Wholphin
A wholphin is part false killer whale and part dolphin. Although the name suggests otherwise, a false killer whale is only a type of dolphin. There has only been one living wholphin in the world, which makes it incredibly unique.
Beefalo
Explorers inadvertently mixed cattle and bison when introducing livestock to the New World in the 18th century. From here, this breed was crossbred more purposefully, but some of these animals escaped and now wild beefalo herds can be seen along the Grand Canyon.