Meteor goldfish

The Meteor goldfish is a tailless breed of fancy goldfish thought to have been developed by goldfish breeders during the late 19th or early 20th century. The meteor goldfish lacked a tail fin, but had a well-developed anal fin in the tail fin's position. The other fins of the meteor goldfish were elongated, and it was a competent swimmer despite its lack of a tail.
Because no photographs of the breed appear to exist, the Bristol Aquarists' Society has suggested that the meteor goldfish may simply be a rumor. It has been speculated to be related to the Egg-fish.
External links.
Purported photo of a meteor goldfish