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Vampyroteuthis infernalis [vam pI rO too' this in fer nah' lis]
The vampire squid is named for its jet-black skin (which can appear red or purple under certain light conditions), the cape-like webbing between its arms, and eyes that appear red under most light conditions (they look blue when seen from a submersible, however). Those eyes are proportionally larger than those of any other animal in the world; a squid six inches long will have eyes that are an inch across, which are comparable to the eye size of a full-grown dog.
The vampire squid has eight long arms and two retractable filaments that can extend well past the total length of the animal. Each arm is lined with rows of fleshy spines. Only the distal half (farthest from the body) of the arms have suckers.
The vampire squid is almost entirely covered in light-producing organs called photophores, which are larger and more complex at the tips of the arms and at the base of the two fins, but are absent from the undersides of the caped arms. These photoreceptors produce luminescent clouds of glowing particles that allow the vampire squid to glow. Like its cousin the octopus, the vampire squid has pigment organs called chromatophores. Unlike those of the octopus, however, those of the vampire squid are poorly developed, meaning that the vampire squid cannot change its skin color at will like the octopus can. The vampire squid also lacks the ink sac found in many other cephalopods.
Maximum length is 12 inches, with a diameter roughly the same as that of a football. Females are larger than males.
Distribution and Habitat
Vampire squid are found in all oceans between latitudes 40 degrees north and 40 degrees south. A true deep sea cephalopod, the vampire squid spends its entire life at a depth of 4,900 to 8,200 feet, where there is virtually no light, very little oxygen, and the temperature rarely exceeds 43 degrees Fahrenheit.
The vampire squid is carnivorous, but is not an aggressive hunter. While drifting, the squid deploys one filament at a time until one of them contacts an animal of prey. The squid then swims around in a circle hoping to catch the prey, such as small shrimps, by surrounding them with the webbing between its arms. Once the victim is trapped, it is pushed inside towards the mouth.
It is most likely that males transfer spermatophores to the female from their funnel. The female then discharges the fertilized eggs directly into the water. Mature eggs are about 1/10 inch in diameter and are found free-floating in small masses.
Another unique aspect of the biology of the vampire squid is the dramatic metamorphosis that results in changes in the size, shape and position of the fins. At about 1/2- to 1-inch mantle length, juveniles begin to grow a second set of fins located more anteriorly (toward the arms) than the first pair. Once the new pair reaches a functional size, the original pair is reabsorbed. This transition reflects a change in swimming style from jet propulsion as juveniles to aquatic "flight" using fins as adults.
A vampire squid can swim surprisingly fast by using its fins to fly through the water, covering up to two body lengths per second, and can accelerate to such speed in five seconds. It cannot maintain this speed for long, however.
When threatened, the vampire squid makes an erratic escape by quickly moving the fins toward the funnel, followed by a jet from the mantle as it zig-zags through the water. The squid's defensive posture occurs when the arms and web are spread over the head and mantle. This position of the arms and web makes the squid more difficult to injure because of the protection provided to the head and mantle, and also because this position exposes the heavy black pigmented regions on the animal which make it difficult to identify in the dark depths of the ocean.
The vampire squid's principal escape response involves the glowing of the light organs on the tip of the arms and at the base of the fins. This glowing is followed by a flailing of the arms which makes it very difficult to determine exactly where the squid is in the water. The squid then ejects a luminescent mucous cloud. When the light show has ended, it is practically impossible to tell whether the squid has glided away or has simply blended into the dark water.
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This page was last updated on August 26, 2018.