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
Sand goby rounded. In males, there is a conspicuous dark spot on the anterior dorsal fin and in both sexes there is a black patch on the caudal peduncle. The general colour is sandy brown with indistinct dark blotches and reticulations on the dorsal surface and dark striations on the pale fins. The colour of the male darkens during the breeding season and his fins become more coloured. The average size is about . The sand goby normally lives at greater depths than the common goby. It feeds on small invertebrates living on the seabed especially amphipods. It is well camouflaged and