The highly invasive New Guinea flatworm, which is on the 100 worst invasive species list, has just been found in the United States. Tracked by researchers from the Sorbonne’s National Museum of Natural History, the creature has wormed its way from typical island locations to the continental U.S., as well as New Caledonia, Singapore, the Solomon Islands and Puerto Rico. The worms can climb trees and are known to incessantly feed on snails and mollusks, which could greatly disturb the natural food chain.
Typically found on isolated island regions, the recent spread of the New Guinea flatworm (Platydemus manokwari) to Florida and last year to Europe is though to likely be due to the import and export of potted plants. The soil in these pots are often unchecked, and only one or two worms eggs in a shipment could be enough to threaten the mollusk population of any area.
The worms themselves are indeed flat, with a black olive color and a clear central stripe along their bodies, and measure around 40 to 65 mm in length. Their undersides are a pale white, with their mouths located in the center of their bellies. When together, the flatworms gang up to attack their prey, which includes large and small snails, earthworms, slugs and arthropods.
The worms pose a threat because their avid consumption, especially of snails, can severely upset ecosystems. Snails consume low on the food chain, but also are food for reptiles, birds and mammals that would be deprived of their food source if the flatworms were able to consume them all. If the flatworm spreads from Florida to the rest of the United States, it could potentially be a serious threat.