Giant Flatworms Invade France

By Lauren Sigfusson | May 22, 2018 11:13 am

This giant invasive flatworm, a Diversibipalium ‘blue,’ made its way to a French territory off Africa. (Credit: Laurent Charles – CCBY 4.0)

Worms have a way of appearing in strange, unwanted places: Inside feet, eyeballs and stomachs. Turns out some are even invading countries.

Giant predatory flatworms have inched their way into France and its overseas territories on four continents, according to a study released Tuesday in PeerJ. The invasive flatworms were documented by citizen scientists and managed to stay under the radar for more than two decades. This is the first study to cover the invasion.

Wormy Worm

The study is based on contributions from more than 100 citizen scientists, dating as far back as 1999. Three species were found in France Bipalium kewense, Diversibipalium multilineatum, and an unnamed Diversibipalium ‘black’ species. B. kewense was also spotted in French territories in Oceania, South America, Central America, and southeast Africa. B. vagum was seen in South America, Central America and the United States (Florida). There was even a possible new species, a new blue variant of Diversibipalium found on an island off southeast Africa.

These flatworms are part of a group known as bipaliines and are sometimes called hammerhead flatworms, for obvious reasons. They can also reach up to 1 meter, or more than 3 feet, in length (*shudder*). While other invasive flatworms have been documented in these regions, they are rather small, only about two inches in length at a maximum. Hammerhead flatworms are originally from Southeast Asia, but are now dispersed across the world thanks largely to the global trade in plants.

Hammerhead flatworms feed on animals living in the soil — earthworms are a common target for some species. The creatures are likely able to track their prey through the soil, and use sticky secretions to grab hold of them. Digestion begins even before ingestion in some cases — the worms eject part of their throat to begin breaking prey down before sucking the softened tissues back inside.

Scientists warn that these soil dwellers could affect the biodiversity of native animals and soil ecology, though studies of their ecological impact have yet to be completed.

“As scientists, we were amazed that these long and brightly colored worms could escape the attention of scientists and authorities in a European developed country for such a long time; improved awareness about land planarians is certainly necessary,” the authors wrote in the study. Stay alert, folks.

CATEGORIZED UNDER: Living World, top posts
MORE ABOUT: animals
  • El Howard

    The French didn’t worry much about this until they found out they’re not really that tasty when cooked in a garlic butter sauce.

    • The Demon Slick

      What’s really funny is how they have no trouble recognizing the invasive foreign species can be harmful to their own ecosystem, but they can’t figure out that humans from another culture might cause problems.

      • roadwalker

        And what culture would that be? France began with Gallic culture, followed by the Romans, the Visigoths, the Moors, the Germans, the English and even some contributions from the Americans. There is no such thing as ‘pure French culture.’

        • The Demon Slick

          Do the French endorse pedophilia? Female genital mutilation? Polygamy? The subjugation of women? Well their newest imported culture just loves that stuff.

        • Demonhunter13

          Their culture need not be “pure” or unchanged over centuries in order to be degraded by the influence of evil aspects of some other culture. Your point has no validity.

    • Jerome Barry


    • Wade Carmen

      STill better than Denny’s.

  • TLongmire

    That is a beautiful worm and if I were into fungi I’d be studying which ones that species has allied with.

  • Genesis 11:9

    Once arrived, the worms are part of the biodiversity of any area in which they may be found. To get one’s panties in a twist because “these soil dwellers could affect the biodiversity of native animals and soil ecology” seems to lack intellectual coherence.

    • Eric Bjerregaard

      Sometimes a new part of the biodiversity is best eliminated. For the sake of the rest. There is nothing sacred about an invasive species.

      • Genesis 11:9

        And I suppose it’s you who gets to decide whether a species is “invasive” or not? Like I said, a complete lack of both intellectual honesty and coherence. Just because you can rationalize away a glaring logical inconsistency doesn’t make it any less idiotic.

        • Eric Bjerregaard

          And he returns for another poorly thought out comment. I never said I get to decide. Neither I nor the author said anything that lacks coherence or intellectual honesty. There is no inconsistency. The jury is still out on whether or not these are harmful. And I strongly support removal of damaging exotics. such as the pythons in Florida.

          • Genesis 11:9

            And he returns for another poorly thought out comment. Indeed.

          • Eric Bjerregaard

            Aaah, so you got nothing. Thought so.

          • workingmansdem

            I’m new here. Who’s the clown genesis? I take it he is always like this?

          • Eric Bjerregaard

            I have no clue who he is. One of the science based news letters I get posted this story. That is how I got here.

          • Genesis 11:9

            Why not take a shot, son. You really have nothing to lose. What’s your beef with someone whose mind ranges farther than yours can imagine?

          • workingmansdem

            Than I care to imagine, thank you very much. And by the way, the correct usage is “further”. Farther is for physical distances. A common error among the poorly educated.

          • ɹǝdɯoʇs ɥʇʎɯ

            Europeans were some of the early “damaging exotics”. I don’t think there’s any chance of eradicating them.

          • Eric Bjerregaard

            Wow, another master of the obvious.

      • Jerome Barry

        We could gift you some of our feral hogs. That would make short work of the giant hammerhead hog nuggets.

        • Eric Bjerregaard

          Ummm, no thanks, we already have those. I have seen some in the river flood plain west of me. My land is higher sandhills. they seem to prefer wetter areas to cause trouble and destruction. You are welcome to our armadillos though.

    • Jerome Barry

      For instance, the humble earthworm was not present in North America before Europeans arrived. Nobody’s complaining about earthworms now.

  • John C


    • Trumpforprison2018

      Trump the sexual predator for PRISON 2018

    • Trumpforprison2018


    • John Wilson

      You need a hobby TFP2018…or something to play with.

  • Jerome Barry

    Hush! They (D’s) will get the notion to register them to vote.

    • mlentz

      Even if they aren’t dead yet?

  • max fish

    I wonder how long until the French put up the white flag and capitulate under the force of the invasion. Probably like two weeks.

  • Wade Carmen

    Looks like a worm with the head of a hammerhead shark.


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