Anterior of radula. From 26 mm long specimen. Dorset, England. April 2017.
As on chitons generally, A. fascicularis has a broad radula with extremely strong, hard teeth of chitin mineralized with rust-coloured or iron-black magnetite (so iron rich that it adheres to a magnet) in rows of seventeen.
The anterior of the radula is flanked by a hyaline shield (1) and is supported by a cartilaginous odontophore when grazing rock surfaces.
A. fascicularis feeds by scraping micro algae and associated organisms from the rock surface with its radula. 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 sweep up loosened food particles.

KEY ID FEATURES : 01 Acanthochitona fascicularis