An American tourist to Greece happened upon an octopus with six legs, also known as a "hexapus." Then he smashed it against a rock and ate it. Only later did he realize that the so-called hexapus is very rare, and that this was only the second six-legged octopus ever found, according to news reports.

The man, Labros Hydras, a mechanical engineer from Washington, D.C., told The Telegraph that in past visits to the country he'd eaten (eight-legged) octopus without feeling guilty, since it's a local tradition. But a call to a biologist friend of his alerted him to the rarity of his ill-chosen meal. Now he wants to make scientists aware of this animal (which he ate with a slice of tomato, lemon and salad). "It is the least that I can do given my ignorance and guilt that I feel for killing such a rare animal," he said.

Octopus can end up with six legs due to developmental abnormalities, and are not thought to be a new species, marine biologist Matt Bentley told the Telegraph. It's possible the creature could have also been injured and healed over time, he said.

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