The most spectacular fossil of Queensland’s famed prehistoric reptile is displayed almost 10,000 miles away and locked in plaster. This is the remarkable tale of a wayward Australian sea monster at Harvard known as “Plasterosaurus.”

Kronosaurus queenslandicus once terrorized the Early Cretaceous inland seas of Queensland, Australia with jaws so big it could make the shark from Jaws blush. It looked something like a small whale with the jaws of a crocodile and would use its four paddles to fly through Australia’s primeval waters along with the many other large aquatic reptiles of its day. This is a good chance to address the confusing nature of Mesozoic sea reptile classification. Kronosaurus is the largest known pliosaur, a group with big heads and short necks. Pliosaurs are part of the overarching and similarly-named plesiosaur group. Thanks to museum displays and dinosaur books, most of us think of plesiosaurs as sea creatures with small heads and long necks, such as Plesiosaurus, the group’s poster boy. In actuality, Plesiosaurs contain both the long-necked and large head varieties, and Kronosaurus definitely falls in the latter group.

Named after the Greek Titan Kronos, famous for devouring his offspring, Kronosaurus would have been a similar all-devouring presence, eating everything from its fellow marine reptiles to ammonites, with its large, crushing teeth capable of crushing their hard shells. Its head that yielded its mouth full of daggers accounts for almost one fourth of its predicted overall length.

Kronosaurus’ huge teeth were the fuel of nightmares for the creatures that lived alongside it in Queensland’s Cretaceous waters. These teeth belong to the Harvard Kronosaurus.

Kronosaurus’ huge teeth were the fuel of nightmares for the creatures that lived alongside it in Queensland’s Cretaceous waters. These teeth belong to the Harvard Kronosaurus.

The massive sea monster was named in 1901 after the discovery of a fossilized piece of jaw. It was originally thought to be from a creature in the dolphin-like Ichthyosaur group, before being classified correctly as a pliosaur in 1924. This jaw fragment is the type specimen (first described specimen for a species) of Kronosaurus queenslandicus, and still resides in the collection of the Queensland Museum, in Brisbane. It is a remarkably important fossil, but nowhere near the tremendous skeleton blown out of the Queensland limestone in the early 1930s.

William Schevill was a graduate student at Harvard when he went on a collecting trip to Australia for Harvard’s Museum of Contemporary Zoology (MCZ) in 1931. Giant fossil reptiles could not have been further from Schevill’s mind when he originally set out on the expedition, as the main goal was to simply collect specimens of Australia’s remarkable wildlife that the MCZ was lacking. Most importantly the museum wanted marsupials, from koalas to the “Tasmanian wolf” or thylacine as it was about to go extinct in the next five years. Schevill ended up bringing back perhaps the most iconic specimen in the Museum’s collection.

After most of his group had departed with preserved marsupials, Schevill was alerted by a rancher to something strange sticking out of the ground on his property near Hughenden, Queensland. That something ended up being the bones of the most complete Kronosaurus skeleton ever discovered. But there was the big problem of breaking the bones out of the solid limestone that entombed them. Schevill convinced a British migrant, who was knowledgeable about explosives, to help blast the limestone tomb into large blocks. According to author Nancy Pick writing about the MCZ in the book The Rarest of the Rare, Schevill’s helping hand was nicknamed the maniac because of rumors that he had murdered somebody. Unsurprisingly, he did end up being skilled in explosives and used dynamite to blast out the Kronosaurus skeleton into several large blocks that weighed around six tons each.

Kronosaurus’ story takes a bit of a sad turn here as the remarkable skeleton was shipped around the world to Cambridge, Massachusetts. Paleontology imperialism has become a big issue in recent years with the struggle of Mongolia to keep its incredible fossils within its borders and to this day some in Australia must feel dismayed that the most iconic skeleton of Kronosaurus resides in Boston at one of the world’s most renowned universities. For a while, paleontologists in Australia were left only with the jaw fragment as the best specimen was shipped to the Ivy League.

On the other side of the world, Kronosaurus sat in the large limestone blocks gathering dust far away from its home for decades. The skull, with its menacing teeth and great size, was prepared right away while the skeleton lingered in stone. It may still be there if a local businessman interested in sea monsters didn’t offer the museum $10,000 to complete the skeleton restoration. Scientists then reconstructed and displayed the skeleton using the actual bones and plaster to fill in the missing pieces. Plaster accounts for a third of the display.

The Kronosaurus skeleton looms behind the Triceratops skull in the Romer Hall of Vertebrate Paleontology at the Harvard Museum of Natural History.

The Kronosaurus skeleton looms behind the Triceratops skull in the Romer Hall of Vertebrate Paleontology at the Harvard Museum of Natural History.

As with every restoration of a prehistoric creature, the Harvard Kronosaurus is not 100 percent accurate. The skeleton was missing a large part of its backbone, which led to the reconstruction team probably adding in too many vertebrae, making the displayed creature too long at 42 feet. Paleontologists today think the creature was closer to 30 feet in real life.

The fact that the Harvard Kronosaurus is encased in plaster and on the museum’s wall makes re-examining the specimen difficult. Scientist’s have nicknamed it “Plasterosaurus.” Australian scientists have clamored for the specimen to be freed from its plaster encasing and re-examined along with more recent partial finds from Queensland to get a better understanding of what the creature actually looked like and where it should sit in the marine reptile family tree. But the iconic Harvard Kronosaurus is still exhibited with its huge mouth agape along with possibly 8 extra vertebrae. Ironically, while being at the museum made Kronosaurus much more well known to paleontology fans around the world, it is now making it more unknown to the scientists who want to study it.

I have been able to see this magnificent specimen twice in person and was taken aback by its size both times. It is hard to even fit it in one camera shot when you are looking right at it and its huge head makes it obvious why the species has become such a hit at the museum. But Queensland is still crazy about Kronosaurus, even if the most famous specimen is 10,000 miles away. Kronosaurus Korner Museum in Richmond, Queensland houses several large marine reptile fossils and takes people out on fossil digs in the surrounding fossil rich area. A full-size replica of its namesake fossil reptile greets visitors outside the museum with its mouth agape, just like its fossil counterpart at Harvard.

Harvard’s Kronosaurus queenslandicus.

Harvard’s Kronosaurus queenslandicus.

All photographs and art by Jack Tamisiea.