DENTON - Maggie Jones stares at the fossil sitting at the University of North Texas with caring and confident eyes.
It's her 250-pound discovery that's on display.
"I didn't even dream that we would ever find something like this," the 12-year-old said.
Maggie and her father, Paul, found the fossil two years ago in their Denton backyard while roasting marshmallows.
"We saw a rock sticking out of the bank, so we dug that up and flipped it over, and it was smiling at my dad," Maggie said.
The fossil definitely made UNT Geography professor Dr. George Maxey smile.
"This is just not something that walks in through the door every day," Maxey said.
The professor is also the director of the UNT's Meteorite, Rock, Mineral and Fossil Identification lab. When the Jones family showed it to him, he knew, it was part of the pre-historic predator known as the Xiphactinus, a fast moving fish that was about 15 feet long.
"It's really hard to get used to the idea that you are looking at something that's roughly a hundred million years old, that swam in the ocean slightly to the east of where we are standing," the professor said.
Maxey calls it one of the best fossils he has ever received. He's fascinated with the its condition.
"It's possible that this was a storm event," Maxey told News 8. "A storm may have washed the thing ashore, and it got buried in the muds and that's what allowed the preservation."
Maggie and her dad loaned the fossil to the university for a year. They are proud to share their discovery.
"I know we won't forget about it," Maggie said. "It will stay in our brains forever."
The Xiphactinus will be display on the first floor of the Environmental Education, Science and Technology building.