The viperfish is one of the most unusual-looking fish in the deep sea. It is also one of the most popular and well-known species. It is one of the fiercest predators of the deep. This fearsome looking creature has a long dorsal spine that is tipped with a photophore, a light-producing organ. The viperfish uses this light organ to attract its prey through a process known as bioluminescence. By flashing the light on and off, it can be used like a fishing lure to attract smaller fish.
In spite of its ferocious appearance, the viperfish is a relatively small animal, growing to about 11 or 12 inches (30 centimeters) in length. They have a hinged skull, which can be rotated up for swallowing unusually large prey. They also have very large stomachs that allow them to stock up on food whenever it is plentiful. Viperfish are known to be preyed upon by sharks and some species of dolphin.