Elodea nuttallii is a species of waterweed known by the common name western waterweed or Nuttall's waterweed. This is a perennial aquatic plant which is native to North America where it grows submersed in lakes, rivers, and other shallow water bodies. It is also found in Eurasia, where it is commonly weedy; it is not known as a weed species in its native range. It is sometimes used as an aquarium plant. The first european evidence of Elodea nuttallii was probably 1914 in England, though it had been determined wrongly as Hydrilla verticillata. It is a invasive species to Europe and is now covering practically the whole continent.