Found more than 160 years apart, two halves of the same bone has finally allowed a group of scientists to image one of the largest ancient sea turtles to have ever lived.

According to BBC News, the first half of the broken arm bone, also called a humerus, was found in New Jersey in the 1840s. The second half was found in the same state in Monmouth County.

Based on the now-complete bone, the Drexel University team estimated the ancient sea turtled, named Atlantochelys mortoni, three meters long from nose tip to tail end.

"As soon as those two halves came together, like puzzle pieces, you knew it," Dr. Ted Daeschler, of the Academy of Natural Sciences of Drexel University, said in a press release.

Gregory Harpel, an amateur paleontologist from Oreland, Pa., was visiting Monmouth County to practice his weekend hobby of fossil hunting in a brook. On a grassy bank of the brook he noticed the bone and thought it looked awfully out of place.

Harpel paseed the bone on to Jason Schein, assistant curator of natural history at the New Jersey State Museum, who then brought it to the academy. Another curator, David Parris, jokingly suggested the bone, which recognized as a humerus, was the missing half of the one found in the 1840s. To both curators' astonishment, it was the missing piece.

"I didn't think there was any chance in the world they would actually fit," Schein said in the release.

The researchers have published their work in the upcoming edition of the journal Proceedings of the Academy of Natural Sciences of Philadelphia. The discovery is also featured in the current issue of National Geographic.

Daeschler said A. mortoni looked similar to the modern sea turtle, except way larger.

"This turtle was a monster, probably the maximum size you can have for a turtle," Daeschler told BBC News. "Scientifically, we now know a lot more about this creature.

"Most importantly, we now know precisely which rock formation the original came out of, and so we can more precisely know its age, and we can be much more confident about finding additional material in that same formation and therefore telling more about A. mortoni."