Exciting news for dinosaur enthusiasts! The Natural History Museum (NHM) in London is set to unveil a remarkable new addition to its world-leading collection: Enigmacursor mollyborthwickae. This captivating creature, roughly the size of a Labrador dog, represents a newly identified species that is unlocking secrets about the lives of smaller dinosaurs that roamed the Earth alongside famous giants.
This significant debut marks the first time the NHM has put a newly named dinosaur species on public display since 2014. Enigmacursor, meaning “puzzling runner,” offers a rare and crucial glimpse into the Late Jurassic period, approximately 150 million years ago.
A Case of Mistaken Identity
When the fossil specimen was first discovered in the Morrison Formation of the Western United States, it was mistakenly categorized as a Nanosaurus. Nanosaurus was a broad classification often applied to small dinosaurs found since the 1870s. However, scientists at the NHM grew suspicious that this particular specimen was something different.
Paleontologists, including Professor Susannah Maidment, undertook meticulous research. They noted unique features in the skeleton, particularly in the leg bones. To confirm their suspicions, they traveled to the US to examine the original Nanosaurus archetype specimen. This proved challenging, as that original fossil was incomplete – essentially just rock with bone impressions.
In stark contrast, the NHM’s specimen is a sophisticated, nearly complete skeleton. Described as the most complete fossil of its kind found anywhere in the world for an early small dinosaur, its unique anatomy provided the definitive clues needed to identify it as a distinct species. This discovery is so impactful that scientists have formally declared the old Nanosaurus category invalid, believing other specimens previously assigned to it are likely also unique species awaiting proper identification.
As Professor Maidment emphasizes, correcting these classifications is “absolutely foundational” to paleontology, ensuring a true understanding of dinosaur diversity.
Meeting the ‘Puzzling Runner’
At 64 cm tall and 180 cm long, Enigmacursor was small by dinosaur standards but packed some interesting features. It possessed notably large feet and a tail that was probably longer than the rest of its body. While its head was relatively small – perhaps suggesting it “was probably not the brightest,” according to Professor Maidment – its solid, dense hips indicate it was built for speed, living up to its name.
Evidence from its smaller front arms, which didn’t reach the ground, suggests they might have been used like hands to shovel plants into its mouth. Scientists believe the fossil specimen was a teenager at the time of its death. It shared its world with massive herbivores like Stegosaurus, whose remains are also found in the Morrison Formation – highlighting the vast size differences in this ancient ecosystem.
Why Small Dinosaurs Matter
While giant skeletons often steal the spotlight, specimens like Enigmacursor are vital for understanding the full story of dinosaur evolution. Professor Paul Barrett, a palaeontologist at the museum, explains that small early dinosaurs like Enigmacursor are “very close to the origins of the large groups of dinosaurs” that evolved later.
They act as crucial puzzle pieces, helping scientists understand how gradual changes occurred over time and identifying the environmental pressures that eventually led to the evolution of the larger, sometimes “bizarre,” descendant forms. Studying these creatures helps fill critical gaps in the fossil record.
A Busy Year for Discoveries
The identification of Enigmacursor is part of a continuously active period for paleontology worldwide. Each year brings dozens of new finds, from potential relatives of Tyrannosaurus rex to intriguing flying reptiles and species offering insights into prehistoric behavior.
For example, recent discoveries include Fona herzogae, another dog-sized dinosaur from the later Cretaceous period in Utah. Fona, unlike the speedy Enigmacursor, shows anatomical and preservation evidence suggesting it may have been a burrower, living at least partly underground. These varied discoveries underscore the immense and sometimes surprising diversity of dinosaur life and the different ecological niches they occupied.
See Enigmacursor in London
After meticulous work by conservators to assemble its delicate bones onto a display frame, Enigmacursor mollyborthwickae is ready for its public debut. It will be housed in a specially designed glass case on a balcony in the NHM’s impressive Earth Hall, fittingly positioned above the skeleton of Sophie the Stegosaurus, one of the ancient giants it lived alongside.
This remarkable new species is a testament to the ongoing work of scientists who continue to piece together the complex tapestry of prehistoric life, often by examining specimens that were previously overlooked. The findings on Enigmacursor mollyborthwickae have been published in the journal Royal Society Open Science. Scientists hope this discovery encourages others to “keep their eyes close to the ground” when searching for fossils, as these smaller finds hold disproportionately large significance for our understanding of the dinosaur world.
