A recently discovered large predatory fish found in deep water off the coast of Japan is a reminder that we know more about the surface of the Moon or Mars than we do about the deep oceans.

In 2016, marine biologists brought up a strange, large fish from 8,000 feet below the surface in Suruga Bay, on the Pacific coast of Honshū in Shizuoka Prefecture, Japan. The fish was over a meter long and weighed 25 kg. Subsequently, three more fish of the same type were also caught. While large bony fish are not uncommon in shallow water, they are relatively rare in the deep ocean. 

In a recent paper in the journal Nature, the new species is described as a “colossal slickhead.”  Slickheads are a family, Alepocephalidae, of deep-water fishes, most common below 1,000 meters (3,300 ft). They get their name from the lack of scales on the head. The newly discovered species is much larger than any other known slick head. Also unlike others of the Alepocephalidae family that eat primarily gelatinous zooplankton, the new species has rows of sharp teeth and preys on other fish. Scientists believe that the colossal slickhead is a top predator in the deepwater environment of the bay.

In recognition of its size, the new species has been named Yokozuna Iwashi. Yokozuna is the highest-ranking among Sumo wrestlers.

Scientists estimate that 91 percent of ocean species have yet to be classified and that more than eighty percent of our ocean is unmapped, unobserved, and unexplored.

Colossal deep sea fish named after Yokozuna