The distribution of this species is Atlantic (the part of the Palearctic area which is under the direct climatic influence of the Atlantic Ocean), and southern-European.[5]
This small snail occurs across Europe as far north as southern Sweden.[6]
Within Western Europe, only the populations in England (Great Britain) and Ireland are considered to be viable,[6] although further populations exist in the Czech Republic (critically endangered, occupying the White Carpathians Biosphere Reserve, Kokořínsko Landscape Protected Area and Southern Moravia),[7][8][9] in Poland (critically endangered)[10] and elsewhere in Europe (for example: Netherlands,[11]France).[12] Its conservation status in the Czech Republic in 2004–2006 was described as favourable (FV) in the report for the European Commission in accordance with the Habitats Directive.[13] Its conservation status in Spain is endangered and it occurs in two localities only: near Estañá lake and near Lake of Banyoles.[14]
In the United Kingdom, Desmoulin's whorl snail is listed as endangered, although it occurs in a number of areas in a band from Norfolk to Dorset, with outlying populations in Kent and the Llŷn Peninsula in North Wales[6] and has probably been under-reported in the past because of its minute size. Its presence on the site of the planned Newbury bypass caused the building of that road to be postponed; the building works were able to go ahead once the snails had been moved to a new habitat nearby. It is reported to have since died out at the new site,[19][20] but the same report states "Desmoulin's whorl snail is now considered less scarce than it was 10 years ago".
Shell description
The shell is dextral, minute, ovate, ventricose, obtuse at the apex, smoothish, subperforate. The aperture is semiovate, four-toothed, with one tooth on the parietal wall, another on the columella, and two palatals, the lower one longer. The shell has four whorls, parted by a distinct suture, the last doubly larger than all the others together. It is rather solid, glossy, subpellucid and of a uniform fulvous color.[21]
The shell of this species reaches about 3 mm in length. The shell is yellowish or brownish and translucent.[22]
This article incorporates public domain text from reference.[21]
^ abKilleen I., Moorkens E. & Seddon M. (2012). "Vertigo moulinsiana". In: IUCN 2012. IUCN Red List of Threatened Species. Version 2012.2. <www.iucnredlist.org>. Downloaded on 1 November 2012.
^Dupuy D. (1849). Catalogus extramarinorum Galliae testaceorum brevioribus specierum nondum descriptorum diagnosibus. pp. 1–4, p. 4, No. 248, Paris.
^(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 přírody62(5): appendix 5:I-IV.
^Ramos M. A. (1998). "Implementing the habitats directive for mollusc species in Spain". Journal of Conchology, Molluscan Conservation: A Strategy for the 21st Century, Special Publication 2: 125–132.
^Balashov I. & Gural-Sverlova N. 2012. An annotated checklist of the terrestrial molluscs of Ukraine. Journal of Conchology. 41 (1): 91–109.
Dupuy D. (1849). Catalogus extramarinorum Galliae Testaceorum in opere cui titulus Histoire naturelle des Mollusques terrestres et d'eau douce qui vivent en France descriptorum. 4 pp.
Sysoev, A. V. & Schileyko, A. A. (2009). Land snails and slugs of Russia and adjacent countries. Sofia/Moskva (Pensoft). 312 pp., 142 plates.