Ammonoidea
Ammonite/mollusk

 

ammonite

Fossil Sizes:
Diameter from one side of coil to the other: 1 inch to 6 feet
Diet: Carnivore (ate tiny invertebrates)
Habitat: Aquatic
When: 408-66 Million Years Ago (living relative: Chambered Nautilus)
Skeletal Features: There were plenty of these tentacled creatures floating along in the seas of the Cretaceous! Although they came in many shapes and sizes, most lived in shells that were coiled. The Ammonite lived right inside the opening, leaving the rest of the shell hollow. Some might have been bottom-dwellers, while others might have used gases in the empty parts of their shells to float.

© 1999 Carnegie Museum of Natural History