placodont

Most paleontologists consider the placodonts of the Middle Triassic Period (246 million to 229 million years ago) to be a subgroup of Sauropterygia. Their bodies were structurally similar to those of nothosaurs but more compact. Placodus was a typical form, having broad, flat tooth plates for crushing the mollusks…

†Order Placodontia (placodonts) Lower to Upper Triassic. Aquatic seallike reptiles with long tails and short limbs not modified as paddles; total length typically less than 2 metres (about 7 feet). Head often large with broad flattened jaw and palate teeth, likely for crushing mollusks. Skull with large…