WAlphadontidae
WAmebelodontidae
WAmphilemuridae
WAnancidae
WBarytheriidae
WCainotheriidae
WChoerolophodontidae
WChoeropotamidae
WDesmostylidae
WDidolodontidae
WDiprotodontidae
WHapalodectidae
WHaramiyidae
WHelohyidae
WMacraucheniidae
WMegalocnidae
WMegatheriidae
WMoeritherium
WNothrotheriidae
WNotostylopidae
WNyctitheriidae
WDesmostylia
WPalorchestidae
WPhenacodontidae
WProterotheriidae
WPtolemaiida
WThylacosmilidae
WTriconodontidae
WTriisodontidae
WUintatheriidae
WVolaticotherini
WWaipatia
WXiphodontidae