| Chattian first appearance(expression, geohistory, appearance, period) |
| Extant Oligocene first appearance(expression, geohistory, appearance, period) |
| Rupelian first appearance(expression, geohistory, appearance, period) |
| Aceratheriinae(noun, animal, geohistory, appearance) |
| Afossochiton(noun, animal, geohistory, appearance) |
| Ailuridae(noun, animal, geohistory, appearance) |
| Amphechinus(noun, animal, geohistory, appearance) |
| Andrias scheuchzeri(expression, animal, geohistory, appearance) |
| Borophaginae(noun, animal, geohistory, appearance) |
| Chubutherium(noun, animal, geohistory, appearance) |
| Dromornithidae(noun, animal, geohistory, appearance) |
| Ekgmowechashala(noun, animal, geohistory, appearance) |
| Hanleya(noun, animal, geohistory, appearance) |
| Kentriodontidae(noun, animal, geohistory, appearance) |
| Mammacyon(noun, animal, geohistory, appearance) |
| Merycochoerus(noun, animal, geohistory, appearance) |
| Miotylopus(noun, animal, geohistory, appearance) |
| Neocynodesmus(noun, animal, geohistory, appearance) |
| Octodontotherium(noun, animal, geohistory, appearance) |
| Orophodontidae(noun, animal, geohistory, appearance) |