25 June 2014

A Mediterranean snail Eobania vermiculata (O.F. Müller, 1774) in NW Germany

Tomáš ČEJKA1, Michal HORSÁK2 & Lucie JUŘIČKOVÁ3
(1) Institute of Zoology, Slovak Academy of Sciences, Dúbravská cesta 9, SK-84104 Bratislava, Slovak Republic, e-mail: t.cejka[at]gmail.com
(2) Department of Botany and Zoology, Masaryk University, Kotlářská 2, CZ-61137 Brno, Czech Republic, e-mail: horsak[at]sci.muni.cz
(3) Department of Zoology, Faculty of Science, Charles University, Viničná 7, CZ-12844 Prague 2, Czech Republic

Abstract. Three living individuals and two fresh shells of the Mediterranean snail Eobania vermiculata (O.F. Müller 1774) were found 31 July 2009 at the ruderal site in the centre of the City of Cologne (Köln), Germany. 

Eobania vermiculata (O.F. Müller 1774), a chocolate-band snail, is a snail common in Mediterranean region where it lives in fields, hedgerows, gardens and vineyards. According to Kerney et al. (1983) the species coming in North and Middle Europe just within in S. France (upper Rhône and Garonne valleys), but occasionally adventive elsewhere. But, according to the Bank (2004) and map in Fauna Europaea (Fig. 1) it seems, that E. vermiculata is so widespread now, as a result of intentional and unintentional introductions by humans, that it is difficult to determine its original range. Human spread living individuals of Mediterranean snail Eobania vermiculata were noted from Germany a few times before (e.g. Wiese in verb., Welter-Schultes unpubl.). It is assumed that those individuals came from accidental human-induced spreading and they are not a source for sustainable populations.
Site description, snails sampling
Coordinates: 50°56'29.51"N, 06°59'44.31"E; locality: Germany, Köln, Barcelona-Allee (centre of the town, former stand of the Chemical Factory Kalk); altitude: 42 m a.s.l., habitat: ca. 4-5 m deep gravel-sandy pit (foundation soil?), substrate gravel-sandy (30:70) substrate admixed with building and municipal waste. Slopes and some parts of the building pit were sparsely overgrown by ruderal vegetation (see Fig. 2)
Sampling: Molluscs were sampled by direct searching from beneath the stones, pieces of concrete, boards and other waste for 1 hour by one person.
Results and discussion
Within the frame of the survey of molluscan faunas in large European cities, we found on 31 July 2009 on the Cologne suburb three living individuals and two fresh shells of the snail Eobania vermiculata. All individuals were found beneath one piece (ca. 50 x 30 cm) of concrete (see Fig. 3). E. vermiculata coexists in the site along with numerous population of Candidula intersecta (Poiret, 1801) a and xerophilic snail Monacha cartusiana (O. F. Müller, 1774).
It is likely that individuals found are only part of the small population which probably do not survive the winter season. However, it is noteworthy that in Germany is a regular introduction of this species (Wiese, pers. comm.), such that it is only a matter of time before Introduced populations will acclimatise and survive the cold season. Broadly expected global warming may contribute to enlarge the area of this species.
Funding comes from grant VEGA No. 2/0102/14
Bank, R. A. (ed.) 2004: Mollusca: Gastropoda. Fauna Europaea version 1.1, http://www.faunaeur.org
Fauna Europaea Web Service, 2004: Fauna Europaea version 1.1, Available online at http://www.faunaeur.org
Kerney, M. P. Cameron, R. A. D. & Jungbluth, J. H., 1983: Die Landschnecken Nord- und Mitteleuropas. - Paul Parey, Hamburg u. Berlin, 384 pp. ISBN 3-490-17918-8.

Fig. 1. Present distribution of Eobania vermiculata (O. F. Müller, 1774) in Europe according to Fauna Europaea (2004).

Fig. 2. Habitat of Eobania vermiculata in the suburb of Cologne, Germany.

Fig. 3. Detail of the finding point.

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