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Key to Irish Chitons
Species Description


Tonicella marmorea (O. Fabricius, 1780) [back to the Key] | [next] | [previous]
Length: up to 40 mm in the North-eastern Atlantic (slightly smaller in the North-western Atlantic)

Tegmentum colour: white, lighter or darker red or brownish, often with large patches of reddish or dark brown, sometimes with narrow, alternating bands of light and darker red or with V-shaped white lines

Sculpture: Valves appear smooth, but covered with minute granules in quincunx. Many growth lines are easily visible, especially on the lateral areas and anterior margins of the intermediate valves.

Girdle: relatively broad, appears leathery to the naked eye, coloured with alternating zones of light and dark brown, or with light splotches

Bathymetric range: from low-water to 230 m

Geographic range: an artic-boreal species, found in the North Atlantic and North Pacific. In the north-eastern Atlantic Ocean, found from Greenland and Scandinavia to the North coast of France; found also in the Western Atlantic down to Massachusetts, and in the North Pacific from the Bering Sea to northern Japan.

Similar species: Boreochiton ruber


Taxonomy and Synonymy:

ORDER: Chitonida Thiele, 1909

FAMILY: Tonicellidae Simroth, 1894

GENUS: TONICELLA Carpenter, 1873

Tonicella marmorea (O. Fabricius, 1780)


List of synonymised names available at:


For more information on this species, see:

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