Chitons are a group of molluscs that inhabit the intertidal and subtidal
regions, and are called Polyplacophora because they bear many plates on
These eight overlapping plates are a distinctive characteristic of all chitons, and are usually visible on the chiton's back. When viewed from the bottom, there is a large central foot used for creeping and adherence to the substrate. The head is found in front of the foot, but really only consists of a short squat protuberance with the mouth at the tip.
The gumboot chiton is one species of chiton that is a little different
from the rest; it is the largest species of chiton in the world, growing
up to 30 cm in length - and its eight plates are covered up by thick,
leathery, brick-red flesh so we cannot see them.
The broad and flat foot on the front of the chiton functions in adhesion
as well as locomotion. Chitons creep slowly in the same manner as
snails by waves of muscular activity along the foot, called "pedal
waves". The division of their shell into eight plates helps
them to adhere to the sharply-curved surfaces of the rocky intertidal.
like many molluscs, posses a feeding structure known as a radula.
The radula is a firm band made out of chiton (a hard organic
material) with two rows of sharp teeth that are scraped over
a surface to pick up bits of the food. Gumboot chitons use
their radula to eat mainly algae growing on rocks.
dioecious, meaning there are female chitons and male chitons.
Sperm are released by males into the water and taken up by
females. Fertilized eggs are then shed singly or in gelatinous
strings. These develop into a trochophore larva, which later
metamorphs into the adult form of the chiton.
more info and picture of chitons, check out these cool
Gumboot chiton information and a video from Race Rocks
check out "Chitons.com"!
ready for the Chiton
Test your knowledge of the Polyplacophorans!
J. A. Pechenik. Biology of the Invertebrates, 4th edition. Migraw-Hill Companies, Inc. Toronto, 2000.
R. D. Barnes. Invertebrate Zoology, 5th edition. Saunders College Publishing, Toronto, 1987.
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