The Shrimp Palaemon macrodactylus Is a New Species of the Western Sea of Azov Fauna in the Waters of Elevated Salinity

The shrimp Palaemon macrodactylus have been seen for the first time in the estuaries of the western Sea of Azov (Sivash Bay, Molochny Estuary) characterized by water with increased salinity (≥30‰). The caught shrimp were females with a total body length ranging from 39.9 to 61.0 mm. They were described morphologically; their biological features were also given, in particular, maturity of gonads and nutrition specificities. The possible ways of invasion and vectors of subsequent spread of Palaemon macrodactylus in the Sea of Azov were traced. The potential place of this species in the ecosystem of the Sea of Azov is discussed.