The vampire squid (Vampyroteuthis infernalis, lit. "vampire squid of Hell") is a small, deep-sea cephalopod found throughout the temperate and tropical oceans of the world. Unique retractile sensory filaments justify the vampire squid's placement in its own order: Vampyromorphida (formerly Vampyromorpha), which shares similarities with both squid and octopuses. As a phylogenetic relict it is the only known surviving member of its order, first described and originally classified as an octopus in 1903 by German teuthologist Carl Chun, but later assigned to a new order together with several extinct taxa.