An 8-year-old boy made a prehistoric discovery this month by finding a giant tooth believed to be from the long-extinct angustidens – a megatooth shark species.

Riley Gracely of Pennsylvania discovered the massive tooth during a family vacation to Myrtle Beach, South Carolina.

According to Palmetto Fossil Excursions (PFE), the boy discovered a 4.75-inch tooth belonging to the extinct shark Carcharocles angustidens while participating in a fossil-hunting excursion near Summerville.

“Truly the find of a lifetime,” PFE wrote in an Aug. 11 Facebook post. “This young man just scored a 4.75″ Angustiden tooth in our Premium Gravel Layer piles on a dry dig!!!”

“Just to give perspective — any [angustidens] over 4″ is the equivalent of finding a 6″ [megalodon], and an [angustidens] at 4.75″ is the equivalent of finding a 6.5″ megalodon tooth,” the group wrote.

On Monday, the boy’s find continued to draw hundreds of likes and dozens of comments on Facebook.

“Meet a future paleontologist! Good job, young man!” one user wrote.

“Wow, that is one amazing fossil! Congratulations!” Matthew Migel posted.

Riley Gracely’s dad Justin Gracely told Fox News his son is an avid fisherman who loves science and the outdoors. 

“We vacation in Myrtle Beach every summer, so from the time that Riley and his brother Collin could walk, we’ve been into searching for these treasures on the beach,” he told the outlet.

“(Riley’s) collection is still in its early stages, so he’s keeping it for now, but who knows in time. It would be nice for others to enjoy it, too.”

Natalie Neysa Alund covers trending news for USA TODAY. Reach her at nalund@usatoday.com and follow her on Twitter @nataliealund.