Reconsidering evidence for Mnemiopsis invasion in European waters: reply

Abstract

In their comment, Gorokhova and Lehtiniemi (Gorokhova and Lehtiniemi, 2010) raise doubts about the accuracy of the taxonomic identification of Mnemiopsis leidyi which has recently invaded the Baltic Sea. They question the conclusions of Javidpour et al. (Javidpour et al., 2009) that the observed feeding of adult M. leidyi on tentaculate ctenophore larvae indicates cannibalism, because the prey might also be larvae of other ctenophore species. We agree that morphotaxonomic distinction of M. leidyi-larvae from some other ctenophores species is difficult and molecular assays should be considered as a helpful tool besides taxonomic keys. The importance of molecular evidence has recently been emphasized for wider plankton studies by McManus and Katz (McManus and Katz, 2009). When we first observed the occurrence of M. leidyi in the Baltic Sea, we confirmed the morphological taxonomic identification by …