The Bolitaeninae are a subfamily, in the family Amphitretidae, of small, common pelagic octopuses found in all tropical and temperate oceans of the world. The taxonomy of this taxon is not entirely certain; recent research suggests just two genera exist, Bolitaena and Japetella, both of which are thought to be monotypic by some authorities and under this view, the family would represent two very similar species: Bolitaena pygmaea and Japetella diaphana. However, currently a second species of Bolitaena, B. massyae is also recognised.
Vitreledonella richardi, also known as the glass octopus, is an incirrate octopus. It is in the genus Vitreledonella and of the family Amphitretidae.
Argonauta argo, also known as the greater argonaut, is a species of pelagic octopus belonging to the genus Argonauta. The Chinese name for this species translates as "white sea-horse's nest".
The blue-lined octopus is one of four species of highly venomous blue-ringed octopuses. It can be found in Pacific Ocean waters that stretch from Australia to Japan. It is most commonly found around intertidal rocky shores and coastal waters to a depth of 15 metres (49 ft) between southern Queensland and southern New South Wales. It is relatively small, with a mantle up to 45 millimetres (1.8 in) in length. In its relaxed state, it is a mottled yellow-brown with dark blue or black streaks covering the whole body apart from the underside of its arms, but its vibrant blue markings appear as a warning to predators when it feels threatened. Along with its other closely related species, the blue-lined octopus is regarded as one of the most dangerous animals in the sea, and its venom can be fatal to humans. This benthic octopus is one of four members of the genus Hapalochlaena, with the other species being the greater blue-ringed octopus, southern blue-ringed octopus, and the blue-ringed octopus. The blue-lined octopus is the only species of the four to display lined iridescent blue marking, as opposed to circular iridescent blue marking that the three other species tend to exhibit.
Opisthoteuthis californiana, also known as the flapjack octopus, or flapjack devilfish is a species of umbrella octopus.
Onykia ingens, the greater hooked squid, is a species of squid in the family Onychoteuthidae. It occurs worldwide in subantarctic oceans.
A. 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 27.6 mm (1.09 in) in mantle length (ML). The holotype is a mature male of 21.3 mm (0.84 in) ML. A live specimen of A. aldrichi has yet to be recorded.
Eledone 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.
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.
Eledone moschata, the musky octopus, is a species of octopus belonging to the family Octopodidae.
The curled octopus, also known as the horned octopus, lesser octopus or northern octopus, is a species of cephalopod found in the northeast Atlantic, ranging from Norway to the Mediterranean, including the British Isles. The total length of an adult is around 50 cm, but their arms are often tightly curled. It immobilises and eats large crustaceans by drilling a hole through their shell. It is mainly by-catch in commercial fisheries of the north eastern Atlantic and Mediterranean, where the common octopus is the preferred species.
Illex coindetii, commonly known as the southern shortfin squid or broadtail shortfin squid, is a species of neritic squids in the family Ommastrephidae. They are found in the Mediterranean Sea and on both sides of the north Atlantic Ocean.
Eledone massyae, the combed octopus, is a small benthic octopus found off the Atlantic coasts of southern South America, particularly Argentina and southern Brazil.
Eledone gaucha is a species of octopus from the southern Atlantic Ocean. It is a predator of fish, crabs, lobsters and molluscs.
Alloteuthis media, the midsize squid or little squid, is a species of squid in the family Loliginidae from the eastern Atlantic and the Mediterranean Sea. It is generally a by-catch species in trawl fisheries, although there is an active fishery in the western Mediterranean.
Gonatopsis borealis, the Boreopacific armhook squid, is a species of squid from the North Pacific Ocean. It is a member of the family Gonatidae. It is an abundant species which is currently caught mainly as a bycatch by fishing boats targeting other quarry. It is an important prey species for many commercially important species of fish, as well as for marine mammals.
Eucleoteuthis is a monotypic genus of squid from the family Ommastrephidae; the only species is Eucleoteuthis luminosa, the striped flying squid or luminous flying squid.
Opisthoteuthis agassizii is a lesser-known, deep-sea octopus first described in 1883 by Addison E. Verrill.
Opisthoteuthis bruuni is a species of finned cirrate octopus found along the western coast of South America. Their tissue is almost jelly-like, and they have short, round bodies.
Bathypolypus sponsalis, commonly called the globose octopus, is a deep sea cephalopod that can be found in both the eastern Atlantic Ocean and the Mediterranean Sea. It possesses many morphological traits adapted to a deep sea environment, including large eggs, reduced gills, no ink sac, and subgelatinous tissues. A distinguishing factor are the relatively large reproductive organs. Their diet consists of predominantly crustaceans and molluscs, but they sometimes consume fish as well. Bathypolypus sponsalis usually dies quickly after reproduction and only spawns once in their lifetime. Sexually mature females have a mantle length of at least 34 mm and sexually mature males have a mantle length of about 24 mm. Juveniles are white and transition to dark brown then to dark purple once maturity is reached.
