Ivory Tusk Shell (Graptacme eborea Conrad, 1846): Marine Beads?

This delicate conical shell at first glance appears to be a spine of some sea creature (an urchin, perhaps?), but upon closer inspection you will notice that it is open at both ends and curves slightly. The Ivory Tusk Shell may grow as long as 2 inches. The shell is smooth, with a few fine ridges and a tiny slit near the small end. The mollusk lives in the sand of marine waters with the small end sticking up just above the surface of the sediment. From the larger end the animal's foot protrudes. The Ivory Tusk can dig with this foot. In fact, the word “Scaphopod” means “plow-footed.”

It feeds on small protozoans (Foraminifera) in the sea water, and may be found near the shore from North Carolina to Texas and the West Indies.

In earlier centuries, tusk shells were used by various Native American tribes, especially in the Northeast of this country, as money and jewelry. The larger size tusk shells were cut into sections to make beads.

Notes

The specimens pictured here were found at Myrtle Beach, South Carolina.
For more information on the Ivory Tusk Shell see:
- R. Tucker Abbott and Percy A. Morris, Peterson Field Guides: Shells of the Atlantic & Gulf Coasts & the West Indies.
- Edward E. Ruppert and Richard S. Fox, Seashore Animals of the Southeast.
Classification: Family Dentaliidae; Order Dentaliida; Class Scaphopoda; Phylum Mollusca.
Scientific nomenclature is subject to change, due to ongoing research. The above classification corresponds to that published by the Integrated Taxonomic Information System.
Digital formatting is by Jonathan Mitchell.

Ivory Tusk Shell: Fragile Cone

Notes

Ivory Tusk Shell:
Fragile Cone