Placodus was a very large, heavily built reptile that probably lived on shellfish. It had spade-like teeth at the front of its mouth for chipping shellfish off rocks. The broad blunt teeth at the back of its mouth were used to crush the shells before the meat was swallowed. Placodus was a stocky, clumsily built animal that would have found it awkward to move about on land. Some species developed heavy armour like that of a turtle.
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