Paleontologists in Argentina have announced a remarkable discovery: a new carnivorous dinosaur preserved with a crocodile bone lodged in its mouth. This rare fossil snapshot offers a direct window into the dinosaur’s last meal—or at least its final moments—providing unusually clear evidence of diet and behavior in the deep past.
The find comes from Patagonia, one of the world’s richest regions for dinosaur fossils. Researchers say the preserved crocodile bone—likely from a crocodyliform, the broader group that includes ancient crocodile relatives—was wedged between the dinosaur’s teeth when it was buried. Such “caught-in-the-act” fossils are exceptionally rare and give scientists new clues about predator-prey interactions in the Cretaceous ecosystems of South America.
Key points
- New dinosaur fossil discovered in Patagonia, Argentina
- Crocodile bone preserved between the dinosaur’s teeth
- Offers rare, direct evidence of feeding behavior
- Improves understanding of ancient food webs and ecosystems
- Team used modern imaging and careful lab analysis
What exactly did scientists find?
The specimen includes parts of the dinosaur’s skull with teeth intact. Between those teeth, researchers identified a crocodile bone fragment, most likely from a small crocodyliform that lived alongside the dinosaur. The bone appears to be trapped in a way that suggests the dinosaur had been biting or tugging at crocodile flesh. While stomach contents are occasionally preserved in fossils, finding a prey animal’s bone stuck between a predator’s teeth is much rarer and can be even more informative about immediate behavior.
The team carefully examined tooth marks, bone texture, and the fit of the fragment to confirm it belonged to a crocodile relative rather than another dinosaur or unrelated animal. Details like the bone’s ridges and density, along with comparisons to known crocodyliform fossils from the region, helped clinch the identification.
How did a crocodile bone end up in a dinosaur’s mouth?
There are three main possibilities:
- Mid-meal moment: The dinosaur may have been feeding on a crocodile when it died suddenly—perhaps in a flood or a collapse of sediment—locking the scene in time.
- Scavenging: The dinosaur might have been scavenging a crocodile carcass rather than hunting a live animal.
- Post-mortem shift: It’s always possible the fragment drifted into the mouth after death. However, the way the piece is wedged between the teeth can argue against this, making active feeding more likely.
Regardless of the exact scenario, the fossil preserves direct evidence of interaction between these animals—an invaluable data point for reconstructing ancient food webs.
Why this matters for science
Most of what we know about dinosaur diets comes from indirect clues like tooth shape, jaw mechanics, and bite marks on bones found nearby. Direct evidence—such as preserved stomach contents, coprolites (fossilized droppings), or prey bones lodged in the mouth—is far less common. Finds like this one help scientists move beyond educated guesses and into clearer reconstructions of behavior.
In Patagonia, crocodile relatives were diverse and abundant during the Cretaceous. The new fossil reinforces the idea that carnivorous dinosaurs shared rivers, floodplains, and lakes with a wide range of crocodyliforms—and sometimes preyed on them. It also points to a dynamic, competitive ecosystem where multiple large predators and opportunistic scavengers overlapped.
What kind of dinosaur is it?
The fossil belongs to a carnivorous theropod—the broad group that includes famous meat-eaters like Tyrannosaurus and the South American abelisaurids. While the specimen is new to science, it fits the picture of agile predators that roamed Patagonia late in the Age of Dinosaurs. Scientists are analyzing anatomical details of the skull, teeth, and other bones to determine exactly where it sits on the dinosaur family tree. Those features will help confirm its closest relatives and refine its official classification.
How the team studied the fossil
Researchers combined careful field documentation with laboratory imaging. High-resolution photography and, where possible, CT scanning helped visualize how the crocodile bone fits among the teeth without damaging the fossil. Microscopic inspection of tooth wear and bone surface texture can reveal whether the fragment was bitten, pulled, or crushed, and whether marks line up with the dinosaur’s tooth shape and bite forces.
The fossils were also compared to a large reference collection of crocodyliform bones from the region. Subtle traits—such as the shape of ridges, joint surfaces, and internal bone structure—supported the identification. The result is a stronger case for direct feeding evidence, rather than a chance association.
A window into Patagonia’s Cretaceous world
Patagonia’s ancient landscapes were a patchwork of rivers, lakes, and floodplains. Along these waterways lived herds of plant-eating dinosaurs, packs of small predators, and numerous crocodile relatives—from sleek fish-eaters to heavily armored ambush hunters. The new fossil shows that interactions between dinosaurs and crocodyliforms were not just possible but real and sometimes deadly.
This kind of direct evidence helps researchers test bigger ideas: How did predators divide resources? Did they specialize on certain prey, or take whatever they could find? Were crocodile relatives frequent targets, or occasional meals? Each new “behavioral snapshot” nudges the answers forward.
What happens next
The team plans additional analyses and comparisons with other Patagonian theropods to refine the dinosaur’s identity. More fieldwork at the site may uncover additional bones from the same animal—or even remains of the crocodile itself. If more of the skeleton turns up, scientists could estimate body size and strength, and better understand how this predator hunted, fed, and moved.
As the scientific paper and technical descriptions become available, museum exhibits and outreach programs will likely follow. That means the public will get a closer look at a dramatic moment from prehistory: a dinosaur, frozen in time, with a crocodile bone caught between its teeth.
Frequently asked questions
What makes this fossil so special?
It’s rare, direct evidence of feeding. Instead of guessing from tooth shape or bite marks, we see a crocodile bone physically lodged between the dinosaur’s teeth, capturing behavior at or near the moment of death.
How old is the fossil?
The fossil comes from Cretaceous-age rocks in Patagonia. That places it tens of millions of years ago, in a time when dinosaurs and diverse crocodile relatives lived side by side in river and lake environments.
Did the dinosaur hunt the crocodile or scavenge it?
Both are possible. The way the bone is trapped between the teeth supports active feeding, but the fossil record can’t always tell whether the crocodile was killed or already dead when the dinosaur fed on it.
What kind of crocodile was it?
The fragment belongs to a crocodyliform—an extinct relative of today’s crocodiles and alligators. Patagonia hosted several types, from small terrestrial forms to semi-aquatic ambushers, so further study will aim to narrow down which group it came from.
What kind of dinosaur is it?
It’s a carnivorous theropod. Researchers are analyzing skull and tooth features to determine its closest relatives and to formally describe and name the species in the scientific literature.
Where will the fossil be kept?
Newly described fossils from Argentina are typically curated in regional museums or research institutions so they can be preserved, studied, and displayed. Details will be shared as the study progresses.
Why is direct evidence of diet so rare?
Soft tissues and feeding moments are rarely preserved. Most fossils are scattered bones. Capturing a predator with prey remains in its mouth demands unusually fast burial and very specific conditions—one reason this find is so exciting.
What’s next for research on this specimen?
Continued imaging, detailed comparisons, and additional fieldwork. If more bones are found, scientists can better estimate size, growth, and behavior, and confirm how common dinosaur–crocodile interactions were in this region.
With every new discovery, Patagonia continues to reveal how complex and competitive life was at the end of the Age of Dinosaurs. This fossil adds a vivid, tangible scene to that story: a dinosaur, jaws clenched, with the telltale bone of a crocodile caught between its teeth.
