Elodea crispa 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.

[1] In New Zealand it is listed on the National Pest Plant Accord and is classed as a noxious weed in the United States.

[3] This means – amongst other things – that it is illegal to sell this plant in the whole of the European Union or to dump it in the environment.

[4] Ireland: Co.Galway in parts of upper Lough Corrib.