Rare Fossil of Predator Choking on Prey to be Auctioned

An extraordinary fossil of an ancient predatory amphibian that apparently asphyxiated while preying upon a creature that would turn out to be its last meal is on an upcoming auction block at Heritage Auctions.

The auction house reports that both the amphibian, an early Permian-era creature known as Sclerocephalus haeuseri, and a smaller amphibian, presumably Cherlyderpeton latirostris, are both excellent fossil specimens in their own right, but for geology to have captured them together at the moment of death is all the more exquisite.

The event took place nearly 300 million years ago, the more than 2 foot-long predator choking on its prey, which was eaten alive. Fossils of a predator choking on its prey are known as aspiration specimens.

Heritage Auctions said it is aware of no such other aspiration specimens of S. haeuseri.

The fossilized creatures lived in an arid climate at a time several tens of millions of years before the dawn of dinosaurs, when amphibians ruled the Earth. Permian-era amphibians could grow up to 16.5 feet long and many of them were top predators of their day. Nearly all of the Permian-era amphibians were eventually wiped out as a result of a global climate change known as the Permo-Triassic Extinction event, which saw 90 percent of all living species become extinct over a geologically brief period of time. It was the greatest such extinction ever to occur.

Because the fossilized creatures are entombed in an aspiration specimen, the value of the fossil increases tremendously.

"It affects it to the degree of eight or 10 times without any trouble at all," Jim Walker, director of the nature and science department at Heritage Auctions, told LiveScience. The opening bid for the specimen starts at $75,000 and the lot is expected to fetch between $150,000 and $250,000.

Online bidding is open until Oct. 19, live bidding takes place on Oct. 20.

In November a rare fossil of two dinosaurs locked in mortal combat will go on the auction block at Bonhams in New York City. The two nearly complete skeletons, found in Montana in 2006 in the fossil-rich "Hell Creek" formation, are expected to fetch anywhere from $7 million to $9 million.