Chitons

Chitons, sometimes referred to as 'sea cradles' or 'coat-of-mail shells', are in a large group (phylum) called mollusks that also include abalone, limpets, snails, sea slugs, clams, mussels, and octopus.  They range in color from bright to well camouflaged, and have a series of eight plates or valves held together by an outer girdle.

 

     
 Mossy Chiton (Mopalia muscosa)  
 mossy chiton Description: Often found in tidepools or on rocks. Stiff hairs on girdle. Dark brown, gray or black in color. A chiton's body consists of eight overlapping shell plates (valves) bound together by a leathery girdle. Lacking eyes or tentacles, chitons can still sense light level through light-sensitive organs in its shell. Unaffected by silt deposition. The plates are often covered by barnacles, seaweeds and other life. To 2.75 in (7 cm) in length.  
 Food: Scrapes algae from rocks with its radula - a rasping, tongue-like appendage.  
 Reproduction: Separate sexes. Gametes released into the water column where fertilization takes place.  
 Fun Facts: This species moves and feeds only at night when covered by water.  
   

 

Hairy Chiton

 

(Mopalia ciliata)

 
 Hairy Chiton Description: Found in protected locations such as under rocks in the intertidal zone. Soft hairs on girdle. Varies in color from darks to lights. A chiton's body consists of eight overlapping shell plates (valves) bound together by a leathery girdle. Lacking eyes or tentacles, chitons can still sense light level through light-sensitive organs in its shell. To 3 in 8 cm) in length.  
 Food: Scrapes algae, sponges, bryozoans and hydroids from rocks with its radula - a rasping, tongue-like appendage.  
 Reproduction: Separate sexes. Gametes released into the water column where fertilization takes place.  
 Fun Facts: Valves sometimes display colorful patterns of streaks and splotches.  
   

 

Lined Chiton

 

(Tonicella lineata)

 
 Lined Chiton Description: Found intertidally on rocks, grazing on algae. Beautiful colors ranging from orange, red and pink. Alternating light and dark zig zag lines on the plates. A chiton's body consists of eight overlapping shell plates (valves) bound together by a leathery girdle. Lacking eyes or tentacles, chitons can still sense light level through light-sensitive organs in its shell. To 2 in (5 cm) in length.  
 Food: Scrapes coralline algae from rocks with its radula - a rasping, tongue-like appendage.  
 Reproduction: Separate sexes. Gametes released into the water column where fertilization takes place.  
 Fun Facts: This colorful species is preyed upon by the ochre and six-rayed sea stars.  
   

 

Black Chiton

 

(Katharina tunicata)

 
 Black Chiton Description: Common in exposed wave-swept or high current areas to mid-intertidal. Black to brownish girdle mostly covering the gray to white plates. A chiton's body consists of eight overlapping shell plates (valves) bound together by a leathery girdle. This species is tolerant of light, and can be found in the open. To 4 in (10 cm) in length.  
 Food: Scrapes algae and animal life from rocks with its radula - a rasping, tongue-like appendage.  
 Reproduction: Separate sexes. Female lays green eggs in the summer.  
 Fun Facts: These chitons were traditional fare of the Native peoples of the region, and are the subject of many folk tales. This chiton only lives for three years.  Also known as the black Katy chiton.  
   

 

Gumboot Chiton

 

(Cryptochiton stelleri)

 
 Gumboot Chiton Description: Mostly subtidal but found on rocky beaches at lowest tides. A chiton's body consists of eight overlapping shell plates (valves) bound together by a reddish brown leathery girdle; which in this species totally encloses the plates. Lacking eyes or tentacles, chitons can still sense light level through light-sensitive organs in its shell. To 13 in (33 cm) in length.  
 Food: Scrapes algae and animal life from rocks with its radula - a rasping, tongue-like appendage.  
 Reproduction: Separate sexes. Gametes released into the water column where fertilization takes place.  
 Fun Facts: The largest chiton in the world, this animal can live for more than 20 years! Gumboot chiton's are also edible. This species radula is covered in magnetite (an ore of iron) to the extent that it can be detected with a metal detector.