Taxonomy

Vertigo (Vertilla) angustior | Narrow-mouthed Whorl Snail

Distribution

Status

Conservation status

HABITATS DIRECTIVE ARTICLE 17 REPORTING
Range
Inadequate
Population
Inadequate
Habitat
Inadequate
Future Prospects
Inadequate
Overall Assessment of Conservation Status
Inadequate
Overall Trend in Conservation Status
Declining
Source: NPWS 2013



IUCN Conservation Status

Ireland (1)Vulnerable [A2c]
Europe (2)Vulnerable [A2ac+3c]
Global (2)Near Threatened
Sources: (1) Byrne, A. et al 2009; (2) Moorkens, E. & Killeen, I. 2011

Legal status

Protected by the following legal instruments:

  • Habitats Directive [92/42/EEC] Annex II

Native status

Native.

Species Biology

Identification

Vertigo angustior is one of two Vertiginid snails in Ireland where the mouth opening of the shell is to the left of the shell (sinistral). The shell is pale brown. The second whorl behind the shell mouth is wider than the whorl immediately behind the shell mouth. Shell length is under 2mm. 5-6 teeth at the shell mouth.

Sources: Cameron R., 2003;. Moorkens, E.A.& Killeen, I.J 2011a.

Habitat

Vertigo angustior is usually present in crumbling, permanently moist vegetation litter, preferably with moss, where the litter is shaded by moderately tall vegetation in open situations. It is more often found on soils that are free draining in areas that are not liable to inundation. It can occur within a number of habitat 'types' but has very specific micro-habitat requirements that limit it's occurence in most instances of the habitat types. Apart from where it occurs in humid dune grassland situations- where it can occur in abundance, it is more likely to occur in the transition zone between a wetter and drier habitat type.

It is mainly coastal, however inland populations do occur.

Source: Moorkens, E. & Killeen, I. 2011a.

Habitats include but are not necessarily limited to;

  • Fixed dunes (CD3)
  • Marram Dunes (CD2)
  • Dune Slacks (CD5)
  • Wet grassland (GS4)
  • Freshwater Marsh (GM1)

Source: Moorkens, E. & Killeen, I. 2011a; Fossitt, J.A. 2001.

Reproduction

There is little available research on reproduction in Vertigo geyeri.

Threats faced

THREAT
ARTICLE 17 CODE
RANKING
Abandonment of pastoral systems, lack of grazing.A04.03High
Intensive grazing
A04.01High
Modification of hydrographic functioning, general
J02.05Medium
Camping and caravans
G02.08Medium
Paths, tracks, cycling tracks
D01.01Low
Car parks and parking areas
D01.03Low

Source: NPWS 2013

In the European IUCN Red List assessment for Vertigo geyeri, in addition to threats that match those identified in the Article 17 report 2013 for Ireland, at a European level the following threats were identified;

  • Eutrophication
  • Pesticides
  • Scrub encroachment
  • Seawall construction and modification
  • Managed retreat of coastal marshes
  • Artificial Planting on open ground
  • Fragmentation of Habitat
  • Motorised vehicular damage to habitats
  • Rise of temperatures and extremes [of weather]
  • Sea level rise
  • Flooding

Source : Moorkens, E. & Killeen, I., 2011.

Conservation actions

In the Article 17 Habitats Directive reporting for the period 2007-2012 no Conservation Measures were outlined other than;

  • Continued legal protection of the species and its habitats inside Natura 2000 sites designated for the species.

Source: NPWS 2013

In the European IUCN Red List Assessment for Vertigo geyeri, the designation of protected sites for the species is noted. Also noted is the necessity for;

  • Active management of habitats within protected areas to ensure they are suitable for the species.

Source: Moorkens, E. & Killeen, I. 2011.

Distribution

World distribution(GBIF)

Mainly a European species, but it also founds in Turkey and Iran.  In Europe if occurs from the south of Scandinavia to the Mediterranean and from Ireland to the Caspian . 

Source:Moorkens, E. & Killeen, I. (2011).

Accuracy of world distribution shown in the Global Biodiversity Information Facility (GBIF) map below will be constrained by, amongst other factors, data held but not shared by countries and organizations not participating in the GBIF.

Irish distribution

Distribution is focused mainly on northern and western coastal areas of Ireland. This is likely due to the amount of fixed dunes in these areas which is one of the species main habitats in Ireland.

Temporal change

Records submitted to Data Centre in 2021

The following map is interactive. If you would prefer to view it full screen then click here.

How can you help

The National BiodiversityData Centre is trying to improve our knowledge on the distribution of Narrow-mouthed Whorl Snail in Ireland. Should you observe this species, please submit sightings to add to the database. Detailed observations will assist us gaining a better insight into where Narrow-mouthed Whorl Snail is most abundant in Ireland and we might also be able to detect regional variations. Please submit any sightings and photographs at:

http://records.biodiversityireland.ie/index.php


All records submitted online can be viewed on Google Maps – once checked and validated these will be added to the database and made available for conservationand research.

Further information

For further information contact Dr. Liam Lysaght llysaght@biodiversityireland.ie

References

Publications

Byrne, A., Moorkens, E.A., Anderson, R., Killeen, I.J. & Regan, E.C. (2009) Ireland Red List No. 2 – Non-Marine Molluscs. National Parks and Wildlife Service, Department of the Environment, Heritage and Local Government, Dublin, Ireland.

Cameron R., (2003) Land Snails in the British Isles. Field Studies Council.

Fossitt, J.A. (2001) A Guide to Habitats in Ireland. The Heritage Council.

Moorkens, E. & Killeen, I. (2011). Vertigo angustior. The IUCN Red List of Threatened Species. Version 2014.2. . <www.iucnredlist.org> Downloaded on 18 September 2014.

Moorkens, E.A.& Killeen,I.J (2011a) Monitoring and Condition Assessment of Populations of Vertigo geyeri,Vertigo angustiorandVertigo moulinsiana in Ireland.Irish Wildlife Manuals,No.55.National Parks and Wildlife Service,Department of Arts,Heritage and Gaeltacht, Dublin, Ireland.

NPWS (2013) The Status of EU Protected Habitats and Species in Ireland.  Species Assessments Volume 3. Version 1.0. Unpublished Report, National Parks & Wildlife Services. Department of Arts, Heritage and the Gaeltacht, Dublin, Ireland.







Images