| Name | Euphorbia xantii Engelmann |
| Authorship | Engelmann |
| Rank | Species |
| NomenclaturalStatus | Unknown |
| Placed in | Euphorbia Linnaeus |
| Holdings | 1 Specimen held in the Harvard University Herbaria identified as Euphorbia xantii Engelmann |
| Identification made in | 1996 (1) |