“I had to cut my dive short because I could not catch my breath after snatching it up.”

Michael Nastasio was exploring the ocean floor off Venice, Florida, last week when he came across something that made him cut his dive short.

Captain Mike, as he prefers to be called, is captain and owner of Black Gold Fossil Charters. He has been an aquatic fossil hunter for nine years, but this time he hit the jackpot.

Nastasio told WFLA that he was about to take his three customers back to shore, when they asked him to make one more dive.

That's when he found a truly massive shark tooth.

"It took a minute to even register that it was real, just because when you are looking at stuff through your goggles it makes everything look bigger underwater, so seeing that size tooth exposed as it just absolutely took my breath away," Nastasio told the station.

He shared photos of what appears to be a Megalodon tooth on Facebook.

"Check out this BEAST of a tooth! I recovered it yesterday in Venice. It measures just over 5 7/8 but not quite 5 15/16," he wrote alongside the impressive snaps. "I had to cut my dive short because I could not catch my breath after snatching it up."

There's a reason Venice is often referred to as the "shark tooth capital of the world." Ten million years ago, the area was underwater and teeming with sharks. The seas receded over time, causing the prehistoric sharks to die. And while their skeletons disintegrated, their fossilized teeth remained, according to VisitSarasota.com.

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The Venice coastal area sits on top of a fossil layer that runs 18-35 feet deep. Storms slowly drive the fossils into the shallow waters and then up onto the beach.

"If it blows hard enough out there it rips into the bottom, it throws material everywhere and that is how this stuff gets uncovered and exposed," Nastasio explained to WFLA. "I won't go back to that spot now until we get another storm because every time the storm goes through it returns the bottom and [exposes] new stuff."

Pretty cool!