Salvinia molesta

Salvinia molesta, commonly known as giant salvinia, is also widely called Kariba weed after it infested a large portion of Lake Kariba between Zimbabwe and Zambia. It is a free-floating aquatic fern, with fronds that are 0.5–4 centimetres (0.20–1.6 in) long and broad, with a bristly, waterproof surface caused by the hair-like strands that join at the end to form eggbeater shapes. The fronds are produced in pairs with a third modified root-like frond that hangs in the water. It originates in south-eastern Brazil. S. molesta has been accidentally introduced or escaped to countless lakes throughout the world. Since 2019, S. molesta has been included in the European Union's List of invasive alien species of Union concern. The species cannot be imported, cultivated, transported, commercialized, planted, nor intentionally released into the environment in the European Union. In the United States, it is in Caddo Lake in Texas, where it has caused eutrophication....read more on Wikipedia.