 Ammonoidea

Ammonoids are a group of extinct marine mollusc animals in the subclass Ammonoidea of the class Cephalopoda.These molluscs, commonly referred to as ammonites, are more closely related to living coleoids (i.e., octopuses, squid, and cuttlefish) than they are to shelled nautiloids such as the living "Nautilus" species.