Story highlights A man and woman brought a snake, thought to be a boa constrictor, into a Missouri restaurant

Man insists snake is a "service animal," but the law is clear: Only dogs qualify

(CNN) Snake wasn't on the menu of a Missouri restaurant, but that's what patrons got -- along with a side of rattled nerves.

A reptile, thought to be a boa constrictor, was brought into an eatery in Nixa, Missouri, this week, sending some fleeing.

Lisa Loeffelholz told CNN affiliate KYTV that she spotted a man and a woman holding the snake and "it started to slither down into the booth behind her."

Loeffelholz said she notified the restaurant manager -- who said the couple insisted the snake was a service animal and the restaurant should allow it to stay.

But just the sight of the woman apparently pulling the animal and then handing it over to the man at the table was enough to make Loeffelholz confront the snake handlers about their slippery excuse.

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