Placodus

Like Paraplacodus, Placodus  (meaning "flat toothed") has protruding teeth at the front. However they are shorter, thicker and more spoon-shaped. The crushing teeth are not confined to the edges of the mouth but a form a broad pavement across the palate, and the skull is particularly strong to withstand the stresses of crushing seashells. A row of bony scutes forms a jagged ridge along the back. A gap on the top of the skull may have held a life-sensitive organ.