Dunkleosteus first appeared in the Late Silurian, and the group became extinct during the transition from the Late Devonian to the Late Carboniferous, leaving no descendants. It lasted barely 50 million years compared to the 400 million year-long history of sharks. It preyed on Stethacanthus and Cladoselache.
Description
This top predator was up to 11.5 ft (3.5 m) long and had large, scissor-like cutting jaws with serrated, razor-sharp bones but no teeth. Its skull was over 2 feet (65 cm) long. It had a jointed neck, an eel-like tail, a scale-less body, and hinged body shields.
References
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