The first finding of the Ponto-Caspian mysid shrimp Hemimysis anomala G. O. Sars (Mysidae) in the Estonian coastal sea

The aim of this paper was to provide new data on the nektobenthic crustacean Hemimysis anomala in the Estonian coastal sea using trawling data on the density of mysid species. The non-native shrimp was found for the first time in the Estonian coastal sea in 2009. The species was found only once at the outer Pärnu Bay, the Gulf of Riga. The habitat where the species was found was characterized by coarse sand mixed with gravel, clay, and algal debris. The species was associated with the native mysid Neomysis integer. As the abundance of H. anomala was low, it is likely that the species does not affect the structure and functioning of phyto-and zooplankton communities or compete with fish fry for food.