Invasion

Invasion Description

1st record: Scotland/Firth of Forth (1979, Elliott and Kingston 1987, cited by Bastrop et al. 1998) At least two species of Marenzelleria have been introduced to the Baltic and North Seas, but the taxonomy of the group is confused. Sikorski and Bick (2004) identify North Sea estuary animals as M. viridis and Baltic animals as M. neglecta , a newly described Northwest Atlantic native species. Bastrop and Blank (2006), using molecular methods, support report occurrences of both species in the Baltic, together with a third, M. arctia, native to the Arctic Ocean.

Geographic Extent

Scotland/Firth of Forth (1979, Elliott and Kingston 1987, cited by Bastrop et al. 1998); Scotland/Tay Estuary (1986, Atkins et al. 1987); Govan Wharf, Glasgow/Scotland.Clyde Estuayr (O'Reilly and Nowacki 2019); Ghent/Belgium/Scheldt estuary (1995, Ysbaeert et al. 1997; Soors et al. 2013); Netherlands/Ems estuary (1982, Essink 1997); Balgzand/Netherlands/Wadden Sea (1989, Beukema and Dekker 2011, rapid increase in abundance and distribution, 1987-1995); Germany/upper Elbe estuary (1985, Essink 1997; Bastrop and Blank 2006); Denmark/Ringkobing Fjord (Bastrop and Blank 2006); Germany/Weser estuary (1986, Sikorski and Bick 2004); Rømø/Denmark/North Sea (2010, Delefosse et al. 2012); Nissum Bredning/Denmark/Limfjord (2010, Delefosse et al. 2012); Denmark/Hjarbæk Fjord, branch of Limfjord (2010, Delefosse et al. 2012)