What started as a normal day at the beach for Philip Mullaly ended with a key scientific discovery.

Mulally found a series of shark teeth dating back 25 million years, belonging to a "mega-tooth" shark believed to be twice as big as a large white.

"I was walking along the beach looking for fossils, I turned and saw this glittering sparkle in a rock and saw a quarter of the exposed tooth" said in a statement Mullaly. "I was immediately excited, it was just perfect and I knew it was an important discovery that had to be shared with people."

Mullaly donated teeth to the Victoria Museums in Australia to preserve as part of their collection.

The museum said that the teeth belonged to an extinct species called Great serrated serrated shark (Carcharocles angustidens), which could reach twice the size of a great white shark.

The shark was among the best predators during its heyday 25 million years ago, feasting mostly on small whales.

"These teeth have international significance, as they represent one of only three associated groups of Carcharocles angustidens teeth in the world, and the very first set to be discovered in Australia," Dr. Erich Fitzgerald, the senior curator of vertebrate paleontology at the Museums Victoria, in a statement.

The New York Times reports that Mullaly found his teeth in 2015. During two expeditions that took place last December In January, Fitzgerald led a team of experts in the place where Mullaly found his teeth to be excavated.

The researchers collected more than 40 shark teeth, including those from a species called the Sixgill shark.

The species, still alive today, probably fed on the remains of the mega-tooth shark after his death.

"This finding suggests that they have interpreted this way of life here for tens of millions of years," said Pale Museum palaeontologist Tim Ziegler.

Teeth went on show Thursday and will remain available to the public until October [19659016] Follow Brett Molina on Twitter: @ brettmolina23 .

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