''Asphinctites'' is an extinct genus of cephalopod belonging to the

Ammonite 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) ...

subclass.

References

Jurassic ammonites Fossils of Germany {{Ammonite-stub