Lagarosiphon major

Lagarosiphon major is a monocotic aquatic plant native to Southern Africa. Common names include African elodea, curly waterweed, oxygen weed and South African oxygen weed. It is used as freshwater aquarium plant.

It is an invasive plant in some countries. In New Zealand it is listed on the National Pest Plant Accord, and it is classed as a noxious weed in the United States. Lagarosiphon major was added to the European Union's List of Invasive Alien Species of Union concern on 3 August 2016, meaning that – amongst other things – it is illegal to sell it anywhere in the European Union or to dump it in the environment.