Researchers have discovered a Japanese mosasaur that lived 72 million years ago and was as big as a great white shark.
This mosasaur had extra-long rear flippers and a long finned tail that likely helped it swim.
Unlike other mosasaurs, it had a dorsal fin like a shark, which aided in quick and precise turns.
More about the creature
A special kind of ancient sea creature called a mosasaur was discovered in Wakayama Prefecture, Japan.
It's the most complete skeleton of its kind ever found in Japan or the northwestern Pacific.
This mosasaur has some unusual features, like longer back flippers and a head that looks like a crocodile.
Because of these unique traits, scientists are having a hard time figuring out exactly where it belongs in the animal family.
Mosasaurs were really strong predators that lived at the same time as dinosaurs.
They became extinct around the same time as the dinosaurs.
Scientists decided to put this particular mosasaur in a group called Mosasaurinae and gave it the name Megapterygius wakayamaensis. The name Megapterygius means "big flippers" because of its large flippers.
The function of the large flippers is not fully understood, as no modern animal has a similar body shape.
Researchers speculate that the front flippers aided in maneuvering, while the rear flippers helped with diving or surfacing.
The mosasaur's tail would have provided fast acceleration for hunting.
Why it's important
The discovery challenges existing knowledge about how mosasaurs swam and adds to our understanding of these ancient marine reptiles.
Previously, we talked about sugar gliders.
