Shell Museum friend and photographer Amy Tripp captured this great image of seven Eastern Beaded Chitons, Chaetopleura apiculata, "hitchhiking" on an Alphabet Cone snail, Conus spurius, on Kice Island, to the south of Marco Island, Florida. Chiton shells are divided into eight ( or very rarely seven) plates, or valves. They belong to a class of mollusks named Polyplacophora (from the Greek words for "many," "plates," and "bearers"). The plates are interlocked, and are surrounded by a fleshy tissue called the girdle. Eastern Beaded Chitons are small, reaching only about an inch in size, but are usually found in the ½- to ¾-inch range. As the common name implies, the external surfaces of the shell plates of Eastern Beaded Chitons are covered with minute beads. As the image shows, there is much variation in the color pattern in this species: valves may be orange, pink, cream, green, gray, or showing many combinations of these colors. We don't know exactly why the chitons are hitching a ride on the "back" of the cone snail shell, but the chitons' need for a solid, hard structure to live on may be one of the reasons.
José H. Leal
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