The Western Tubenose Goby (Proterorhinus semilunaris) is part of the P. marmoratus species complex, native to the Aegean and Ponto-Caspian basins. Proterorhinus semilunaris is native to freshwaters of the Black Sea and Aegean basins (Stepian and Neislon 2013; Froese and Pauly 2021).. It has been introduced to the Vistula River basin (Froese and Pauly 2021).The western tubenose goby (Proterorhinus semilunaris Heckel, 1837) is expanding its range into the St. Lawrence River:, reaching Quebec by 2023 (Goldsmit et al. 2023). However,it has not yet reached tidal waters.