A 67-million-year-old Tyrannosaurus rex fossil has been sold for £37.4 million (about $50.1 million) at a Sotheby's auction in New York, setting a new record as the most expensive dinosaur fossil ever sold.

The fossil, affectionately named Gus, stands more than 12 feet (4 metres) tall. Sotheby's said more than 60% of its bones were recovered, making it one of the most complete T. rex specimens ever discovered.

The identity of the winning bidder at Tuesday's auction has not been revealed.

Gus was discovered in 2021 on a remote ranch in the US state of South Dakota.

"This result has been years in the making," said Cassandra Hatton, Sotheby's worldwide head of science and natural history.

"Gus is not only an exceptional discovery but also a specimen that has been carefully excavated, documented, prepared and preserved," she said.

The sale broke the previous record set by the stegosaurus fossil Apex, which was sold in 2024. Gus is also the first dinosaur fossil to sell for more than $50 million.

Some scientists told the BBC that the record-breaking sale could signal a new era of fossil collecting by ultra-wealthy buyers.

Hatton said the high price reflects the years of work and resources needed to recover and prepare the fossil.

The excavation took place over three summers between 2021 and 2023, when the frozen ground had thawed enough for digging. It then took another three years in the laboratory to clean, study and assemble the skeleton.

Researchers found bite marks on the skull and signs that several broken ribs had healed while the dinosaur was still alive, suggesting it may have been injured while scavenging or fighting with other dinosaurs.

Although the buyer has not yet been identified, Gus may still be displayed for the public in the future. The previous record-holder, Apex, was loaned to the American Museum of Natural History for four years by its billionaire owner, Kenneth Griffin.

As a result, despite its record-breaking sale, Gus could eventually be exhibited in a museum.