Which mammal is the only extant species in the genus Acinonyx? The answer is the cheetah.
The cheetah, Acinonyx jubatus, is the only living species in the genus Acinonyx. It is a large feline specialised for pursuit hunting, with long legs, a flexible spine, powerful hind limbs and a lightweight body. These adaptations help it reach exceptional speeds over short distances.
Its scientific history is more complicated than the quiz answer suggests. Johann Christian Daniel von Schreber described the animal in 1775 under the name Felis jubatus, while the genus name Acinonyx was proposed by Joshua Brookes in 1828. Fossil cheetah-like cats once lived in Eurasia and North America, but they are extinct and do not change the fact that only one Acinonyx species survives today.
Cheetahs are often confused with leopards and jaguars. Their solid black spots, slim build and black tear-like facial markings distinguish them from the rosettes and heavier proportions of those Panthera cats. Unlike most felids, cheetahs have non-retractable claws that improve traction while running.