First report of the non-native freshwater polychaete Namalycastis hawaiiensis (Johnson, 1903) (Nereididae: Namanereidinae) in Israel.
The subfamily Namanereidinae (Annelida: Nereididae), is one of the most successful polychaete groups to colonize brackish and freshwater environments worldwide. Among them Namalycastis hawaiiensis (Johnson, 1903) is one of the few that have been identified as invasive, including recent introduction to Japan and Australia via the aquarium trade. Here, we report for the first-time finding of an established population of N. hawaiiensis in a freshwater spring in Israel, well outside of its Indo-Pacific native distribution. We further report on the finding of specimens in a pet store and discuss its possible route of introduction via aquarium-trade.