(also Enhelyopus rockling)
- Other names: Fourbeard rockling
- Family: Hakes and burbots – Lotidae
- Similar species: burbot, rock gunnel, snake blenny, viviparous blenny
- Size: 20–30 cm.
- Appearance: A bottom-dwelling fish with an elongated body. Vent roughly half way along body, posterior to which the body is laterally compressed, accentuated by the long fringe of dorsal and ventral fins. First dorsal fin short and low, first ray long and prominent. Posterior dorsal very long. Caudal fin clearly separate, rounded. Pelvic fins well forward of pectorals. Four barbels: one on chin and three on snout. Skin slimy and scales difficult to see with the naked eye.
- Colouring: Back brown, belly silvery grey. Rear body may show irregular dark patches. Fins bluish, trailing edges of anal and caudal fins often darker.
- Reproduction: Spawns in deep water between February and August. Eggs float. Does not reproduce in Finnish waters.
- Food: Crustaceans and other benthic invertebrates.
- Distribution and habitat: The four-bearded rockling is a fish of the North Atlantic that has found its way into parts of the southern Baltic. Occurs only occasionally in Finnish waters. Lives at depths of 20 m down to 550 m.