A cephalopod is any member of the molluscan class Cephalopoda such as a squid, octopus, cuttlefish, or nautilus. These exclusively marine animals are characterized by bilateral body symmetry, a prominent head, and a set of arms or tentacles modified from the primitive molluscan foot. Fishers sometimes call cephalopods "inkfish", referring to their common ability to squirt ink. The study of cephalopods is a branch of malacology known as teuthology.
Bobtail squid are a group of cephalopods closely related to cuttlefish. Bobtail squid tend to have a rounder mantle than cuttlefish and have no cuttlebone. They have eight suckered arms and two tentacles and are generally quite small.
Mark Douglas Norman is a scientist living in southern Australia. He works as a Chief Conservation Scientist with Parks Victoria.
Metasepia pfefferi, also known as the flamboyant cuttlefish, is a species of cuttlefish occurring in tropical Indo-Pacific waters off northern Australia, southern New Guinea, as well as numerous islands of the Philippines, Indonesia and Malaysia.
Cephalopods, which include squids and octopuses, vary enormously in size. The smallest are only about 1 centimetre (0.39 in) long and weigh less than 1 gram (0.035 oz) at maturity, while the largest—the giant and colossal squids—can exceed 10 metres (33 ft) in length and weigh close to half a tonne (1,100 lb), making them the largest living invertebrates. Living species range in mass more than three-billion-fold, or across nine orders of magnitude, from the lightest hatchlings to the heaviest adults. Certain cephalopod species are also noted for having individual body parts of exceptional size. The giant and colossal squids, for example, have the largest known eyes among living animals.
The pharaoh cuttlefish is a large cuttlefish species, growing to 42 cm in mantle length and 5 kg in weight. It is also known as seiche pharaon.
Euprymna stenodactyla is a species of bobtail squid.
Sepietta oweniana is a common marine mollusc from the order Sepiida, the cuttlefish.
Sepia mestus, also known as the reaper cuttlefish or red cuttlefish, is a species of cuttlefish native to the southwestern Pacific Ocean, specifically Escape Reef off Queensland to Murrays Beach off Jervis Bay. Reports of this species from China and Vietnam are now known to be misidentifications. S. mestus lives at a depth of between 0 and 22 m.
Sepietta petersi, also known as the mysterious bobtail, is a species of bobtail squid native to the Mediterranean Sea. A doubtful record of S. petersi also exists from the Atlantic Ocean off Morocco.
Rossia moelleri is a species of bobtail squid native to the northern Atlantic Ocean and the Arctic Ocean, eastward to the Laptev Sea and westward to Amundsen Bay. It occurs off western and northeastern Greenland, northeastern Canada, Labrador, Spitsbergen, Jan Mayen, and in the Kara Sea. R. moelleri lives at depths from 17 to 250 m.
Rossia mollicella is a species of bobtail squid native to the western Pacific Ocean, south from Sendai Bay, Japan. It occurs on the outer continental shelf and in the upper bathyal zone. R. mollicella lives at depths from 729 to 805 m.
Neorossia leptodons is a species of bobtail squid native to the southwestern Pacific Ocean, from New South Wales to South Australia. It lives at depths from 130 to 1,110 m.
All cephalopods possess flexible limbs extending from their heads and surrounding their beaks. These appendages, which function as muscular hydrostats, have been variously termed arms, legs or tentacles.
Cephalopod ink is a dark-coloured or luminous ink released into water by most species of cephalopod, usually as an escape mechanism. All cephalopods, with the exception of the Nautilidae and the Cirrina, are able to release ink to confuse predators.
Cuttlefish or cuttles are marine molluscs of the order Sepiida. They belong to the class Cephalopoda which also includes squid, octopuses, and nautiluses. Cuttlefish have a unique internal shell, the cuttlebone, which is used for control of buoyancy.
Peripatopsidae is one of the two living velvet worm families.
All extant cephalopods have a two-part beak, or rostrum, situated in the buccal mass and surrounded by the muscular head appendages. The dorsal (upper) mandible fits into the ventral (lower) mandible and together they function in a scissor-like fashion. The beak may also be referred to as the mandibles or jaws.
Louise Allcock is a British researcher, best known for her work on ecology and evolution of the cephalopods of the Southern Ocean and deep sea. She is the editor of the Zoological Journal of the Linnean Society.
Octopus australis is a species of octopus. It gets the common name hammer octopus from a modified arm possessed by males and used in reproduction. It was first described by William Evans Hoyle in 1885, based on a specimen found in Port Jackson in New South Wales.
