About Callianax biplicata (G.B.Sowerby I, 1825)
The shell of Callianax biplicata is quite solid, and is large for an Olivella species. Adult shells of this species range from 20 mm to 27 mm in length, which is about one inch. The shell is smooth, shiny, and elongated oval in shape. The shell is often some shade of greyish purple, but it can also be whitish, tan, or dark brown. Darker-colored forms often have a rich yellow band above the suture on the spire. At the anterior end of the long narrow aperture, there is a siphonal notch, from which the living animal's siphon protrudes. Callianax biplicata snails are found along Eastern Pacific Ocean coasts, ranging from British Columbia, Canada to Baja California, Mexico. This species is common on sandy substrates in intertidal and subtidal zones, in both bays and the outer coast. Native people of central and southern California have used the shell of this species to make decorative beads for at least the last 9,000 years. Beads made from these shells have been discovered in archaeological sites as far inland as Idaho and Arizona. Within the past 1,000 years, these beads began to be manufactured in large quantities on southern California's Santa Barbara Channel Islands, indicating that they were used as shell money in Native American trade. The historic Chumash people called this species anchum.
