Back in November, 9-year-old Jude Sparks was hiking with his family in New Mexico’s Las Cruces desert when he tripped over something and fell. Jude’s face landed next to what appeared to be a massive jawbone. Then he looked up and spotted a tusk.

As Jacey Fortin reports for the New York Times, Jude, now 10, had accidentally stumbled upon the fossilized skull of a 1.2 million-year-old stegomastodon, an extinct proboscidean that belongs to the same family as elephants, mammoths and mastodons. But at the time, Jude wasn’t quite sure what he had found.

“It was just an odd shape,” he tells Fortin. “I just knew it was not something that you usually find.”

Jude’s family put forth some guesses about the remains—his younger brother thought Jude had discovered a cow’s skull, while his parents speculated that the bones belonged to an elephant—but they soon decided to consult with Peter Houde, a biology professor at New Mexico State University.

According to an NMSU press release, the family had seen Houde interviewed in a YouTube video about a similar fossil found near the university’s campus. And when he saw the Sparks' picture of the remains, Houde knew almost immediately that they belonged to a stegomastodon.

The ancient creatures, which may have been hunted by early humans, were one of three species of Pleistocene that roamed through the Rio Grande Valley during the Pleistocene, the time period that spanned 2.6 million to 11,700 years ago. Though the latest find is likely one of the more common species of stegomastadon, it's still rare, House explains in the press release. "This may be only the second complete skull found in New Mexico,” he says.

After Houde was alerted to the discovery, the stegomastodon’s jaw and two pieces of tusk were transported to the Vertebrate Museum at NMSU. The remainder of the skull, which weighs approximately one ton, was excavated in May. The painstaking process of reconstructing the fossil will not be completed for years, but Houde hopes that the skull will one day go on display.

“I have every hope and expectation that this specimen will ultimately end up on exhibit and this little boy will be able to show his friends and even his own children, look what I found right here in Las Cruces,” he says

And as for Jude, the discovery has rekindled his interest in dinosaurs and fossils—a subject that fascinated him in his (relatively) younger days, between the ages of 5 and 8. “I’m not really an expert,” Jude tells Fortin of the Times, “but I know a lot about it, I guess.”

Jude certainly has more paleontological experience than most 10-year-olds. According to the NMSU press release, the boy and his family were on hand during the excavation, watching as the ancient fossil was brought to light.