A Relic in the Oxygen-Starved Depths
The scientific name Vampyroteuthis infernalis translates to "vampire squid from hell," a name inspired by its velvety black-to-red skin, cloak-like webbing, and eyes that can appear red or blue. German naturalist Carl Chun coined the name in 1903. This animal is not a true squid or octopus but the last surviving member of its own order, Vampyromorphida, making it a phylogenetic relict. It resides in the oxygen minimum zone (OMZ) of temperate and tropical oceans, typically at depths of 600 to 1,200 meters where oxygen saturation can be as low as 3%. The water temperature here is a cold 2 to 6 degrees Celsius.
Reaching a maximum length of about 30 cm, its body is gelatinous and neutrally buoyant, allowing it to drift effortlessly. A distinct feature is its eyes, which are proportionally the largest of any animal in the kingdom, measuring up to 2.5 cm in diameter. Unlike other cephalopods, it doesn't hunt live prey. Instead, it is a detritivore, feeding on "marine snow"—a mix of sinking organic material like dead plankton, fecal pellets, and mucus.
A Life of Extreme Energy Conservation
To survive in the OMZ, the vampire squid has the lowest mass-specific metabolic rate of any known cephalopod. Its blood contains high-affinity hemocyanin, a copper-based protein that is exceptionally efficient at binding and transporting oxygen, which it absorbs through large gills. This slow-paced life extends to its reproduction. Females reproduce multiple times, a strategy different from most cephalopods which have a single, high-energy reproductive event before death. A female may spawn more than 20 times in her life. One studied female had already released an estimated 3,800 eggs and still held 6,500 more for future spawning.
For defense, it lacks the ink sacs of its relatives. If threatened, it pulls its webbed arms up and over its body into a "pineapple posture," covering its head and exposing fleshy, spine-like projections called cirri. It can also eject a sticky cloud of bioluminescent mucus from its arm tips. This glowing barrage can last for nearly 10 minutes, dazzling a predator while the squid escapes into the darkness. The entire body is covered in light-producing organs called photophores, which it can flash to disorient attackers.