Giant dinosaur skeleton discovered in US state: ‘Extremely unusual’ 30-foot Cretaceous-era monster nearly intact in ‘rare’ find dating back 80 million years

The most complete dinosaur fossil ever discovered in Mississippi, called “highly unusual” by state officials, remains 85 percent buried since its discovery in 2007.

Paleontologists have confirmed that the specimen was once a living hadrosaur: a family of vegetarian, duck-billed dinosaurs that existed over 82 million years ago.

But the hadrosaur is a large family of giant herbivores – including at least 61 individual identified species, with perhaps hundreds of unique species that once roamed the Earth, according to experts.

Researchers have secured parts of the specimen’s vertebrae, parts of the forearm, legs and pelvic bones, but the rest has proven tricky to unearth from its location outside Booneville in the northeastern part of the state.

“This thing sat for a while because we didn’t have anybody to work on it,” as a state geology office official, James Starnes, recounted.

Hadrosaurs are a large family of giant plant-eating dinosaurs – including at least 61 identified, individual species with perhaps hundreds of unique species that roamed the Earth, according to experts. The hadrosaurs above are an artist’s reconstruction of a Russian find

The most complete dinosaur fossil ever discovered in Mississippi is now known to be from the hadrosaur family – but only 15 percent of it has been safely identified. Researcher Derek Hoffman (above) is turning to 3D forensic analysis of bones to reveal the exact species of hadrosaur

For nearly two decades, it has remained a mystery exactly which of the many types of hadrosaur was actually the type unearthed in this Booneville, Mississippi-area find.

But researchers are now turning to a 3D method of forensic bone analysis to solve the puzzle before it is fully revealed.

University of Southern Mississippi (USM) geology graduate student Derek Hoffman is now analyzing hadrosaur remains with this method, known in many scientific disciplines as “geometric morphometrics.”

“What geometric morphometrics does,” as Hoffman put it simply, “is take a shape analysis approach.”

Key features or ‘landmarks’ are determined for a given bone sample and their corresponding distances, and ratios of those distances, are then compared via complex statistical models to confirm differences and similarities with known bones.

The method has also proven effective in anthropology as well as studies of human evolution, including comparisons between the brain cavities of modern humans and our Neanderthal ancestors.

But Hoffman’s hunt for answers about this hadrosaur fossil has been made more difficult by the fact that some parts of the creature are in the hands of private collectors.

Above, the upper arm bone of an ancient hadrosaur discovered in northeast Mississippi

Hoffman’s work focuses primarily on bones held publicly by the Mississippi Museum of Natural Science.

“We have quite a few vertebrae,” the museum’s curator of paleontology, George Phillips, told the local Clarion Ledger newspaper. “We have a humerus.”

‘We have an ulna. The ulna is the back of the forearm.’

“We have some of the leg bones,” Phillips continued. ‘Then we have pubis’.

The ulna of the adult hadrosaur comes to about two feet long and the humerus bone is in the range of about a foot and a half long. And just one complete leg bone of an adult hadrosaur could exceed 50 pounds in total weight.

But the dinosaur’s skull — the most unique identifying feature for distinguishing hadrosaur species — must disappoint researchers that it has yet to be found.

Different species of hadrosaurs are well known to have evolved a wide and strange variety of crowns on their duck heads, even bare materials like red rooster ‘combs’.

Paleontologists are still debating what biological purpose these unusual and sometimes conspicuous features may have served, but their variety has contributed to the recorded diversity of the hadrosaur family.

Hoffman at USM has focused on the dinosaur’s pubis, a bone from the front of the pelvis, as the next best bet for identifying the species of this fossil.

While the differences between the pubic bones of hadrosaur species are subtle, often too subtle to the naked human eye, their hidden differences can be teased out by rigorous mathematical approaches such as geometric morphometrics.

The USM geology graduate student hopes to at least narrow down the number of possible hadrosaur species this Mississippi fossil could be.

Or: ‘What is the lowest taxonomic level we can get this hadrosaur to,’ as Hoffman put it.

What is now known about this particular hadrosaur is that it was likely about 25-26 feet long and was about 16 feet tall when sitting on its hind legs.

Hadrosaurs as a family of species are ‘the most represented dinosaurs in the fossil record’, according to Hoffman, ‘without doubt’. Pictured: an artist’s impression of another duck-billed dinosaur in the group, an 80-million-year-old one discovered nearby in Texas

While researchers believe that hadrosaurs originated in North America, the plant-eaters migrated across the globe with fossils discovered in Asia, South America, Europe and North Africa.

“They are the most represented dinosaurs in the fossil record,” Hoffman said, “without a doubt.”

The name Hadrosaurs is derived from the ancient Greek for ‘strong lizard’, and the heavy animals actually ranged from about 2.2 to 4.4 US tons (or between 2000 to 4000 kilograms).

Many hadrosaur species lived between 75 and 65 million years ago in the Late Cretaceous period.

Other examples of dinosaurs from the hadrosaur family include Parasaurolophuswhich had a long, swept-back crest on its head and appears in the 2022 film Jurassic World Dominion, and Edmontosauruswhich had the aforementioned crest made of soft tissue like a rooster.

State official James Starnes, with the Mississippi Department of Environmental Quality’s Office of Geology, said the discovery of this hadrosaur in 2007 near Booneville was just ‘very unusual.’

“We just don’t have a lot of skeletons,” Starnes said. “We have bits and pieces, but not a skeleton.”

Starnes hopes that, despite the nearly two decades it took him to uncover just one part of this hadrosaur fossil, that the project will one day be completed.

“We’re still getting more out of this specimen,” Starnes said.