Fishermen caught a hammerhead shark with a huge section missing from its body after apparently being bitten by a mysterious sea beast.
The large deep semicircular bite exposed raw muscle, flesh and internal organs.
Footage showed the hammerhead, which weighed around 551lbs (250kg), lying motionless on the harbour side with around half its body missing.
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Fishermen came across the dead shark during a routine outing off the coast of Celestún in Yucatán State, Mexico, yesterday (28 Jul).
The shocking video spread rapidly across social media and sparked a wave of wild theories, as reported by Need To Know.
Viewers were left stunned by the sheer size of the injury on such a powerful animal.
Many social media users claimed it was caused by a megalodon, a prehistoric giant shark long thought extinct.
Others insisted a killer whale must have administered the fatal bite.
But marine biologists quickly dismissed both ideas as impossible.
Megalodons died out more than three million years ago and no longer roam any ocean.
And orcas do not inhabit the depths around the Yucatán Peninsula.
Experts instead point to a larger modern shark as the most likely culprit.
Tiger sharks or great whites possess the powerful jaws and sharp teeth needed to inflict such damage in a single bite.
These apex predators are known to attack weaker or trapped hammerheads when the opportunity arises.
Another plausible theory suggests the hammerhead may have become snagged on a commercial fishing line first.
The distress signals and vibrations it sent out would have drawn in opportunistic hunters.
The wound’s shape and depth match known cases of shark-on-shark predation in open waters.
No official statement has yet come from environmental authorities or marine specialists.
Shark experts stress that cannibalism and inter-species attacks form a normal part of marine life.
But human fishing pressures and the demand for fins remain a greater long-term threat to hammerhead populations in the Mexican Caribbean.
Hammerheads are protected in Mexican waters.
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