New Jurassic Dinosaur, The Size of a Dog, Is Discovered in Colorado and Reveals Hidden Diversity of Small Species.
A new small and speedy dinosaur has been identified by scientists in the Morrison Formation, in the state of Colorado, United States. Named Enigmacursor mollyborthwickae, it lived between 150 and 145 million years ago, during the Late Jurassic.
It was the size of a dog, about half a meter tall and just over a meter long.
Agile And Young Herbivore
The Enigmacursor mollyborthwickae was a bipedal herbivorous dinosaur. According to paleontologists Susannah Maidment and Paul Barrett from the Natural History Museum of London, the analyzed skeleton shows signs that the animal was young.
-
Forget the slow sweeper: China creates a vacuum truck that cleans highways at up to 80 km/h, sucking up stones, dust, and metals from the asphalt and promises to reduce blockages without stopping traffic.
-
Why could the melting of ice in Greenland and Antarctica force an unprecedented change in the world’s clocks and alter UTC for the first time in history, delaying a correction that challenges global digital systems?
-
Elon Musk could compromise night sky observation with a $2.4 trillion plan that envisions more than 1 million satellites; simulation indicates up to 14,072 visible objects in São Paulo, and astronomers issue a worrying warning.
-
Airplanes will be ‘made’ by robots: Airbus launches a machine weighing only 4 kg that reduces seat installation time from 150 to 30 minutes, achieves millimetric precision, and is already set to debut in the production of the A321 XLR.
The vertebrae found were not fully fused, indicating that it was still developing.
The species would have moved quickly across floodplains in the western United States, coexisting with giants like the Diplodocus and Stegosaurus.
From Nanosaurus To Enigmacursor
The skeleton was found between 2021 and 2022 in a commercial quarry in Moffat County, Colorado. Initially, researchers thought it was a Nanosaurus, a species described in the 1870s. However, after a more detailed analysis, they concluded that the original fossil of Nanosaurus was poorly preserved and not a reliable reference.
The differences between the new specimen and the old one were sufficient to classify it as a new genus and species. Thus, the name Enigmacursor mollyborthwickae was officially adopted, replacing the old label of Nanosaurus.
New Piece In The Jurassic Puzzle
The discovery increases the known diversity of ornithischian dinosaurs from the Morrison Formation. Researchers highlight that it brings new information about the anatomy of these small herbivores and suggests that they were more varied than previously thought.
“There is additional cryptic diversity of small-bodied ornithischians in the Morrison Formation,” said the authors of the study published in the journal Royal Society Open Science.
This new species, preserved in three dimensions and with some associated teeth, helps scientists better understand the ecosystems of the Jurassic period. It shows that even the smallest dinosaurs have much to reveal about the history of life on Earth.

No Brasil, especialmente na região Nordeste, existem diversos sítios arqueológicos e também paleontológicos com fósseis de diversos tipos, muitos do Pré Cambriano (anterior aos dinossauros) e que corresponde desde a formação do planeta até aproximadamente 550 milhões de anos atrás. O que falta é verba para pesquisas, verba que sobra para aumentar o número de deputados federais (verba de gabinete, assessores, etc).