These attractive univalve molluscs are highly valued by shell collectors. They usually grow to around 10cm in length and have very distinguished colours and patterns on their shells.
Cone shell - image Geographer cone
At the narrow end of the shell they have an extendable proboscis. Using this proboscis they can jab a minute harpoon with 1 to 20 radular teeth penetrating skin to inject venom to immobilise their victim.
The toxins vary between different species. The fish-eating cone shells are probably the only ones dangerous to humans.
Scientists have identified more than 60,000 species of univalves.