Letsdiskuss (image : google)

Well, right here's a few.

Xanthareel: yellow eel.
Xantis: a yak determined at some point of Himalaya area of southern Central Asia.
Xantus: a buzzing chook in Baja California.
Xantus murrelet: a small seabird inside the 'Calif. Current' system within the Pacific Ocean.
Xantusiidae: own family of night time lizards.
Xeme: an Arctic fork-tailed gull.
Xenarthra: a mammal in South America.
Xenicidae: a family of New Zealand wrens.
Xenipirostris: genus of birds from Madagascar.
Xenopeltidae: own family of reptiles including sunbeam snake- Xenopeltis.
Xenomys nelsoni: rodent in Mexico
Xenons: a narrow-billed rain woodland fowl from the Americas.
Xenopterygii: order of fishes together with clingfishes.
Xenopus: a South African clawed frog.
Xenurine: a species of armadillo; a cabassou.
Xenurus unicinctus: an armadillo local of the tropical elements of S. America.
Xerarthra: mammal related to sloth
Xerus: a kind of ground squirrel from Africa.
Xiphias Gladius: a swordfish.
Xiphosuran: a horseshoe crab.
Xoloitzcuintli: a Mexican hairless dog, a.Ok.A. Xolo.
X-Ray Tetra: a fish discovered in the Amazon and Orinoco basins.