| Name | Children | Media (from resource) | Traits |
|---|---|---|---|
| Xiphias gladius Linnaeus 1758 (Broadbill Swordfish) | 0 | 2 | 0 |
| Xiphiidae (swordfishes) | 0 | 0 | 0 |
| Xiphophorus (Platyfish) | 0 | 2 | 0 |
| Xiphosura | 0 | 2 | 0 |
| Xylaria | 2 | 2 | 0 |
| Xylaria hypoxylon (L.) Grev. 1824 (Candle-snuff Fungus) | 0 | 2 | 0 |
| Xylaria polymorpha (Pers.) Grev. 1824 (dead man's fingers) | 0 | 2 | 0 |
| Xylariaceae | 2 | 1 | 0 |
| Xylariales | 1 | 0 | 0 |
| Ornithodira | 1 | 0 | 0 |
| Xylena (Swordgrass Moths) | 1 | 0 | 0 |
| Xylena exsoleta Linnaeus 1758 (Sword-grass moth) | 0 | 2 | 0 |
| Xyleninae | 0 | 0 | 0 |
| Xylia | 1 | 0 | 0 |
| Xylia xylocarpa (Roxb.) Taub. | 0 | 2 | 0 |
