These were known in Japan as  or , or translated in English "long tail carp". Randy LeFever, the son of Wyatt LeFever, a noted breeder of koi, is credited with suggesting they looked like butterflies, for which the breed is named.
The long tail carp, known in Japan as  or , or translated into English as "long tail carp", was named after their resemblance to butterflies, suggested by Randy LeFever, son of a renowned koi breeder, Wyatt LeFever.