Deep beneath the ocean, a terrifying predator lurks with teeth so large they can’t even fit inside its mouth: the fangtooth fish.

In proportion to body size, fangtooth fish have the largest teeth of any fish in the ocean, using them to effectively pierce and devour their prey. These animals are also the deepest living fish under the sea, preferring to inhabit depths down to 16,000 ft below the surface.

Image: Sandra Raredon/Smithsonian Institution

Thankfully, these beasts are harmless to humans, growing to a little over half a foot in length. Most deep sea creatures are very small, but have extremely large mouths full of teeth necessary for survival. Deep sea creatures cannot afford to pass up a potential meal, even if it’s much larger than they are.

Interestingly, fangtooth fish are so hardy that they can be brought to the surface and persist in an aquarium for several months at a time, despite being outside their natural habitat and conditions. This is very much unlike other deep sea fish, which often die instantly due to barotrauma from intense pressure changes.

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