| 释义 |
{{A-Z multipage list|List of fictional alien species}}| Name | Source | Type | | X-ists | Church of the SubGenius | | X-Nauts | The Thousand-Year Door | | X Parasites | Metroid Fusion | | Xandarians | Marvel Comics | Humanoid | | Xanthuans | DC Comics' Legion of Super-Heroes | | Xarians | Battlelords of the 23rd Century | | Xarquids | Terror from the Deep | | Xchagger | Star Control | | Xel'Naga | StarCraft | | Xenexian | Star Trek | | Xenomorphs | Alien movies | Parasitic | | Xenu | Scientology | | Xiangs | 2300 AD | | Xilians | Invasion of Astro-Monster and Final Wars | Humanoid | | Xindi | Star Trek | Humanoid | | Xorda | Sonic the Hedgehog comics | | Xxcha | Twilight Imperium | Peaceful arboreal testudinoids | | Xyrillian | Star Trek |
1 : Lists of fictional alien species |