Laevaptychus latus

Aptychus are pieces that are isolated or in pairs, of chitinous or calcareous composition and are part of the chewing apparatus, contributing to the grinding of food. Most pre-Jurassic ammonites had beak-shaped jaws, similar to those of modern cephalopods. The beak can bite and tear large pieces of tissue, which are then carried to the oral cavity, to later be ingested.