Жылаңбас балықтар отбасысы

Family of ray finned fishes

Slickheads, also known as nakedheads or smoothheads, are deep water fishes that belong to the family Alepocephalidae. They are most commonly found in the bathypelagic layer, which is approximately 3000m below the surface. They get their name from the lack of scales on their heads. Similarly, the scientific name is from the Greek ᾰ̓ (a , "not"); λέπος (lepos, "scale"); and κεφαλή (kephalē, "head"). It has about 22 genera with ca. 96 species. The only known fossil genus is Carpathichthys from the Early Oligocene of Poland, although an undescribed species of Bathyprion and several indeterminate taxa are also known from the same formation. Fossil otoliths are also known, dating to the Early Eocene.

It’s been thought that as the Alepocephalidae age, they move down layers in the ocean, (mesopelagic waters and bathypelagic waters) due to mostly adolescent Alepocephalidae being reported near the surface, although there have been sightings of juveniles only several meters above the sea floor, which could suggest that some species may travel between different depths throughout their life stages, a vertical shift. Vertical shift could occur due to predation being higher close to the sea floor and/or warmer water having a larger abundance of plankton. Juvenile slickheads may have a preference to travel upwards to take advantage of the lack of predation and abundance of food to increase survival rates.

The species of Alepocephalidae are widely distributed throughout the world and can be found in the Atlantic, Indian, and western Pacific oceans, although they are difficult to find as they typically live around the bathypelagic layer of the ocean.