Cone Shells, Family Conidae

Family Conidae

Cone Shells

Cone shells are well-known since they possess a powerful sting used to capture prey. Many have been fatally wounded when handling live cones, especially those that feed upon mollusks and fishes. If one must, the least dangerous method is to hold the shell at the widest point and be prepared to let go if the animal extends itself. Never place live cones in a pants pocket, wetsuit, or bag close to the body. Cones are prey-specific, feeding upon worms, mollusks, or small fish, those that eat worms having the weakest venom, probably comparable to a bee sting. The sting comes from a hollow harpoon dart called the radula. It is rapidly thrust into living prey by the extensible mouth or proboscis and venom is pumped into the wound and more radulae may employed until it dies. Then it can be swallowed by expanding the proboscis much like a snake would swallow its prey. The barbed radula also assists in pulling prey into the mouth.

A living cone animal has a long foot and the head is located at the narrow end of the shell. A flap of tissue called the mantle lines the inside of the shell and is rolled to form a siphon that extends beyond the shell and draws water into the gills. The often-banded siphon is mistaken by observers for the stinging proboscis which is normally retracted and of a single color. Each species' soft-parts has a distinct color pattern allowing experienced divers to identify it even if the shell is totally encrusted with algae.

There are at least 500 species in the world's warm waters and are very popular with shell collectors, but living shells are well-camouflaged or buried in sand. While living the shell is covered with a brown skin-like periostracum which is the foundation for shell development. The periostracum in turn becomes encrusted with coralline algae in species that do not completely bury themselves. It can be removed by soaking the empty shell in chlorine bleach overnight and scrubbing with a stainless steel wire brush. Living shells often become eroded or chipped and permanent scars are visible. There is a considerable degree of variation in the coloration and pattern within some species (see Conus pulicarius). Many species also have a bumpy or coronated spire.

Note: Species are grouped here according to appearance for easier comparison. I have elected to keep parent genus Conus instead of the current (and confusing for the layperson) splitters' trend of elevating subgenera to genus. Here subgenera are indicated within parentheses.

Prey items