Rare, nearly complete fossil reveals giant among Jurassic sharks – CNET

SCIENCE

This illustration shows what the hybodontiform shark Asteracanthus might have looked like, along with silhouettes showing the shark next to a person for scale.


Sebastian Stumpf/Fabrizio De Rossi

Sharks tend to be much harder to find preserved in fossil form than their bony dinosaur buddies. Shark cartilage breaks down, which is one reason a spectacular shark fossil found in Bavarian limestone is worthy of celebration. It’s big, it’s nearly complete and it’s a rare window into the sharky side of the Jurassic past.

The University of Vienna described the fossilized Asteracanthus as « an exceptionally well-preserved skeleton » in a statement on Thursday. The shark swam in a lagoon area 150 million years ago during the Late Jurassic period.

This image shows illustrations and a photo of the fossilized Asteracanthus shark, which was found as a nearly complete skeleton.


Sebastian Stumpf: life reconstruction/Fabrizio De Rossi

The shark measured in at 8.2 feet (2.5 meters) long, making it « a giant among Jurassic sharks. » The animal was previously known, but not in the kind of detail scientists now have after this fossil find.

« Asteracanthus was scientifically described more than 180 years ago by the Swiss-American naturalist Louis Agassiz on the basis of isolated fossil dorsal fin spines, » the university said. « However, articulated skeletal remains have never been found — until now. »

A research team led by paleontologist Sebastian Stumpf of the University of Vienna published a study on the shark in the journal Papers in Palaeontology this week.

The extinct shark, part of a group known as hybodontiformes, is a close relative of modern sharks. The fossil offered up over 150 teeth, which it would have put to good use on its prey. 

« Asteracanthus was certainly not only one of the largest cartilaginous fishes of its time, » Stumpf said, « but also one of the most impressive. »

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