01 Tonicella marmorea

01 Tonicella marmorea

Length 32 mm. LWS. Isle of Lewis, Scotland. April 2018. Leg. D.W. McKay & S.Taylor.
In the N.E. Atlantic, T. marmorea grows to a maximum of 45 mm long and 27mm wide.
To the naked eye, the girdle and valves appear smooth, apart from near-rectangular, distinct, growth lines on the valves.