| argentina | | juncus arcticus var. mexicanus | varietas | 1 | 0 |
| canada | northwest territories | juncus arcticus | species | 3 | 0 |
| canada | nunavut | juncus arcticus | species | 7 | 0 |
| chile | | juncus arcticus var. mexicanus | varietas | 1 | 0 |
| united states | | juncus arcticus var. mexicanus | varietas | 2 | 0 |