Radula, 8.5 mm long, removed from sac. From 26 mm long specimen. Dorset, England. April 2017.
Left: in water.
Right: dried. Hyaline shield and radular ribbon contracted and folded under causing paddle-like major (third) uncinal teeth (1) to project; enlarged in inset (1a).
Upper two: dorsal face. Lower two: ventral face.

The teeth are pale when initiated at the rear of the radular sac (2) . They harden and darken to bright rust and black (3) as they are moved forwards along the radula and incrementally mineralized by the walls of the sac. In each row, a pair of tricuspid, major-lateral teeth, the largest and darkest, are the principal scrapers, and a pair of paddle-like major (third) uncinal teeth (1) sweep up loosened food particles.
Radula length 33% of body length.

KEY ID FEATURES : 01 Acanthochitona fascicularis