Dodatak:Popis sisavaca, Or
Orc uredi
, Orcaella
Orcinus Fitzinger, 1860 uredi
- Orcinus citoniensies (Capellini, 1883) †
- Orcinus meyeri Brandt 1873 †
- Orcinus orca (Linnaeus, 1758)
- Orcinus orca eschrichti Reinhardt 1866
- Orcinus orca pacifica Gray 1870
- Orcinus paleorca Matsumoto, 1937 †
Mammalia → Cetacea → Odontoceti → Delphinida → Delphinoidea → Delphinidae
Ord uredi
†Ordolagus de Muizon 1977 uredi
- †Ordolagus teilhardi Burke 1941
Mammalia → Lagomorpha → Leporidae
Ore uredi
, Oreamnos , Oreotragus
Orn uredi
, Ornithorhynchidae , Ornithorhynchus
Ort uredi
, Orthogeomys
Ory uredi
, Orycteropodidae , Orycteropus
Oryctolagus Lilljeborg 1874 uredi
- Oryctolagus cuniculus (Linnaeus, 1758)
- Oryctolagus cuniculus algirus (Loche, 1858)
- Oryctolagus cuniculus brachyotus Trouessart, 1917
- Oryctolagus cuniculus cnossius Bate, 1906
- Oryctolagus cuniculus cuniculus (Linnaeus, 1758)
- Oryctolagus cuniculus habetensis Cabrera, 1923
- Oryctolagus cuniculus huxleyi Haeckel, 1874
Mammalia → Lagomorpha → Leporidae → Leporinae , Oryx , Oryzomys , Oryzorictes