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Scientists have discovered a new species of dinosaur — one that was dog-sized and roamed what is now the United States around 150 million years ago alongside familiar dinosaurs like stegosaurus and diplodocus.

The Enigmacursor mollyborthwickae, as researchers named it, was about the same size as a Labrador retriever, with a tail that made up about half of its length, according to a study published in the Royal Society Open Science on Wednesday.

Although many of its bones were unearthed from the Morrison Formation in Colorado in 2021-2022, its skull and parts of its vertebral column were missing, leaving scientists unsure of its precise length.

“These very small plant-eating dinosaurs are pretty rare (to find),” Professor Paul Barrett, a researcher at London’s Natural History Museum who co-led the study, told CNN.