coleoid
Coleoid is a subclass of cephalopods within the phylum Mollusca, comprising octopuses, squids, and cuttlefish, along with several extinct groups such as belemnites. It is contrasted with the nautiloids, which retain external shells.
Living coleoids are characterized by the loss of an external shell. Most have an internal shell or
Coleoids are carnivorous and occupy a wide range of marine habitats, from shallow coastal waters to the
Fossil coleoids include belemnites and other extinct groups; the living coleoids comprise the octopuses, squids, and