Dunkleosteus Fact Sheet

Common Name:

Dunkleosteus terrelli

Scientific Name:

Dunkle's bone

Wild Status:

Devonian Period, 382-358 MYA


North America, Poland, Belgium, Morocco


Poland, Belgium, Morocco, Countries in North America



Life Span:



20 feet long, 1.1 tons

Cool Facts:

  • Even though it was a top predator that could prey on just about any other animal it wanted to, Dunkleosteus could not digest bone. It is common to find masses of partially digested fish bones associated with Dunkleosteus fossils. This indicates that they routinely regurgitated the inedible parts of prey.
  • Dunkleosteus is only known from its head armor. Its body was made made of cartilage and does not preserve in the fossil record. As a result of this, scientists do not know for sure exactly what the animal looked like in life.


Dunkleosteus is a member of an extinct group of fish known as placoderms. Placoderms had bony armor covering the upper third of their bodies, and were the first fish to evolve teeth and pelvic fins. Instead of teeth, Dunkleosteus’s jaws contained sharpened bony plates that functioned like a guillotine. Due to a specialized joint between its head and neck, Dunkleosteus was able to open its jaws in 20 milliseconds to suck prey into its maw before slamming them shut with more than 1500 pounds of bite force to shear them to pieces. At the time, it was the largest and most powerful predator on the planet.

Taxonomic Breakdown:

Kingdom - Animalia Phylum - Chordata Class - Placodermi Order - Arthrodira Family - Dunkleosteidae Genus - Dunkleosteus Species - D. terrelli

Conservation & Helping:

Dunkleosteus is currently extinct and lived from 382 to 358 million years ago.

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