Chitons belong to a class of mollusks called the Polyplacophora (Greek for “bearers of many plates”). Their bodies are covered by eight (rarely seven) shelly plates, also known as valves. The valves are interlocked and surrounded by a leathery girdle. The Striate Glass-hair Chiton, Acanthochitona pygmaea (Pilsbry, 1893), is one of two species of chitons found in shallow-water along the coast of SW Florida. The Striate Glass-hair Chiton may reach a little more than 0.5 inch in size and its valves are partially covered by a very broad girdle. The valves color can vary, ranging from green to orange, red, burgundy, brown, and others.
The girdle has two rows of tufts of glass-like bristles, each tuft resembling a minute bottle brush. The color is very variable: valves may be green, red, orange, or with many combinations of these colors. Do not confuse this species with its more common local relative, the similar-sized Eastern Beaded Chiton, Chaetopleura apiculata, which has a very narrow girdle that covers the shell valves only minimally. The chiton illustrated above was found on Bunche Beach (Fort Myers), crawling on a Sunray Venus shell.
The 12 mm-long (about 0.5 inch) Striate Glass-hair Chiton with greenish valves in the photo above was first observed by Lorin Buckner, who found it inside an empty clam shell near the Sanibel Causeway (SW Florida). I took some photos, and after downloading the images from my camera to the computer, I discovered that there were small fecal pellets ( red arrow) near the chiton's posterior end (left end of the image). Fecal pellets are agglutinated meal leftovers that can yield valuable information about animal diets.