Habitat: Horned helmet typically are found on sandy banks, inside barrier reefs.
Average adult size: Adults can grow to 1 foot long.
Natural history: Cassis cornuta is the largest species of helmet snail. They are found in shallow water on the sand. During the day, they usually burrow down so only the tops of their shells are exposed. At dusk, they move out to hunt. Most members of this family feed on sea urchins and sand dollars. They follow the scent trail of the urchin and clamp down on its shell, seemingly unafraid of the urchin's sharp spines. The Horned Helmet also has been known to prey on the Crown-of-Thorns sea star.
Range: Indian ocean to the Hawaiian Islands.