First report of the oriental shrimp <Emphasis Type="Italic">Palaemon macrodactylus</Emphasis> Rathbun, 1902 (Decapoda,Caridea, Palaemonidae) from German waters

The native East Asian shrimp Palaemon macrodactylus has become a common inhabitant of estuaries along the Pacific coast of North America. More recently (documented since 1999), the species has also been colonising European waters and has been reported from Spain, England, Belgium and the Netherlands. In this study, we present a chronology of the reported introductions of this species and provide the first detailed report of its occurrence in German waters. P. macrodactylus was found in the Geeste river mouth (Weser Estuary) as well as in Hooksiel, north of Wilhelmshaven between 2004 and 2005. We assume its presence in other estuarine habitats of the North Sea and predict its introduction into the Baltic Sea.