The Manx is the cat breed known for its lack of a tail. Originating on the Isle of Man, the Manx is famous for its rounded body, powerful hind legs, and tail that may be completely absent or reduced to a short stump.
The breed’s taillessness results from a naturally occurring mutation affecting tail development. Not every Manx cat is entirely tailless: breeders and registries use terms such as “rumpy” for cats with no visible tail, “riser” for a small cartilage bump, and “stumpy” or “stubby” for short tails. Fully tailed cats can also occur in Manx litters.
The Manx is sometimes confused with other naturally short-tailed breeds, including the Japanese Bobtail and American Bobtail. Those breeds have different histories and genetic traits. The Manx developed on the isolated Isle of Man, where limited genetic diversity helped the mutation become common.
The tailless gene also has important breeding implications. Inheriting two copies can cause serious developmental problems, so responsible breeders do not simply mate two completely tailless Manx cats. Long-haired Manx cats are often called Cymrics, although registry terminology varies.