WAcritohippus
WAncylotherium
WAnisodon
WArchaeohippus
WChalicotherium
WDesmatippus
WDinohippus
WHippotherium
WHypohippus
WHyracodontidae
WKalimantsia
WMegahippus
WMerychippus
WMoropus
WNannippus
WNexuotapirus
WParahippus
WParatapirus
WPlesiotapirus
WProtapirus
WPseudhipparion
WScaphohippus