Temporal range: Eocene–Recent
|Geography cone, Conus geographus|
|Conus species eating a small fish, in Guam|
Shaped, as the name suggests, like a cone, many species have colorful patterning on the shell surface. Conus snails are mostly tropical in distribution. Species in the genus Conus sensu stricto can be found in the tropical and subtropical seas of the world, at depths ranging from the sublittoral to 1,000 m. They are very variable in some of their characters, such as the tuberculation of the spire and body whorl, striae, colors and the pattern of coloring. Many fossil species have been described; they are extensively distributed, and first appear in Cretaceous strata.
All Conus snails are poisonous. They hunt and eat marine worms or molluscs. The larger ones prey on small bottom-dwelling fish. Cone snails use a hypodermic-like modified radula tooth and a venom gland to attack and paralyze their prey before eating it. The tooth is sometimes likened to a dart or a harpoon. It is barbed and can be extended some distance out from the mouth of the snail, at the end of the proboscis. They can "sting" humans, and should be handled with great care or preferably not at all.
Cone snail venoms are mainly peptides. The venoms contain many different toxins that vary in their effects; some are extremely toxic. The sting of small cones is no worse than a bee sting, but the sting of some larger species can be serious, occasionally even fatal to humans. According to Goldfrank's Toxicologic emergencies, only about 15 human deaths were caused by cone snail stings.
Cone snail venom has promise as a source of new, medically important substances.
The thick shell of species in the genus Conus sensu stricto, is obconic, with the whorls enrolled upon themselves. The spire is short, smooth or tuberculated. The narrow aperture is elongated with parallel margins parallel and is truncated at the base. The operculum is very small relative to the size of the shell. It is corneous, narrowly elongated, with an apical nucleus, and the impression of the muscular attachment varies from one-half to two-thirds of the inner surface. The outer lip shows a slight sutural sinus.
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