Vampire squid

The vampire squid (Vampyroteuthis infernalis) is a deep-sea cephalopod with webbed arms and dark membranes. It is the sole living member of its order and is distinct from true squid and octopuses.

Marine snow: A continuous shower of organic particles and debris falling through the water column. The vampire squid gathers sinking particles as its main food source.
Cephalopod: A mollusk class that includes octopuses, squids, cuttlefish, and nautiluses. The vampire squid belongs to this class despite its unusual mix of traits.
Belemnitida: An extinct order of marine cephalopods with internal bullet-shaped shells. Vampyromorph relatives in the fossil record connect the group to ancient coleoids.
Deep-sea ecology: The study of organisms and ecological processes in the ocean’s deep regions. The vampire squid helps explain how animals persist where food and oxygen are scarce.
Cirrate octopus: A deep-sea octopus with paired fins and rows of fleshy cirri along its arms. Its similar deep-water adaptations invite comparison, though it is a true octopus.
Vampyromorphida: The cephalopod order containing the living vampire squid and its extinct relatives. This order places the animal apart from true squid and octopuses.
Muensterelloidea: An extinct group of Jurassic and Cretaceous vampyromorph cephalopods. These fossils document vampyromorph diversity long before the living species.
Marine snow food web: The ecological links formed by organisms that consume sinking organic particles in the ocean. Its particle-feeding connects surface production with deep-sea consumers.
Bioluminescence: The production and emission of light by living organisms. Light-producing organs help the squid startle predators and communicate in darkness.
Vampyroteuthis infernalis: The sole living species of vampire squid, a deep-sea cephalopod. This is the scientific species name for the animal described here.

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