The Eastern Beaded Chiton
Last week, I introduced the Striate Glass-Hair Chiton, mentioning that that species was the less common of two local shallow-water species of Chitons. Today, I present the other species, the more commonly found Eastern Beaded Chiton, Chaetopleura apiculata (Say, 1838). Chitons belong to a class of mollusks named the Polyplacophora (Greek for "bearers of many plates"). The Chiton shell is divided into eight (rarely seven) plates, or valves. The valves are interlocked, and are surrounded by a tissue called the girdle. The Eastern Beaded Chiton may reach one inch in size. As the common name implies, the external surface of the valves are covered with minute beads. The valves are only minimally covered by a narrow girdle (the girdle itself is covered with microscopic scales). The color in this species is very variable: valves may be orange, pink, cream, green, gray or showing many combinations of these colors. The Chitons in the illustration were collected inside valves of Pen Shells by José H. Leal and Kim Nealon on Turner Beach (Captiva) in December 2003.
Eastern Beaded Chitons from Captiva Island. Photo by José H. Leal.