Details: Gasropods are a group of marine and freshwater Mollusks. Their spiral shell is usually the only part preserved as a fossil. Gastropods first appeared 500 million years ago. Their evolution reached a peak in the Mesozoic era, and in the Cenozoic era they developed into forms very similar to today's specimens. They are useful paleo-ecologic indicators: what we know about their present life helps to reconstruct the environment in which they lived.
Gasropods are a group of marine and freshwater Mollusks.