| Xanthium strumarium L. | map | images (1) (2) |
| Xanthorhiza simplicissima Marsh. | map | images (1) |
| Xerophyllum asphodeloides (L.) Nutt. | map | |
| Xyris ambigua Bey. ex Kunth | map | |
| Xyris baldwiniana J.A. Schultes | map | |
| Xyris brevifolia Michx. | map | |
| Xyris caroliniana Walt. | map | |
| Xyris chapmanii Bridges & Orzell | map | |
| Xyris difformis Chapman var. curtissii (Malme) Kral | map | |
| Xyris difformis Chapman var. difformis | map | |
| Xyris difformis Chapman var. floridana Kral | map | |
| Xyris elliottii Chapman | map | |
| Xyris fimbriata Ell. | map | |
| Xyris flabelliformis Chapman | map | |
| Xyris iridifolia Chapman | map | |
| Xyris jupicai L.C. Rich. | map | |
| Xyris platylepis Chapman | map | |
| Xyris scabrifolia Harper | map | |
| Xyris serotina Chapman | map | |
| Xyris smalliana Nash | map | |
| Xyris stricta Chapman | map | |
| Xyris torta Sm. | map | |