Conus marmoreus Linnaeus, 1758 - marbled cone snail shell (abapertural view), modern (latest Holocene). (public display, Bailey-Matthews Shell Museum, Sanibel Island, Florida, USA)

The gastropods (snails & slugs) are a group of molluscs that occupy marine, freshwater, and terrestrial environments. Most gastropods have a calcareous external shell (the snails). Some lack a shell completely, or have reduced internal shells (the slugs & sea slugs & pteropods). Most members of the Gastropoda are marine. Most marine snails are herbivores (algae grazers) or predators/carnivores.

The conid gastropods (cone shells) are fascinating marine snails for a couple reasons - they have attractively-shaped, colorful shells and they are killers. The conids are predatory, as are many other marine snails, but they take down their prey in an unusual fashion. The radula of most snails is a mineralized or heavily sclerotized mass of small teeth that scrapes across a substrate during feeding. Conid snails have a toxoglossate radula - one that has been evolutionarily modified into tiny, unattached, toxin-bearing, harpoon-like darts (see photo - science.naturkundemuseum-bw.de/files/images/niederhofer_2...) that can be fired at prey. Each dart is an individual tooth. The nickname "killer snails" is well deserved (even people have been killed). Some species have incredibly powerful toxins, while in other species the toxin has little effect on humans.

Classification: Animalia, Mollusca, Gastropoda, Neogastropoda, Conoidea, Conidae

More info. at: en.wikipedia.org/wiki/Conus and