The name "Vampire Squid" name is a misnomer because the animal is certainly NOT a vampire, nor a squid. This unique cephalopod is more closely related to octopuses than to squids. It is about the size of a football and has eight arms (like an octopus), but lacks the feeding tentacles/suckers (as present on squids). It might be an octopus, but even that is very doubtful. Most likely it is a different type of cephalopod (albeit a deep-water one), and a new name would be fitting for this unique cephalopod.
Unlike other cephalopods, the “vampire squid” is not a carnivore; instead it is a generalist that feeds on “falling” debris in the ocean depths. The “vampire squid” also lacks an ink sack. The “vampire squid” is the only cephalopod that does not actively track its prey. Also, unlike other cephalopods, the “vampire squid” does not die after laying its eggs.
“Vampire squids” can also emit bioluminescent, sticky mucus that glows for up to 10 minutes, thereby allowing the animal it to escape a predator. Usually, “vampire squids” float peacefully in their deep, oxygen-deprived environment-awaiting for food to float to them as floating debris. The “vampire squid” can swim away (it uses jet propulsion to avoid predators, but its speed is short lived.
This unique cephalopod lives as a floater and a generally weak swimmers (although when under attack, they can move as fast as two body lengths/second). It lives in deep, dark frigid ocean waters, at bathyal depths between 2,000 and 3,000 feet (609-914 m) deep, “where the sun doesn’t shine,” and the water temperature is 4-6 degrees Celcius.
Figure 1. A typical red-colored adult of the so-called “vampire squid.” These animals drift with the deep-ocean currents and eats food that has fallen from the overlying shallow tropical and temperate waters above.
Adult “vampire squids” are about 30 cm (1 foot) long and have eight long “arms” (without sucker disks) and with a pair of large eyes for optimal vision in dim waters. They essentially have permanent night vision. Relative to the size of the adult animal, “vampire squids” have some of the largest (if not the largest) eyes in the animal kingdom. Also, the eyes of “vampire squids” are blue.
The “vampire squids” live up to 10 years = much longer than other cephalopods. [Note: most octopus live for 1-5 years, and the Nautilus cephalopod can live for 20+ years. They lack an ink sac. They don’t hunt for food; it comes to them.
Figure 2. The individual shown is this figure has its “cape” turned inside out, like an umbrella. This happens most likely when the animal is disturbed and wants to confuse predators. If necessary, “vampire squids” can reshape their bodies into spiny (spiky) balls.
Juvenile “vampire squids” are black or blackish and have a second pair of fins closer to the arms. As these juveniles grow bigger, their additional fins are absorbed back into the body. Also, the “vampire squid” can regrow the tips of their arms. Furthermore, they also have a “little glow stick”on their arms in order to confuse predators in the dark, inky depths. The “vampire squid” can glow in the dark for up to 10 minutes.
Figure 3. A juvenile “vampire squid.”
FOSSIL RECORD
The earliest record is of early middle Jurassic age (201-174 million years old). Their anatomy has hardly changed since then (i.e., there has been no reason to change).
CLASSIFICATION
Phylum Mollusca
Class Cephalopoda
Order Vampyromorphia = probably ancestral for both octopuses and squids.
Family Vampyroteuthidae
Genus Vanpyroteuthis [literally means “vampire squid from hell = an undeserved name!]
Type Species V. infernails [this is the only known species of this genus]
REFERENCES
Monterey Bay Aquarium Research Institute (MBARI) = excellent videos of these so-called “squids.”
National Geographic website
Wikipedia
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