4SEAS

Deep seas are inhabited by very small number of fishes. At present only 7 species of fish: three species of cusk eels (Ophidiidae) and four species of snailfishes (Liparidae) were found in the deep trenches. The deepest caught fishes were Abyssobrotula caught in the Puerto Rico Trench at the depth 8370 m and Hadal snailfish Pseudoliparis amblystomopsis caught at 7800 meters depth. Startling is the appearance of the deep-sea fishes: most of them have slim, jelly-like body, which are luminous bodies.

In the darkness of the deep waters the ability to glow is of great importance. Predatory fish are attracted glowing lure prey. At their potential victims, on the contrary, many shimmering photophores can disorient predators. Some fish glows only the lower part of the body, which makes them less visible against the background of scattered skylight. But the main task of photophores - this, of course, the designation of individuals of one species. Many of these fish have a very complex telescopic eye, a batilihnopsa (born Javelin spoockfish, Lat. Bathylychnops exilis) 2 pairs of them! In gigantury (English, Latin. Gigantura) telescopic eye kept on stems, allowing it to take a very weak light sources, such as other luminous fish. Eyes of some fish, such as fish-haunted (born Brownsnout spookfish, Lat. Dolichopteryx longipes) is used to focus the lens and a system of thousands of tiny mirrors. At very great depths (more than 2-3 km), where the light does not penetrate, the vision ceases to play an important role, and here there are totally blind fish with atrophied eyes, for example tiflonus (Eng, Lat. Typhlonus), angler (born Anglerfish) laziognatus (Eng, Lat. Lasiognathus)).