The hooked squid, family Onychoteuthidae, currently comprise about 20–25 species, in six or seven genera. They range in mature mantle length from 7 cm to a suggested length of 2 m for the largest member, Onykia robusta. The family is characterised by the presence of hooks only on the tentacular clubs, a simple, straight, funnel–mantle locking apparatus, and a 'step' inside the jaw angle of the lower beak. With the exception of the Arctic Ocean, the family is found worldwide.
Promachoteuthis is a genus of small, weakly muscled squid found at bathypelagic depths. Three species have been formally described, while another two await description.
Psychroteuthis 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 (1.44 ft).
Pyroteuthidae is a family of squids. The family comprises two genera. Species are diurnally mesopelagic, migrating into surface waters during the night. The family is characterised by the tentacles, which have a permanent constriction and bend near the base; and photophores occurring on the tentacles, eyeballs, and viscera. Members reach mantle lengths of 23–50 mm. Paralarvae of the family are common around the Hawaiian Islands, with up to 17% of collected specimens in the area belonging to Pyroteuthidae.
Thysanoteuthis is a genus of large squid comprising one well-known species, the diamond squid, and two dubious taxa.
Walvisteuthis, 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.
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.
Oegopsida is one of the two orders of squid in the superorder Decapodiformes, in the class Cephalopoda. Together with the Myopsina, it was formerly considered to be a suborder of the order Teuthida, in which case it was known as Oegopsina. This reclassification is due to Oegopsina and Myopsina not being demonstrated to form a clade.
Taoniinae is a subfamily containing ten genera of glass squids.
Ancistroteuthis lichtensteinii, also known as the angel clubhook squid or simply angel squid, is a species of squid in the family Onychoteuthidae and the sole member of the genus Ancistroteuthis. It grows to a mantle length of 30 cm. It lives in the western Mediterranean Sea, subtropical and tropical eastern Atlantic Ocean and western north Atlantic Ocean. Its diet include mesopelagic fish and pelagic crustaceans. It is sometimes taken as bycatch by commercial fisheries, but is not a targeted species.
Onychoteuthis banksii, the common clubhook squid, is a species of squid in the family Onychoteuthidae. It is the type species of the genus Onychoteuthis. This species was thought to have a worldwide distribution but with the revision of the genus Onychoteuthis in 2010, it is now accepted that Onychoteuthis banksii is restricted to the central and northern Atlantic and the Gulf of Mexico while a recently described species, Onychoteuthis horstkottei, is found in the Pacific Ocean. The type locality is the Gulf of Guinea.
Onykia carriboea, the tropical clubhook squid, is a squid in the family Onychoteuthidae, the type species of the genus Onykia. It is known with certainty only from immature specimens. The type locality of O. carriboea is the Gulf of Mexico. Onykia robsoni has been suggested as a junior synonym, owing to similarities between the species.
Filippovia knipovitchi, the smooth hooked squid, is a species of squid in the family Onychoteuthidae and the sole member of the genus Filippovia. It is found in the Antarctic and Atlantic Oceans, and reaches a mantle length of 35 cm.
Onychoteuthis is a genus of squid in the family Onychoteuthidae. The type species is Onychoteuthis bergii. While the genus is found worldwide in tropical and subtropical oceans, they can also occur in the North Pacific Ocean. There were previously considered to be four species in the genus but there are now considered to be roughly 10. These squid are frequently observed in the surface waters at night and they are often caught using dipnet at nightlight stations. The young squid are usually the only specimens captured using standard midwater trawls, the older squid are apparently able to avoid the trawls. They can, however be collected from the air as individuals are able to leap high out of the water, sometimes even landing on the deck of a ship.
Onykia is a genus of squids in the family Onychoteuthidae. Due to similarities between the genera, several recent authors consider the genus Moroteuthis a junior synonym of Onykia. The type species is Onykia carriboea, the tropical clubhook squid.
Notonykia africanae is a species of squid in the family Onychoteuthidae. It is the type species of the genus Notonykia. While the mature size of the species is unknown, it is known to reach a mantle length of at least 180 mm. Tentacles reach approximately 70% of the mantle length, and contain 14-20 club hooks. Arms are known to reach 27-45% and 33-55% of the mantle length; each containing 50-60 suckers. The species is located in southern waters off Australia, Tasmania, New Zealand and South Africa.
Nototodarus is a genus of squid. Example species in this genus include Nototodarus sloanii, a species sought for human food; in the process of harvesting N. sloanii Australian sea lions are frequently killed, since that marine mammal preys upon this squid species. Furthermore, New Zealand arrow squid, N. sloanii, is an important food source for the endangered yellow-eyed penguin, Megadyptes antipodes.
Todarodinae is a squid subfamily in the family Ommastrephidae.
Cephalopods exhibit various dermal structures on their mantles and other parts. These may take the form of conspicuous warts, cushions, papillae or scales, though in many species they are microscopic tubercles. The most elaborate forms are found among the oceanic squid of the order Teuthida.
Pterygioteuthis hoylei is a species of squid in the family Pyroteuthidae. It is considered conspecific with Pterygioteuthis giardi by some authorities. It can be identified from P. giardi by having four photophores on the tentacles and many chromatophores spread along the tentacle stalk and around the aboral surface of the tentacular club. It is also slightly larger than P. giardi, it has been so far recorded only from the eastern tropical Pacific Ocean where it is the only species of in the family Pyroteuthidae to occur there, although its actual distribution may be wider than currently known. The specific name honours the British malacologist William Evans Hoyle (1855-1926).
