| Family | Scientific Name | Common Name | Habitat | Distribution | Image |
|---|---|---|---|---|---|
| Lythraceae | Trapa bispinosa var. jinumae | Two-spined Water-chestnut, Japanese Water-Chestnut | Estuarine and pond waters. | Native of e. Asia. |  |
| Lythraceae | Trapa natans | European Water-chestnut, Water-caltrop, Four-spined Water-chestnut | Farm ponds and other stagnant or slow-moving water. | Native of Eurasia and Africa. |  |