Wikipedia
Black swallower
The black swallower, Chiasmodon niger, is a species of deep sea fish in the family Chiasmodontidae. It is known for its ability to swallow fish larger than itself.
It has a worldwide distribution in tropical and subtropical waters, in the mesopelagic and bathypelagic zones at a depth of . It is a very common and widespread ocean fish; of its genus, it is the most common species in the North Atlantic.