T. Rex Dethroned? A Stegosaurus Fossil Sells for a Record $44.6 Million.

Sotheby’s sold an unusually complete stegosaurus fossil at auction on Wednesday for a staggering $44.6 million, toppling the record fossil price that had previously been set by the king of the dinosaur world, the Tyrannosaurus rex.

The unexpectedly high price — which was more than 10 times the low estimate — shows that the market for prehistoric specimens is continuing to explode, which concerns paleontologists who fear that scientists could be priced out of the market.

With its trademark back plates and cavernous rib cage, this stegosaurus, which is said to have walked the Earth about 150 million years ago in what is present-day Colorado, was nicknamed Apex because of its exceptional quality. It was the subject of a 15-minute bidding war with seven bidders from around the world on the phone.

The auction house confirmed that the buyer was American but declined to reveal the buyer’s identity, saying the person intended to “explore loaning the specimen to a U.S. institution.”

Four years ago, the commercial fossil market was jolted by the sale of a T. rex skeleton called Stan that fetched a record $31.8 million, setting off a gold rush for dinosaur fossils in the American West and alarm bells for academics who fear that the spiking prices could push fossils out of the reach of museums and universities that wish to study them.

The $44.6 million sale of the stegosaurus fossil, which includes buyer’s fees, eclipsed the record set by Stan, which ended up at a developing natural history museum in Abu Dhabi, the capital of the United Arab Emirates. Apex, which stands 11 feet tall and 27 feet long, is among the largest of its kind.