The Redtail Blue Variatus is a North American livebearer related to and in the same genus, Xiphophorus, as the swordtails. Most commercial strains of platies have mixed heritage, including ancestors from X. helleri, X. maculatus and X. variatus. This fish is largely descended from X. variatus. Males often reach 4cm (1.5 in.). Females are somewhat larger and much heavier. Males have light blue bodies, yellow dorsals and red tails. Females have gray-blue bodies and red caudals. This fish has no natural range, but of its ancestors hail from Mexican and Central America.