Paleontologist Denver Fowler, Dickinson Museum Center, is readying for summer field work at Montana's Judith River Formation, calling the site "the most exciting I've ever found."
The site already has yielded a new species of nodosaur, belonging to the armored ankylosaur family. It is a low, stocky animal with many side spikes.
A portion of skull and fragments of its arm are being cleaned at the museum center.
"The interesting thing is more that it fills in a gap," Fowler said. "This one we're saying it's a new species because it's about 2 million years older than the next one that's been found for its particular group."
He added, "This is a really awesome specimen."
Fowler also has found a mummified arm of an unidentified duckbill species, still connected at the joints and with preserved skin and exposed bone.
"This was originally in the cliff in a nice big sandstone layer, but it fell out of the cliff and broke up into lots of pieces, most of which have been buried in modern soil," he said. "We'll dig all the soil away and hopefully find more of these blocks."
In one bone bed, 150 feet long, Fowler has found dozens of duckbill dinosaur skeletons. From it, a complete articulated neck was claimed.
"It's full of dead dinosaurs," he said. "It's quite amazing."
Fowler also has three tyrannosaur sites, including one with an especially articulated find.
"All we can see right now are the feet sticking out of the cliff," he said. "This foot has the ankle attached and the lower leg bone going in."
The feet, Fowler said, are placed anatomically correct, pointing toward each other with both in the right place and articulated.
Fowler said he is excited to return to Judith River this July to continue his work.
"We look for new sites one year, and we find a few new sites. We do little digs, but we don't do a big dig," he said. "The big dig comes the following year, because you usually have to get permits and stuff like that."
The site in Montana is "pretty much literally the ancient coast line."
"We actually have all sorts of burrows of estuary worms, things like that, just below where we find the dinosaur bones," Fowler said. "These are animals that were living way out in the delta and periodically the sea level would rise."
The priority for Fowler and his team this summer is recovering the rest of the ankylosaur.
"We got most of the leg bones, the head, some parts of the pelvis and lot of neck spikes this year," he said. "From the back of the quarry, we hope to get lots more armor."
Robert Fuhrman, museum director, lauded the efforts of Fowler and the paleontology lab.
"Dr. Fowler's excitement is pretty infectious. I'm pretty jazzed about it," he said. "When somebody like Dr. Fowler says the one site is probably the most promising he's seen, ever, in his career, it gets the heart moving a little faster."
For more information on Dickinson Museum Center and its dinosaur exhibits, visit " target="_blank">dickinsonmuseumcenter.com/.