Opinions from E. Weston and J.-R. Boisserie 2010
- 'Archaeopotamus belongs to Hippopotaminae'
- 'Cetancodonta belongs to Cetartiodactyla'
- 'Cetartiodactyla belongs to Mammalia'
- 'Choeropsis belongs to Hippopotaminae'
- 'Hexaprotodon belongs to Hippopotaminae'
- 'Hexaprotodon bruneti belongs to Hexaprotodon'
- 'Hexaprotodon dulu is recombined as Hippopotamus dulu'
- 'Hexaprotodon garyam belongs to Hexaprotodon'
- 'Hexaprotodon harvardi is recombined as Archaeopotamus harvardi'
- 'Hexaprotodon karumensis is recombined as Hippopotamus karumensis'
- 'Hexaprotodon karumensis is recombined as Hippopotamus karumensis' according to Coryndon 1977
- 'Hexaprotodon lothagamensis is recombined as Archaeopotamus lothagamensis'
- 'Hexaprotodon sahabiensis belongs to Hexaprotodon' according to Gaziry 1987
- 'Hexaprotodon sahabiensis belongs to Hexaprotodon'
- 'Hippopotamidae belongs to Hippopotamoidea'
- 'Hippopotaminae belongs to Hippopotamidae'
- 'Hippopotamoidea belongs to Cetancodonta'
- 'Hippopotamus belongs to Hippopotaminae'
- 'Hippopotamus aethiopicus belongs to Hippopotamus'
- 'Hippopotamus amphibius belongs to Hippopotamus'
- 'Hippopotamus coryndonae belongs to Hippopotamus' according to Geze 1985
- 'Hippopotamus coryndonae belongs to Hippopotamus'
- 'Hippopotamus gorgops belongs to Hippopotamus'
- 'Hippopotamus hipponensis is recombined as Hexaprotodon hipponensis'
- 'Hippopotamus imagunculus is recombined as Hexaprotodon imaguncula'
- 'Hippopotamus laloumena belongs to Hippopotamus' according to Faure and Guerin 1990
- 'Hippopotamus laloumena belongs to Hippopotamus'
- 'Hippopotamus lemerlei belongs to Hippopotamus'
- 'Hippopotamus liberiensis is recombined as Choeropsis liberiensis'
- 'Hippopotamus madagascariensis belongs to Hippopotamus' according to Guldberg 1883
- 'Hippopotamus madagascariensis belongs to Hippopotamus'
- 'Hippopotamus protamphibius belongs to Hippopotamus'
- 'Kenyapotaminae belongs to Hippopotamidae'
- 'Kenyapotamus belongs to Kenyapotaminae'
- 'Kenyapotamus coryndoni is corrected as Kenyapotamus coryndonae and belongs to Kenyapotamus'
- 'Kenyapotamus ternani belongs to Kenyapotamus'
- 'Saotherium belongs to Hippopotaminae'
- 'Saotherium mingoz belongs to Saotherium'
- 'Trilobophorus is a subjective synonym of Hippopotamus'
- 'Trilobophorus afarensis is recombined as Hippopotamus afarensis'