Look up: placodus

1. 
   Placodus
   Placodus was a marine reptile (a placodont) that lived in shallow seas during the early to middle Triassic period . This air-breather had four legs, a short neck, a very large, wide head and two types of teeth (peg-like teeth in the front and large, flat teeth in the sides of the mouth). Its long tail was flattened and may have had a fin. Unlike Plesiosaurs and Ichthyosaurs , Placodus was not a very strong swimmer. It was about 7 feet (2.15 m) long. It ate shellfish, like oysters and clams, whic...
   Found on http://www.enchantedlearning.com/subject
   
   
2. 
   Placodus
   `Placodus` was a genus of 2.5 metre (6.5 foot) long marine reptiles, belonging to the order Placodontia, which swam in the shallow seas of the early to middle Triassic period (210 million years ago). The robust skull and teeth of `Placodus` show that they were specialized for a durophagous diet of shellfish such as bivalves. These animals would have plucked their hard-shelled benthic invertebrate prey from the substrate with protruding front teet...
   Found on http://en.wikipedia.org/wiki/Placodus
   
   
3. 
   Placodus
   (from the article `sauropterygian`) ...are the placodonts of the Middle Triassic Period (242 million to 227 million years ago). Their bodies were structurally similar to those of ...
   Found on http://www.britannica.com/eb/a-z/p/75