WThe seven-arm octopus is one of the two largest known species of octopus; based on scientific records, it has a maximum estimated total length of 3.5 m (11 ft) and mass of 75 kg (165 lb). The only other similarly large extant species is the giant Pacific octopus, Enteroctopus dofleini.
WAncistrocheirus lesueurii, the sharpear enope squid, is the only species in the genus Ancistrocheirus and family Ancistrocheiridae. With a mantle length of 25 cm, this moderately sized squid may be found throughout the tropical and subtropical oceans. They tend to be found at mesopelagic depths.
WThe giant squid is a species of deep-ocean dwelling squid in the family Architeuthidae. It can grow to a tremendous size, offering an example of deep-sea gigantism: recent estimates put the maximum size at around 12–13 m (39–43 ft) for females and 10 m (33 ft) for males, from the posterior fins to the tip of the two long tentacles. The mantle of the giant squid is about 2 m long, and the length of the squid excluding its tentacles rarely exceeds 5 m (16 ft). Claims of specimens measuring 20 m (66 ft) or more have not been scientifically documented.
WAturia is an extinct genus of Paleocene to Miocene nautilids within Aturiidae, a monotypic family, established by Campman in 1857 for Aturia Bronn, 1838, and is included in the superfamily Nautilaceae in Kümmel 1964.
WBathypolypus is a genus of octopuses in the monotypic family Bathypolypodidae. It has five described species.
WBathyteuthis is the singular genus of squid in the family Bathyteuthidae, encompassing three species. None has a mantle length greater than 80 mm.
WChtenopteryx is a genus of small, muscular, midwater squid in the monotypic family Chtenopterygidae. Four species are presently recognized in the genus, but more are believed to exist.
WEledone is a genus of octopuses forming the only genus in the family Eledonidae. It is mainly distributed in the northern and southern Atlantic Ocean, with one species, E. palari, described from the southwestern Pacific Ocean and eastern Indian Ocean in waters around Indonesia and Australia and another, E. microsicya, from the western Indian Ocean. One species, E. thysanophora, is now regarded as a synonym of the brush-tipped octopus.
WJoubiniteuthis portieri, also known as Joubin's squid from the monotypic family Joubiniteuthidae and genus Joubiniteuthis. It is a rare, small squid which occurs in the mesopelagic to bathypelagic zones and which has a worldwide distribution in tropical and subtropical regions. It is a distinctive squid having long arms I-III which have numerous small suckers in six rows. Its biology is little known and it is thought that it stays in the depths of the ocean with its arms outstretched waiting for small animals to ensnare after they have accidentally swum into the arms. This species is named after Louis Joubin, a French zoologist. It is known to reach a mantle length of 9 cm.
WLepidoteuthis grimaldii, also known as the Grimaldi scaled squid, is a large squid growing to 1 m in mantle length. It is 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 Grimaldi scaled squid was first collected from the stomach contents of a sperm whale. It is a widely distributed species in tropical and subtropical areas of the North and South Atlantic, the southern Indian Ocean and the Pacific Ocean, where it has been recorded off Japan and in the west Pacific.
WBigfin squids are a group of rarely seen cephalopods with a distinctive morphology. They are placed in the genus Magnapinna and family Magnapinnidae. Although the family is known only from larval, paralarval, and juvenile specimens, some authorities believe adult specimens have also been seen. Several videos have been taken of animals nicknamed the "long-arm squid", which appear to have a similar morphology. Since none of the seemingly adult specimens has ever been captured or sampled, it remains uncertain if they are of the same genus or only distant relatives.
WPholidoteuthis is a genus of squid in the monotypic family Pholidoteuthidae, comprising at least two species. The defunct genus Tetronychoteuthis was previously incorporated into Pholidoteuthidae based upon a singular taxon known as Tetronychoteuthis massyae. Following the discovery of Pholidoteuthis boschmai in 1950, T. massaye was placed into Pholidoteuthis, with Tetronoychoteuthis considered a nomen dubium. P. boschmai is now considered a junior synonym of P. massyae.
WPromachoteuthis is a genus of small, weakly muscled squid found at bathypelagic depths. Three species have been formally described, while another two await description.
WPsychroteuthis glacialis, the glacial squid, is the only known species in the monotypic genus Psychroteuthis, in the family Psychroteuthidae. While only one species has been confirmed, two undescribed species also probably exist. The species occurs in coastal waters near Antarctica and South America. It grows to a mantle length of 44 cm.
WSpirula 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.
WStauroteuthis is a genus of deepwater octopus, a cephalopod mollusk. This is the only genus in the family Stauroteuthidae, and only two species have been described in this genus.
WThysanoteuthis is a genus of large squid comprising one well-known species, the diamond squid, and two dubious taxa.
WTremoctopus is a genus of pelagic cephalopods, containing four species that occupy surface to mid-waters in subtropical and tropical oceans. They are commonly known as blanket octopuses, in reference to the long, transparent webs that connect the dorsal and dorsolateral arms of the adult females. The other arms are much shorter and lack webbing.
WWalvisteuthis, the stubby hook squids, is a genus of squid in the family Onychoteuthidae. The genus contains four species. They are characterised by possessing oval fins which are not drawn-out posteriorly, the gladius has elongated-rhomboid vanes and a short, blunt rostrum which is perpendicular to tip of gladius, the gladius is visible beneath skin at the dorsal midline and they only have primary occipital folds.