"What I did was wrong, and I failed to appreciate the gravity of what I have done," Prokopi admitted to U.S. district judge Alvin Hellerstein at a federal court in Manhattan.
Authorities uncovered Prokopi's illegal activities after two paleontologists alerted them to a suspicious auction -- the sale of an apparent Tarbosaurus bataar skeleton. As it turned out, Prokopi had dug up a number dino skeletons in the Gobi Desert in Mongolia.
After bringing the bones home to the states, Prokopi assembled the Tarbosaurus bataar, a relative of T. rex, and put the 8-foot-high, 24-foot-long dinosaur up for sale at Heritage Auctions in New York.
The 70 million-year-old dinosaur was sold for $1 million, but after authorities uncovered its illegal origins, the sale was annulled and the skeleton was returned to Mongolia.
"Heritage Auctions fully cooperated with U.S. and Mongolian authorities to safeguard the fossils pending the outcome of their investigation in this case," Noah Fleisher, a spokesman for the company, told the New York Times. "We hope that Mr. Prokopi's sentence will send a strong message that this abhorrent practice will not be tolerated."
The 39-year-old Prokopi had previously lived and operated out of Gainesville, Florida, but recently relocated to Williamsburg, Virginia. Soon, Prokopi will have a new home: federal prison. Prokopi was also forced to relinquish several other skeletons collected in Mongolia -- reportedly worth more than $200,000 -- and will serve a 15-month probation period after his release.