Folia Historico-Naturalia Musei Matraensis - A Mátra Múzeum Természetrajzi Közleményei 10. (1985)

De Wilde, J. J. — Van Goethem, J. L. — Marquet, R.: The distribution of the species of the genus Deroceras Rafinesque, 1820 in Belgium (Gastropoda, Pulmonata, Agriolimacidae)

D. caruanae is definitely not autochthonous in Belgium. The slug was introduced to Belgium shortly */ before 1968. Most probably there have been a number of subsequent introductions. From 197 2 on, the number of records increased very rapidly, showing an explosive dispersal of this slug. Fourteen years after the first record, D. caruanae became one of our commonest land snails,having been recorded in 57% of the sampled 10 x 10 km squares in Belgium. It is obvious that P. caruanae is a synanthropic species in Belgium and occupies a similar niche as D. reticulatum. This could explain the imposing extension in relation with human activities. At present D. caruanae is more densely distributed than D. laeve except in the Ardennes. For detailed argumentation and conclusions, see J. DE WILDE, J. VAN GOETHÉM & R. MARQUET, 1984a and 1984b. ACKNOWLEDGEMENTS The extensive faunistic and ecological survey on landsnails in Belgium /1977-82/ was granted by the Belgian Fund for Joint Basic Research. REFERENCES ADAM, W. /1947/: Révision des mollusques en Belgique. I. Mollusques terrestres et dulcicoles. - Mém. Mus. r. Hist. nat. Belg., Bruxelles, 106 : 1-298, figs 1-4, pis 1-6, maps 1-162. ADAM, W. /I960/: Mollusques. I. Mollusques terrestres et dulcicoles. - Patr. Inst. r. Sei. nat. Belg., Bruxelles, Faune de Belgique : 1-402, figs 1-163, pis 1-16, maps A-D. DE WILDE, J.J.. , VAN GOETHÉM, J.L. & MARQUET, R. /1984a/: Over de verspreiding in Belgie van de naaktslakken van het genus Deroceras RAFINESQUE, 1820 /Mollusca, Gastropoda, Agriolimacidae/

. - Studiedocumenten van het K.B.I, N., 14 : 1-50, figs 1-12, maps 1-74. DE WILDE, J.J., VAN GOETHÉM, J.L. & MARQUET, R. /1984b/: Sur la distribution en Belgique des limaces du genre Deroceras RAFINESQUE, 1820 /Mollusca, Gastropoda, Agriolimacidae/. - Documents de Travail de l'I.R.Sc. N.B., 15 : 1-50, figs 1-12, maps 1-74. DE WILDE, J.J., VAN GOETHÉM, J.L. » MARQUET, R. - /in press/. Distribution and dispersal of Boettgerilla pallens SIMROTH, 1912 in Belgium /Gastropoda, Pulmonata, Boettgerillidae/

. - Proc

. 8th Int. Malac. Congress, Budapest, 6 pp. , 26 figs. MARQUET, R. - /in press/ An intensive zoogeographical and ecological survey of the land molluscs of Belgium: aims, methods and results /Mollusca : Gastropoda/. - Annls Soc. r. zool. Belg., 115 /2/ : 15 pp. VAN GOETHÉM, J.L. /1974/ : Sur la présence en Belgique de Deroceras caruanae /POLLONERA, 1891/ et de Deroceras agreste /LINNAEUS, 1758/ /Mollusca, Pulmonata, Limacidae/. - Bull. Inst. Sei. nat. Belg., 50 /2/ : 1-21, 1 pi. - /in press/. The E.I.S. Mapping program: Belgium /partim - Proc. 8th Int. Malac. Congress, Budapest, 2 pp. DE WILDE, J.J. - /in press/. On the taxonomic status of Deroceras caruanae /POLLONERA, 1891/ /Gastropoda, Pulmonata/. - Archiv für Moiluskenkunde, 6 pp.

, 1 tab. figs 1-33, VAN GOETHÉM, J.L. Mollusca/. VAN GOETHÉM, J.L. Authors' addresses: J.J. DE WILDE, J.L. VAN GOETHÉM Koninklijk Belgisch Instituut voor Natuurwetenschappen Recent Invertebrates Section Vautierstraat 29 1040 BRÜSSEL R. MARQUET Rijksuniversitair Centrum Antwerpen Laboratorium voor Algemene Dierkunde Groenenborgerlaan 171 2020 ANTWERPEN :

) Regarding its rapid dispersal from 1972 on, it is hardly believable that this slug remained unobserved for a long period. 114