# Gumboot Chiton (*Cryptochiton stelleri*)

> The gumboot chiton (Cryptochiton stelleri) is the largest chiton in the world, with a reddish leathery girdle on North Pacific rocks. Adults reach 30 cm and 1 kg and are Least Concern.

- **Category:** Invertebrate
- **Conservation status (IUCN):** Least Concern
- **Range:** North Pacific rocky shores from Alaska to California and Asia.
- **Canonical page:** https://globalanimalguide.org/animals/chiton/
- **Last reviewed:** 2026-07-16

## Scientific classification

- **Kingdom:** Animalia
- **Phylum:** Mollusca
- **Class:** Polyplacophora
- **Order:** Chitonida
- **Family:** Acanthochitonidae
- **Genus:** Cryptochiton

## Facts at a glance

| Attribute | Value |
| --- | --- |
| Scientific name | Cryptochiton stelleri |
| Diet | Herbivore |
| Habitat | Rocky intertidal |
| Lifespan | 20–30 years |
| Weight | 0.5–1.2 kg |
| Top speed | up to 1 km/h |
| Conservation status | Least Concern (IUCN) |

## Leathery coat over eight plates

Unlike smaller chitons with visible armour rings, the gumboot's plates are hidden under a thick reddish mantle. A broad foot grips wave-swept boulders.

## Algae scraper of surf zones

A rasping radula scrapes diatoms and macroalgae from rock surfaces. Slow movement suits intertidal and shallow subtidal zones.

## North Pacific rocky shores

From Alaska to California and across to Asia on exposed coasts. Large size makes it a tidepool landmark.

## Sturdy on the rocks

Least Concern across a long coastline. Collection for curiosity and localized pollution are minor compared with habitat extent.

## Frequently asked questions

### What is a chiton?

A marine mollusc with eight overlapping shell plates and a muscular foot — like a armoured slug.

### Why is it called gumboot chiton?

The thick leathery girdle resembles a reddish rubber boot covering the shell plates.

### How big is a gumboot chiton?

Up to about 30 cm — the world's largest chiton species.

### What do gumboot chitons eat?

Algae and biofilm scraped from rocks with a radula.

### Where can you find gumboot chitons?

Rocky North Pacific shores from Alaska to California.

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Source: Global Animal Guide (https://globalanimalguide.org/animals/chiton/). Licensed CC BY-NC 4.0 — free for non-commercial reuse with attribution.