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Cephalopods

The cephalopods are a class of molluscs. Members include octopuses, squids, cuttlefish, nautiluses and the fossil ammonites. They are characterised by a ring of tentacles around their mouth, and swim using a form of jet propulsion by squirting water out of their body. All cephalopods are carnivorous.

Scientific name: Cephalopoda

Rank: Class

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Prehistoric life

All Prehistoric Cephalopods

Fossil types

Learn more about the other animals and plants that also form these fossils.

Exceptional preservation Exceptional preservation
Normally, only the hard parts of animals and plants - shell, bone, teeth and wood - are preserved as fossils. However, every now and then conditions permit the preservation of soft parts and create treasure houses of information for palaeontologists.

About

A cephalopod is any member of the molluscan class Cephalopoda (Greek plural Κεφαλόποδα (kephalópoda); "head-feet"). These exclusively marine animals are characterized by bilateral body symmetry, a prominent head, and a set of arms or tentacles (muscular hydrostats) modified from the primitive molluscan foot. Fishermen sometimes call them inkfish, referring to their common ability to squirt ink. The study of cephalopods is a branch of malacology known as teuthology.

Cephalopods became dominant during the Ordovician period, represented by primitive nautiloids. The class now contains two, only distantly related, extant subclasses: Coleoidea, which includes octopuses, squid, and cuttlefish; and Nautiloidea, represented by Nautilus and Allonautilus. In the Coleoidea, the molluscan shell has been internalized or is absent, whereas in the Nautiloidea, the external shell remains. About 800 living species of cephalopods have been identified. Two important extinct taxa are the Ammonoidea (ammonites) and Belemnoidea (belemnites).

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Classification

  1. Life
  2. Animals
  3. Molluscs
  4. Cephalopods

BBC News about Cephalopods

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