摘要：The Baltic palaemonid fauna comprises four species: Palaemonetes varians, Palaemon adspersus and two newcomers, P. elegans and P. longirostris. The first three species have been reported from Polish waters. This paper presents the history of faunal change associated with P. elegans recent colonization along the Polish Baltic coast, its estuaries, coastal lakes and lagoons. The oldest record of P. elegans comes from the Vistula deltaic system collected in 2000. Presumably moving eastwards from the Atlantic, the species colonized and formed a vivid, reproducing population all along the studied part of the Baltic shores. In many places it has replaced the native P. adspersus and it has became an abundant element of the palaemonid community in the Gulf of Gdańsk and in the Vistula delta, still accompanied by the two other species.
