Black-faced blenny Black-faced blenny The black-faced blenny ("Tripterygion delaisi") is a small benthic fish from the family Tripterygiidae (triplefin-blennies). It occurs at depths of -3 to -40 m and lives on the substrate under large rocks, cliffs or other overhangs. Like all triplefin-blennies, "T. delaisi" has three dorsal fins and can hence easily be distinguished from members of the families Blenniidae (1 dorsal fin) and Gobiidae (2 dorsal fins) that have a similar live-style and general appearance. It has a peaked head and short tentacles above the eyes.⁠ The common name yellow black-faced blenny derives from the colouration of territorial males during
Round goby Nord-Ostsee (Kiel) Canal. As of 2010, the westernmost site of round goby occurrence in Europe was the Lower River Scheldt, the tidal zone in the river mouth, and Albert Canal, Belgium. In 2011, the round goby began invading the fresh waters of France: the species appeared in the Rhine River (on the border between France and Germany), and in the French part of the Moselle River. In total, 52 parasite species are registered in the round goby in the native area. Most abundant parasites of the Black-Sea round goby are metacercariae of trematodes of Heterophyidae family, such as "Cryptocotyle concavum",