- The speciose genus Palaeotherium plus " Anoplotherium " and the families Xiphodontidae and Amphimerycidae were observed to disappear completely.
- "' Xiphodontidae "'is an extinct terrestrial herbivores . " Paraxiphodon " suggests that they survived into the Lower Oligocene, at least.
- It's difficult to see xiphodontidae in a sentence. 用xiphodontidae造句挺難的