5.1" Hybodus Shark Dorsal Spine - Cretaceous

Hybodus Shark Dorsal Spine - Cretaceous #73115

This

A complete fossil of Hybodus from Germany showing placement of spine. Image under GNU Free Documentation License

is a nice dorsal spine of the extinct Cretaceous aged shark Hybodus. These large spines helped to support the dorsal fins of the shark.

There are multiple repaired cracks through this specimen.

Hybodus was a small shark that grew up to 2 meters in length and was likely an opportunistic predator. It had a streamlined shape ideal for hunting down fast prey and two different types of teeth: sharp cutting teeth for catching prey and flatter grinding teeth for crushing. This combination may have been the key to Hybodus' success.

A paper on Hybodus spines can be found below.

Growth And Form of Finspines In Hybodont Sharks

A complete fossil of Hybodus from Germany showing placement of spine. Image under GNU Free Documentation License