The giant 23-foot-tall sea beast took down wild, razor-toothed prey 246 million years ago.

The remains of an ancient sea-dwelling reptile have been declared the oldest of its kind in the southern hemisphere.

A paper published Monday in the journal Current Biology identified the notosaurian bone, discovered nearly five decades ago, as a record-breaking fossil.

At about 246 million years old, this fossil is more than 40 million years older than the oldest known fossils in the region.

Clues about the life of the notosaurus were preserved in a fragment of its spine. The dorsal vertebra of this animal was extracted from a boulder in a riverbed in the South Island of New Zealand.

The researchers concluded that this polar sea giant could have been up to seven meters or 23 feet long. As it hunted for squid and fish, it could paddle through the water with oar-like limbs.

Notosauruses were characterized by flat skulls and a bite of thin, cone-shaped teeth.

It was a promising find, but the fossil’s significance only became clear when paleontologists from Sweden, Norway, New Zealand, Australia and East Timor teamed up to conduct the analysis.

Scientists examined the vertebrae and related fossils and found that the piece belonged to one of the earliest known marine reptiles.

Dr. Benjamin Kerr, lead author of the paper, said: “We show that these ancient marine reptiles lived in a shallow coastal environment rich in marine life in the Antarctic Circle.

polar diving

Nearly 250 million years ago, New Zealand was located on the south polar shores of a huge global ocean called Panthalassa.

Sea-dwelling reptiles thrived in Antarctica due to global warming.

When a mass extinction event destroyed marine ecosystems, it gave way to the age of dinosaurs, known as the Mesozoic.

The most diverse group of marine reptiles were marine reptiles.

Despite having an evolutionary history of more than 180 million years, scientists’ knowledge was largely limited to the northern hemisphere before the study.

Using a time-calibrated evolutionary model of the global distributions of sauropterygians, we show that notosaurs originated near the equator, then rapidly expanded north and south as complex marine ecosystems rebuilt after the catastrophic mass extinction that marked the beginning. have found Kiyar said: Age of dinosaurs.

The area where this fossil was found is known as the Cantebury area of ​​New Zealand. Due to the abundance of marine sedimentary rocks, it is full of fossils.

Among the discoveries were the remains of ancient human-sized penguins in 2018.

An amateur paleontologist stumbled across its bones Crossvallia waiparensisA giant bird from the Paleocene era, between 66 and 56 million years ago.

Scientists believe there are more clues to discover.

“Undoubtedly, there are many more fossilized remains of extinct sea monsters in New Zealand and elsewhere in the Southern Hemisphere waiting to be discovered,” Keir said.

Timeline of life on earth