A speedy little dinosaur from Colorado has officially joined the family of prehistoric creatures. Named Enigmacursor mollyborthwickae, this new species measures about three feet long and is now showcased at London’s Natural History Museum.
Experts believe this fossil sheds light on long-standing confusions among small plant-eating dinosaurs from the American West. The discovery helps clarify details about these tiny creatures, previously grouped under vague names, especially Nanosaurus.
In a study led by Professor Susannah Maidment at the Natural History Museum, researchers classified Enigmacursor within the neornithischians, a group of early plant-eaters. These two-legged herbivores often got overlooked in past research. The structure of Enigmacursor’s legs, especially its femur and shin, indicates it was quite a runner, hinting at its agility in avoiding predators.
For over a century, many small dinosaurs were crammed into catch-all categories, making it tough for scientists to pinpoint what they were. A 2025 review found that many historic names were based on incomplete fossils, leading to confusion. Enigmacursor, with its complete skeleton, provides clearer data for future studies.
This dinosaur lived in the Morrison Formation, a region known for its rich fossil record from the Late Jurassic period. It thrived in ecosystems filled with enormous sauropods and sharp-toothed predators. This small herbivore likely relied on speed and alertness to survive in such a perilous environment.
What’s fascinating is how Enigmacursor was found. Collected from private land in Colorado, it was later purchased by the museum and digitally scanned. These scans allow scientists worldwide to study this dinosaur without risking damage to the original bone.
Interestingly, small dinosaurs like Enigmacursor often don’t get much attention. Their fragile bones are easily overlooked, and larger fossils tend to attract more collectors. Professor Maidment notes that many small species probably remain undiscovered.
The clean classification of Enigmacursor doesn’t just tidy up scientific names; it impacts ecological and evolutionary studies. Researchers can understand species diversity and interactions better when names are secure. This newfound clarity suggests that the small herbivores of the Morrison Formation were more varied than previously thought, paving the way for further discoveries.
These advancements in research highlight the importance of digitizing fossils. By creating detailed 3D models, paleontologists can easily share and analyze fossils globally, opening up avenues for identifying new species and studying their evolution.
Small herbivores like Enigmacursor are crucial to understanding prehistoric ecosystems. They grazed on low plants, dispersed seeds, and served as food for larger predators. Their role in these environments is reshaping how we view the dynamics of the Jurassic landscape, which is no longer just a stage for giants but a vibrant web of interactions and diversity.
For more insights into these discoveries, you can read the detailed study in Royal Society Open Science here.
