African elodea (Curly waterweed) – Lagarosiphon major

African elodea is native to southern Africa. As an established alien species, it is present in Europe in the UK, the Netherlands, Belgium, Germany, France, Switzerland, Austria and Italy, and in other parts of the world, at least on the island of Reunion and New Zealand. The species has been eradicated from Australia but a new invasion is already in progress. It prefers the cool waters of the temperate zone (optimum water temperature 20–23°C, maximum approximately 25°C).