Monotypic cephalopod genera

Spirula spirula is a species of deep-water squid-like cephalopod mollusk. It is the only extant member of the genus Spirula, the family Spirulidae, and the order Spirulida. Because of the shape of its internal shell, it is commonly known as the '''ram's horn squid or the little post horn squid. Because the live animal has a light-emitting organ, it is also sometimes known as the tail-light squid'''.

Velodona togata is a species of octopus in the monotypic genus Velodona. First described by Carl Chun in 1915, with a second subspecies discovered by Guy Coburn Robson in 1924, it was named for the distinctive membranes on its arms.

Heterololigo is a monotypic genus of squids containing the single species Heterololigo bleekeri. It was formerly classified in the genus Loligo; some authors still include it there, but DNA evidence supports its separation into a genus of its own. This species is known by the common name spear squid, or yari-ika in Japanese.

Lampadioteuthis megaleia is a small, colorful squid, the only species in the only genus in the monotypic family Lampadioteuthidae. It is sometimes known as the wonderful firefly squid. It was formerly classified in the family Lycoteuthidae, but differs from them mainly by having a hectocotylus in the males and by the possession of a rostrum on the gladius.

Vulcanoctopus hydrothermalis, also known as the vent octopus, is a small benthic octopus endemic to hydrothermal vents. It is the only photographed species of the genus Vulcanoctopus. Other species such as Vulcanoctopus tangaroa and Vulcanoctopus tegginmathae have been accepted but are near undocumented. This vent octopus is endemic to the hydrothermal vent habitat that is located in the East Pacific Rise.

Australiteuthis aldrichi is a small species of squid found in northern Australian waters. The species was described by Chung Cheng Lu in 2005 based on specimens collected in the inshore waters of Northern Australia. The largest known individual of this species is a mature female measuring in mantle length (ML). The holotype is a mature male of ML. A live specimen of A. aldrichi has yet to be recorded.

Parateuthis tunicata, the only known member of the genus Parateuthis, is the scientific name currently given to a species of squid based on a single specimen. The validity of Parateuthis and of P. tunicata is uncertain. The sole specimen was found in the Antarctic Ocean, and is held in the repository at the Museum für Naturkunde in Berlin, Germany.

Grimalditeuthis bonplandi is a squid named after the Grimaldi family, reigning house of Monaco. Prince Albert I of Monaco was an amateur teuthologist who pioneered the study of deep sea squids by collecting the 'precious regurgitations' of sperm whales. The specific name bonplandi refers to the French scientist Aimé Bonpland.

Bathypurpurata is a genus of incirrate octopus in the family Megaleledonidae from the Antarctic Ocean. The genus has only one species, Bathypurpurata profunda, a small purple octopus which lacks an ink sac and has a single row of suckers and a very large salivary gland. It was described in 2005 from a type specimen caught between the Antarctic Peninsula and the South Shetland Islands.

Ancistrocheirus lesueurii, the sharpear enope squid, is the only species in the genus Ancistrocheirus and family Ancistrocheiridae. With a mantle length of , this moderately sized squid may be found throughout the tropical and subtropical oceans. They tend to be found at mesopelagic depths ( down).

Nectoteuthis pourtalesi is a bathybenthic species of bobtail squid native to the tropical western Atlantic Ocean, specifically Florida and the Antilles.