An Iberian semi-slug, Drusia valenciennii (Webb & Van Beneden, 1836), was found in 2019 in the Netherlands. When this introduced species was first encountered, only photographs were taken, but a few juveniles were later collected; their raising to maturity is described. One mature specimen was dissected to examine the genitalia and confirm the identification. This is the first record of a Drusia species in northwestern Europe.

, , , , ,
Basteria

CC BY-NC 4.0 NL ("Naamsvermelding-NietCommercieel")

Nederlandse Malacologische Vereniging

M.G.R.M. Inden, C.M. Neckheim, & C.J.P.J. Margry. (2020). Drusia (Drusia) valenciennii (Webb & Van Beneden, 1836) (Gastropoda, Pulmonata, Parmacellidae), a species new for the Netherlands and northwestern Europe. Basteria, 84(4-6), 141–145.