Invasive flatworms up to 40 centimeters long have been found in France, but it seems they’ve been around for some time, The Washington Post reports. Scientists, shocked by recent photographs of hammerhead flatworms crawling around French gardens, put out a public call for additional sightings. They received more than 100 reports, including a worm caught on a home video from 1999. A lack of education about the flatworms, native to Asia, may have helped the creatures go undetected for so long, the authors write in PeerJ. But they warn that the invasive predators, which feed on earthworms, could pose a danger to native wildlife.