Tonicella undocaerulea, commonly known as the Blue Lined Chiton, is a species of chiton

Chiton

Chitons are small to large, primitive marine molluscs in the class Polyplacophora.There are 900 to 1,000 extant species of chitons in the class, which was formerly known as Amphineura....

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Size and description

The Blue Lined Chiton has a head plate with zigzag white (may be blue when alive) concentric lines without a dark border. It commonly has bright electric blue stripes and flecks when alive. The girdle is hairless and brown to red or pink, often with yellow or white mottling.

Similar species

Tonicella lineata

Tonicella lineata

Tonicella lineata, commonly known as the lined chiton, is a species of chiton.-Size and description:T. lineata is a very colorful chiton, having blue, purple or black straight or zig-zag lines on each of the eight valves. The background color of the valves is often brown or red, but can also be...

is very similar but has a dark border to the concentric blue lines on the anterior plate. Tonicella lokii

Tonicella lokii

Tonicella lokii, commonly known as the flame lined chiton or Loki's chiton, is a chiton in the lined chiton genus Tonicella.-Size and description:...

is also similar but has radiating bands on the girdle. Mopalia spectabilis

Mopalia spectabilis

Mopalia spectabilis, commonly known as the Red-flecked Mopalia, is a species of chiton.-Size and description:M. spectabilis is a chiton that has a central area of plates 2-7 pitted in longitudinal rows. The girdle commonly banded light orange and brown. This species nearly always exhibits bright...

looks superficially similar due to its bright blue wavy lines on the valves

Valve (chiton)

Valve is an anatomical term applied to the shell of molluscs. Although in theory any mollusc shell can be termed a "valve", the word is now most commonly applied to members of two classes of molluscs: the Bivalvia and the Polyplacophora , in other words, to those molluscs whose shells are normally...

, but has a hairy girdle.

Distribution and habitat

The natural range of T. undocaerulea stretches from Kodiak

Kodiak, Alaska

Kodiak is one of 7 communities and the main city on Kodiak Island, Kodiak Island Borough, in the U.S. state of Alaska. All commercial transportation between the entire island and the outside world goes through this city either via ferryboat or airline...

, Alaska

Alaska

Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...

 to Point Conception

Point Conception

Point Conception is a headland along the Pacific coast of U.S. state of California, located in southwestern Santa Barbara County. It is the point where the Santa Barbara Channel meets the Pacific Ocean, and as the corner between the mostly north-south trending portion of coast to the north and the...

, California

California

California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

. It is commonly found on rocks in low intertidal and shallow subtidal waters.