Mnemiopsis

Mnemiopsis commonly known as comb jellies, that inhabit sea waters worldwide. They are notable for the groups of cilia they use for swimming. M. leidyi has become a member of the Norwegian fauna. It is a North American species, introduced in Norway through the ballast water of cargo ships trafficking the Norwegian coast.  Since 2005, when first observed has become common to see it in Southern Norway.  Climate change could enhance reproduction of Mnemiopsis in Norway.