Cephalopod of the Day: The Vampire Squid

As a phylogenetic relict, it is the only known survivor of its order, Vampyromorphida. Its eight legs are connected by webbing, while its two long retractile filaments distinguish it from its 8 legged cousins.

Shown in the video is a threat response called the "pumpkin" or "pineapple" posture, wherein the vampire squid inverts its caped arms back over the body, presenting an ostensibly larger form covered in fearsome-looking, though harmless, spines (called cirri).

The vampire squid is an extreme example of a deep sea cephalopod, thought to reside at aphotic (lightless) depths from 600 to 900 metres (2,000 to 3,000 ft) or more. Within this region of the world's oceans is a discrete habitat known as the oxygen minimum zone (OMZ).

To cope with life in the (literally) suffocating depths, vampire squids have developed several interesting adaptations. Of all deep-sea cephalopods, their mass-specific metabolic rate is the lowest.

These animals have weak musculature, but maintain agility and buoyancy with little effort because of sophisticated statocysts (balancing organs akin to a human's inner ear) and ammonium-rich gelatinous tissues closely matching the density of the surrounding seawater.

Here is what fascinated me the most and made me decide to share this little guy with all of you.
Like many deep-sea cephalopods, the vampire squid lacks ink sacs.
If disturbed, it will curl its arms up outwards and wrap them around its body, the "pineapple" shown in the video.

If highly agitated, it may eject a sticky cloud of bioluminescent mucus containing innumerable orbs of blue light from the arm tips. This luminous barrage, which may last nearly 10 minutes, would presumably serve to dazzle would-be predators and allow the vampire squid to

disappear into the blackness without the need to swim far. The glowing ink is also able to stick to the predator, creating what is called a burglar alarm (making the vampire squid's predator more visible to secondary predators).

The display is made only if the animal is very agitated because regenerating the mucus is metabolically costly. The vampire squid also has bioluminescent organs at the end of all of its arms, using them as a sort of lure to attract some prey.