Deepest Fish - Snailfish
Pseudoliparis amblystomopsis

Because the fish live in complete darkness, they use vibration receptors on their snouts to navigate the ocean depths and to locate food. Their eyes appear to be virtually nonexistent. Eyes in most organisms are designed for gathering light in the creature's visual field and transmitting it to the brain - giving it useful information about its environment. In a world where no sunlight ever penetrates there's probably little use for eyes. The researchers on this project have said they expect to find fish living even deeper than these!

The Hadeep project, which began in 2007, is a collaboration between the University of Aberdeen's Oceanlab and the University of Tokyo's Ocean Research Institute and aims to expand our knowledge of biology in the deepest depths of the ocean. The researchers have been looking at the Hadal zone - the area of ocean that sits between 6,000 and 11,000m (20,000-36,000ft). It consists of very narrow trench systems, most of which are found around the Pacific Rim.