Authorities say a gardener in the state’s Pasco County spotted what was later confirmed to be a giant African land snail on Tuesday, sending a small area into quarantine.
No African land snails, yard waste, debris, compost or building materials can be removed from the area without permission of state authorities.
The snails have been described as “one of the most invasive species on the planet” by Florida’s wildlife department because it can feast on 500 types of crop and lay thousands of eggs at a time.
The snails also carry a virus known as rat lungworm, which can cause meningitis in humans and so is considered a “serious health risk”.
People are advised not to touch one of the gigantic snails with their bare hands and to wear gloves to avoid contamination.
The Florida’s Department of Agriculture and Consumer Services (FDACS) said the quarantine order would come along with the use of a pesticide known as “snail bait”, with that treatment beginning on Wednesday.
Giant African land snails have been eradicated twice before in Florida. The state only declared last year that the species had finally been eradicated following a sighting in 2011 in Miami Dade County.
The detection of a snail in 1969, meanwhile, saw the species eradicated by 1975.
Importing or possessing the snail is already illegal in the US. It is known to feed on crops including “peanuts, beans, peas, cucumbers and melons”, the US agriculture department says.