Gumboot chiton

Natural history

The gumboot's grip  is not quite as strong as other chitons. It can become dislodged during bad weather and wash ashore.

The gumboot uses its tonguelike radula to scrape algae from rocks. The radula has many tiny teeth capped with magnetite, an iron mineral harder than stainless steel. The teeth contain so much magnetite that a magnet can pick them up!

Conservation

The gumboot is one of about 650 species of chitons that have remained virtually unchanged for over 500 million years. The gumboot has simple body parts and requires little food. It has relatively few predators, which include sea stars, sea otters, and the lurid rock snail.

When you see chitons or other tide pool creatures, it's best just to look, not touch so the animals stay safe and undisturbed in their rocky shore homes.

Cool facts

• The gumboot is nocturnal and usually feeds at night.
• The gumboot chiton is the largest chiton in the world. It can live 20 years or more!
• When exposed to air during low tide, the gumboot can breathe oxygen from the atmosphere as long as its gills stay moist.
• A gumboot can repair breaks to its shell plates, as such damage is a common occurrence.
• Commensal polychaete worms (Arctonoe vittata and Arctonoe pulchra) are often found living around the gumboot’s pallial groove.