Ammonites are the prehistoric of what family branch?

Ammonites are prehistoric marine mollusks that belong to the class Cephalopoda, which also includes modern squids, octopuses, and nautiluses. They are specifically part of the subclass Ammonoidea, characterized by their coiled and chambered shells. Ammonites thrived during the Mesozoic Era and became extinct around 66 million years ago during the Cretaceous-Paleogene extinction event. Their fossilized shells are important for dating and correlating the age of sedimentary rock layers.