The Vampire Squid Doesn't Drink Blood and Isn't a Squid

illustration of three vampire squid — Photographs of vampire squid are extremely rare, due to the extreme depths they call home. BlueRingMedia / Shutterstock

The vampire squid (Vampyroteuthis infernalis) isn't actually a squid. And though its scientific name means "vampire squid from hell," it isn't actually a vampire either. Although, in the deep ocean where vampire squids live, it's always pretty dark.

Like octopuses, cuttlefish and other squid, the vampire squid is a cephalopod. Cephalopods are marine animals characterized by bilateral body symmetry, a prominent head and a set of arms or tentacles.

But the vampire squid has a taxonomic order of its own. That's because it shares traits with both squid and octopuses, and yet is neither an octopus nor a squid.

What Do Vampire Squid Look Like?

The vampire squid, which can grow to about 1 foot (30 centimeters) in length and 6 inches (15 centimeters) in width, can look black or a pale reddish hue.

They have giant clear eyes that are the largest in proportion to its body size of any living animal. The eyes sometimes look blue or red, but that's because they're reflecting off the ocean water, light or other organisms.

They also have eight arms that are connected by webbing and fins on the sides and adorned with tiny spines.

Vampire Squid Defense Mechanisms

Though these crimson, caped misfits look threatening with their dark, spiny underbellies, they're not hunters and have very few defenses. The vampire squid inverts its webbed arms into a squishy, black, spiny ball like a pair of socks — or it sprays junk at its would-be predators.

Cephalopods living in shallower water protect themselves with jets of dark ink, but since vampire squid already live in the dark, they squirt out a colorless, bioluminescent fluid to confuse potential predators.

Vampire squid also have little lights called photophores (light-producing organs) at the end of their eight long, suction-less arms and two white spots on their head that act as photoreceptors.

Where Do Vampire Squid Live?

The ocean, like the atmosphere, has strata. Vampire squid live in the mesopelagic zone of the open ocean, which starts where the sunny, productive epipelagic zone at the surface ends, down at around 660 feet (200 meters).

It extends to the mesopelagic's dim, deep "twilight zone" that extends to around 3,280 feet (1,000 meters) below the surface.

There's almost no oxygen at these depths, which is why it's called the oxygen minimum zone (OMZ) or oxygen minimum layer. Deep sea organisms that live this far down have adapted to survive with minimal oxygen.

What Do Vampire Squid Eat?

Vampire squids are the only living cephalopods that don't eat live prey. They are detritivores, meaning that they eat dead, organic materials in the deep sea that fall down from above.

Their diet consists of marine snow, a combination of dead animals, rotting materials, feces and snot. They eat dead plants, gelatinous zooplankton, abandoned larvae houses, crustacean molts and dead diatoms.

They use their feeding tentacles, aka filaments — thin, tentacle-like appendages — to trap marine snow and small organisms for their meals.