Rolfosteus had a skull reaching 11.5 centimetres (4.5 in),[1] with tough plating on the front of its body. Like other arthrodires, such as Coccosteus and the giant Dunkleosteus, it had sharp, bony plates on its mouth which formed a turtle-like beak for cutting prey to pieces. Rolfosteus's most unusual feature was its highly elongated rostrum (snout), which may have been used to enhance its sense of smell as well as increase its hydrodynamic streamlining, making it well adapted to be a pelagicpursuit predator. Its fast jaw movement and jaw morphology allowed it to effectively capture prey and swallow them whole.[2]