Dunkleosteus, one of the most intimidating fish ever. From the Devonian Era, known to all fish lovers as the Golden Age. Note the teeny-tiny human figure swimming underneath.
Leedsichthys, along with a number of other animals we have talked about in our "Top Ten: Extinct Sea Monsters:" Basilosaurus, Elasmosaurus, Dunkleosteus, Archelon, Megalodon, Tanystropheus, and, of course, Leedsichthys. Hesperornis is also on there, as well.
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Modelo móvil del placodermo artródiro Dunkleosteus.