"The little tree frog was confined inside a bag of bananas so we asked her to make some tiny air holes in the plastic and add some water for moisture and keep him confined until we could attend," Animal Collection Officer John Greaves said.
"The amphibian must have had quite the shock when he emerged in a Lancashire supermarket considering he's used to more tropical climates usually!" he said.
Greaves took the frog to the Reptilia rescue group in Ossett, where it was identified as a tree frog from the Dominican Republic.
"That means he's definitely a long way from home -- more than 4,200 miles in fact!" Greaves said.
He said Reptilia staff took custody of the exotic amphibian and are helping it recover from its ordeal.
"He's a little skinny following his ordeal but he should make a full recovery," Greaves said.