Xiphophorus hellerii swordtail fish, (Heckel, 1848), a tropical fish belonging to the genus Xiphophorus poeciliidae. River basins in Mexico, Guatemala and other places. A gentle, lively, and small fish polyculture. There was a male caudal lobe extending process of sword shaped. Closely related to Platy, widely used in genetics and medical research. For the side of the body with the green swordtail fish, a red stripe, but has developed many varieties. After Chinese swordtail breeding experts raised for years, we have bred high sail, sail and sail short lines, one of the most ornamental value for chrysanthemum sail, called the best.