Cymatoceras are nautiloids that lived from the Jurassic to the Oligocene. Its shell is made of two layers--the innermost being iridescent and the outer layer providing protection. The interior have partitions that divide the shell into compartments, which help the animal maintain buoyancy.
Species: Cymatoceras sakalavuz Class: Phylum Mollusca, Class Cephalopoda Subclass: Nautiloidea, Order Nautilida Family: Cymatoceratidae Age: Middle Cretaceous, Albian Stage (112 million years ago) Formation: Alpian Formation Locality: Mahajanga, Madagascar
