what group of animals do octopus belong to
class Cephalopoda
title: Octopus text: Octopus The octopus is a soft-bodied, eight-limbed mollusc of the order Octopoda. Around 300 species are recognised, and the order is grouped within the class Cephalopoda with squids, cuttlefish, and nautiloids. Like other cephalopods, the octopus is bilaterally symmetric with two eyes and a beak, with its mouth at the center point of the eight limbs (traditionally called "arms", sometimes mistakenly called "tentacles"). The soft body can rapidly alter its shape, enabling octopuses to squeeze through small gaps. They trail their eight appendages behind them as they swim. The siphon is used both for respiration and for locomotion, by expelling title: Octopus text: of octopuses in extreme cases. Cephalopods have existed for 500 million years and octopus ancestors were in the Carboniferous seas 300 million years ago. The oldest known octopus fossil is "Pohlsepia", which lived 296 million years ago. Researchers have identified impressions of eight arms, two eyes, and possibly an ink sac. Octopuses are mostly soft tissue, and so fossils are relatively rare. Octopuses, squids and cuttlefish belong to the clade Coleoidea. They are known as "soft-bodied" cephalopods, lacking the external shell of most molluscs and other cephalopods like the Nautiloids and the extinct Ammonoidea. Octopuses have eight limbs like other title: Octopus text: ball, and to fill a glass by pouring water from a bottle. Octopus The octopus is a soft-bodied, eight-limbed mollusc of the order Octopoda. Around 300 species are recognised, and the order is grouped within the class Cephalopoda with squids, cuttlefish, and nautiloids. Like other cephalopods, the octopus is bilaterally symmetric with two eyes and a beak, with its mouth at the center point of the eight limbs (traditionally called "arms", sometimes mistakenly called "tentacles"). The soft body can rapidly alter its shape, enabling octopuses to squeeze through small gaps. They trail their eight appendages behind them as they swim. title: Octopus text: a jet of water. Octopuses have a complex nervous system and excellent sight, and are among the most intelligent and behaviourally diverse of all invertebrates. Octopuses inhabit various regions of the ocean, including coral reefs, pelagic waters, and the seabed; some live in the intertidal zone and others at abyssal depths. Most species grow fast, mature early and are short-lived. During breeding, the male uses a specially adapted arm to deliver a bundle of sperm directly into the female's mantle cavity, after which he becomes senescent and dies. The female deposits fertilised eggs in a den and cares for them title: Octopus text: "Haliphron atlanticus", weighed 61 kg (134 lb) and was estimated to have had a live mass of 75 kg (165 lb). The smallest species is "Octopus wolfi", which is around and weighs less than . The octopus is bilaterally symmetrical along its dorso-ventral axis; the head and foot are at one end of an elongated body and function as the anterior (front) of the animal. The head includes the mouth and brain. The foot has evolved into a set of flexible, prehensile appendages, known as "arms", that surround the mouth and are attached to each other near their base by