Olive snails, also known as olive shells and olives, scientific name Olividae, are a taxonomic family of medium to large predatory sea snails with smooth, shiny, elongated oval-shaped shells. The shells often show various muted but attractive colours, and may be patterned also. They are marine gastropod molluscs in the family Olividae within the main clade Neogastropoda.
The olive snails are all carnivorous sand-burrowers. They feed mostly on bivalves and carrion and are known as some of the fastest burrowers among snails. They secrete a mucus similar to that of the Muricidae, from which a purple dye can be made.
Physically the shells are oval and cylindrical in shape. They have a well-developed stepped spire. Olive shells have a siphonal notch at the posterior end of the long narrow aperture. The siphon of the living animal protrudes from the siphon notch.
The shell surface is extremely glossy because in life the mantle almost always covers the shell