A Fort Pierce, Fla. dock fisherman found an unexpected catch on the end of his line when he reeled in an 18-inch crustacean that was striking at its own tail and had to be handled from its backside like a lobster.

Florida Fish and Wildlife Conservation Commission officials said in a Facebook posting that the creature is thought to be a mantis shrimp, although the exact species of which has yet to be determined.

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They're "actually not related to shrimp but are a type of crustacean called a stomatopod," the commission wrote. Scientists, they noted, are reviewing the pictures taken by the fisherman, in order to nail down the species of mantis shrimp, of which there are some 400.

Luckily for the enormous shrimp, the fisherman released it back into the water after taking his pictures.