluscaBase eds. (2023). MolluscaBase. Vertigo geyeri Lindholm, 1925. Accessed through: World Register of Marine Species at: https://www.marinespecies.org/aphia.php?p=taxdetails&id=1050662 on 2023-02-08
  4. ^ "Vertigo geyeri Lindholm, 1925". AnimalBase. Retrieved 15 March 2020.
  5. ^ "Vertigo (Vertigo) geyeri LINDHOLM, 1925". Uniwersytet im. Adama Mickiewicza w Poznaniu. Archived from the original on 6 March 2005. Retrieved 15 March 2020.
  6. ^ a b "Geyer's whorl snail Vertigo geyeri". JNCC. Retrieved 15 March 2020.
  7. ^ 2001–2007. Action plan for Vertigo geyeri. UK Biodiversity Action Plan, Joint Nature Conservation Committee
  8. ^ "Evropsky významné lokality v České republice" (in Czech). 2003.
  9. ^ "Red List of the molluscs (Mollusca) of the Czech Republic". 2006-07-14.
  10. ^ (in Czech) Dušek J., Hošek M. & Kolářová J. (2007) Hodnotící zpráva o stavu z hlediska ochrany evropsky významných druhů a typů přírodních stanovišť v České republice za rok 2004-2006. - Ochrana přírody, 62(5): appendix 5:I-IV.
  11. ^ Balashov I. & Gural-Sverlova N. 2012. An annotated checklist of the terrestrial molluscs of Ukraine. Journal of Conchology. 41 (1): 91-109.
  • Bank, R. A.; Neubert, E. (2017). Checklist of the land and freshwater Gastropoda of Europe. Last update: July 16th, 2017
Wikimedia Commons has media related to Vertigo geyeri.
license
cc-by-sa-3.0
copyright
Wikipedia authors and editors
original
visit source
partner site
wikipedia EN

Vertigo geyeri: Brief Summary

provided by wikipedia EN

Vertigo geyeri is a species of minute air-breathing land snail, a terrestrial pulmonate gastropod mollusc or micromollusc in the family Vertiginidae, the whorl snails.

The specific name geyeri is in honor of German zoologist David Geyer (1855–1932).

license
cc-by-sa-3.0
copyright
Wikipedia authors and editors
original
visit source
partner site
wikipedia EN