Stethacanthus

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stethacanthus  
 * 0.7-2m long.
 * lived 370 to 345 million years ago.
 * It had strong muscular jaws and some teeth were on the lips.
 * Lived about 360 million years ago.
 *  Stethacanthus is best known for its unusually shaped dorsal fin.
 * it resembles an anvil or ironing board.
 * small spikes covered its crest and the sharks head as well.
 * some believe it was used for self defense. media type="youtube" key="HwvvkGqOr-Y" height="344" width="425"[[image:stethacanthus.jpg align="right" caption="It looks like photo shop"]]