Although the mammals are well studied in comparison to other animal groups, a number of new species are still being discovered. This list includes extantmammalspecies discovered, formally named, or brought to public light in the year 2000 or later. Notable subspecies are also included, as are mammals rediscovered after being declared, or seriously suspected to be, extinct. Newly discovered fossils are not included.
Marsupials
At least five new species of marsupials have been discovered since 2000:
In 2001, genetic evidence emerged that the African elephant, once thought to be a single species, was in fact two, as the smaller African forest elephant was in fact a distinct species. L. africana is now commonly referred to as the African bush elephant. Strictly speaking, this is not a newly discovered species, but simply an alternative taxonomic treatment, as cyclotis already was widely recognized, but only as a subspecies.
Since 2000, at least 25 new species of primate have been described—16 lemurs and nine monkeys, including the golden palace monkey or Madidi titi, named by auction.
A number of rodents are described each year. Notable among those described since 2000 are the Cypriot mouse, Mus cypriacus, and the Laotian rock rat, Laonastes aenigmamus, which represents a family thought to be extinct since the Miocene, and has been described as a living fossil.
Bats
At least 30 new species of bat have been described since 2000. The new species were found in Africa, Latin America, Asia, Oceania, and Europe.
Since 2000, several new species of cetartiodactyl have been described, including three aquatic species and three terrestrial ungulates. Additionally, the northern right whale, previously considered a single species, was proposed to consist of a Pacific and an Atlantic species.
Carnivorans
Several new subspecies of previously known species were described. Additionally, an alternative taxonomic treatment of the clouded leopard was proposed, in which the taxondiardi, previously considered a subspecies of Neofelis nebulosa, was proposed a separate species, the Sunda clouded leopard. In 2013, the olinguito, living in the Andean cloud forest, was determined to be a distinct species. It had previously been categorized as a small olingo.