Cryptochiton stelleriGiant Pacific Chiton
Geographic Range
Alaska to Channel Islands, California to Japan
- Biogeographic Regions
- oriental
- oceanic islands
- pacific ocean
Habitat
Among rocks, near low-tide level to water 60' (18 m) deep. May be found in shallow waters during spawning season in May.
- Aquatic Biomes
- coastal
Physical Description
Commonly called the gumboot "chiton," Cryptochiton stelleri is the world's largest chiton species, reaching a length of 14 inches.
- Other Physical Features
- ectothermic
- bilateral symmetry
Reproduction
Separate sexes; males deposit sperm into water and females lay eggs in strings, clusters or spiral arrangements. Eggs may be free-floating single cells or enclosed in jelly-like capsules or strings.
Behavior
Usually nocturnal, browse surface of intertidal rocks for food. They also have an amazing ablility to cling to rocks.
Food Habits
Feeds on various fleshy and coraline algae such as sea lettuce, also on bryzoans and diatoms.
Economic Importance for Humans: Positive
Some species of chitons are often found in Indian and West Indian foods, and they are used as bait.
Conservation Status
Common.
-
- IUCN Red List [Link]
- Not Evaluated
Other Comments
There are over 600 species of chitons, and one of the most diverse groups is found on the Pacific Coast. To keep its surface clean of other organisms, a chiton secretes a mucus that swells on contact with water. This touh mantle completely covers the chiton's eight transverse shell plates, and prevents foreign organisms from attaching to the spines of the girdle.
Contributors
Almaz Kinder (author), University of Michigan-Ann Arbor.
Glossary
- Pacific Ocean
-
body of water between the southern ocean (above 60 degrees south latitude), Australia, Asia, and the western hemisphere. This is the world's largest ocean, covering about 28% of the world's surface.
- bilateral symmetry
-
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
- coastal
-
the nearshore aquatic habitats near a coast, or shoreline.
- ectothermic
-
animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- oceanic islands
-
islands that are not part of continental shelf areas, they are not, and have never been, connected to a continental land mass, most typically these are volcanic islands.
- oriental
-
found in the oriental region of the world. In other words, India and southeast Asia.
References
Abbott, R.T. 1954. American Seashells. D. Van Nostrand Co., Inc.
Abbott, R.T. 1986. A Guide to Field Identification: Seashells of North America. Golden Press, New York.
Cernohursky, W.O. 1967. Marine Shells of the Pacific. Pacific Publications.
Morris, P.A. 1966. A Field Guide to Shells of the Pacific Coast and Hawaii. Houghton Mifflin Company,Boston.
Rehder, H.A.1994. National Audobon Society Field Guide to North American Seashells. Chanticleer Press, Inc., New York.
Rogers, J.E. 1908. The Shell Book. Charles T. Branford Co., Publishers, Boston.
Sabelli, B. 1979. Simon & Shuster's Guide to Shells. Simon & Shuster, Inc.