The taxonomy among "Mazama" species has changed significantly in the last decades, and as recently as 1999, some authorities only recognized four species. These four "species", "M. americana", "M. gouazoubira", "M. rufina", and "M. chunnyi", included several distinct populations that subsequently were elevated to species status, resulting in a total of nine different species being recognized in "Mammal Species of the World" in 2005. A tenth species, "M. nemorivaga", has traditionally been included in "M. gouazoubira", but this was shown to be mistaken in 2000. "M. nemorivaga" was not recognized as a separate species in "Mammal Species of the World", but this was apparently in error. Yet another species, the fair brocket ("M. tienhoveni"), has recently been described from the lower Amazon basin. What may be an undescribed small species of brocket with a reddish coat and blackish legs has been photographed in the lowlands of Manú National Park in Peru, and based on sight records may also occur in northwestern Bolivia.