52 Tonicella marmorea

52 Tonicella marmorea

Length 32mm. LWS. Isle of Lewis, Scotland. April 2018. Leg. D.W. McKay & S. Taylor.
The transverse muscle which holds the valves together is often the same colour as that of the jugal tract; white, yellow or pink (1).
When the chiton rolls into a defensive ball, it increases proction to the foot, but exposes the stretched transverse muscle.

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