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 invasive nematode "Anguillicoloides crassus". In the Vistula Lagoon, the most abundant parasites of the round goby are nematodes "Hysterothylacium aduncum" and "Anguillicoloides crassus". 25 species of parasites are noted in the round goby in the Great Lakes. The trematode "D. spathaceum" is most abundant core species overall. Also the cestode "Proteocephalus" sp. and the trematode "Neochasmus umbellus" are rather abundant. The round goby may circumvent more of the metacercariae of "N. umbellus" from completing their life cycle. The parasite “load” on the invasive gobies in the Great Lakes appears relatively low in comparison with their native habitats, lending support to