How are horses classified within the genus Equus?

Within the genus Equus, the horse is classified as a single species known as Equus caballus. This genus encompasses all modern equines, including not only domestic horses but also asses (E. asinus) and zebras.123

While all domestic horses belong to the species E. caballus, they are categorized into numerous varieties referred to as breeds. Additionally, certain wild equines are classified as subspecies within this framework, such as Przewalski’s horse, which is sometimes designated as E. caballus przewalskii or E. ferus przewalskii. The genus Equus itself is part of the family Equidae, which includes all modern horses, zebras, and asses.123