Opinions from S. D. Webb 1969

  • 'Aelurodon meandrinus is a nomen dubium'
  • 'Astrohippus curtivallis is a subjective synonym of Calippus anatinus'
  • 'Auchenia major is recombined as Megatylopus major'
  • 'Blastomeryx scotti is recombined as Aletomeryx scotti'
  • 'Brachypsalis modicus is recombined as Brachypsaloides modicus'
  • 'Brachypsalis obliquidens is a subjective synonym of Brachypsalis pristinus'
  • 'Brachypsaloides belongs to '
  • 'Calippus martini is recombined as Astrohippus martini'
  • 'Calippus optimus is a subjective synonym of Calippus anatinus'
  • 'Cervavus sinclairi is a subjective synonym of Cranioceras unicornis'
  • 'Cosoryx burgensis is a subjective synonym of Cosoryx furcatus'
  • 'Cranioceras dakotensis is a subjective synonym of Cranioceras unicornis'
  • 'Cranioceras granti is a subjective synonym of Cranioceras unicornis'
  • 'Cranioceras mefferdi is a subjective synonym of Cranioceras unicornis'
  • 'Cynodesmus euthos is recombined as Tomarctus euthos'
  • 'Dinocyon gidleyi is recombined as Ischyrocyon gidleyi'
  • 'Dinohippus subvenus is a subjective synonym of Pliohippus supremus'
  • 'Griphippus is a subjective synonym of Pseudhipparion'
  • 'Hadrocyon is a subjective synonym of Ischyrocyon'
  • 'Hadrocyon mohavensis is recombined as Ischyrocyon mohavensis'
  • 'Hipparion affine is a subjective synonym of Neohipparion occidentale'
  • 'Hipparion dolichops is a subjective synonym of Neohipparion occidentale'
  • 'Hipparion gratum is recombined as Pseudhipparion gratum'
  • 'Hippidium interpolatum is recombined as Dinohippus interpolatus'
  • 'Hippodon is a subjective synonym of Pseudhipparion'
  • 'Hippodon speciosus is a subjective synonym of Pseudhipparion gratum'
  • 'Hippotherium retrusum is recombined as Pseudhipparion retrusum'
  • 'Hippotherium retrusum is recombined as Pseudhipparion retrusum' according to Ameghino 1904
  • 'Hippotigris clarendonensis is a subjective synonym of Pliohippus supremus'
  • 'Hippotigris parastylus is a subjective synonym of Pliohippus supremus'
  • 'Homocamelus is a subjective synonym of Procamelus'
  • 'Homocamelus caninus is a subjective synonym of Procamelus robustus'
  • 'Hypohippus matthewi is recombined as Megahippus matthewi'
  • 'Hypsoparia is a subjective synonym of Leptarctus'
  • 'Hypsoparia bozemanensis is a subjective synonym of Leptarctus primus'
  • 'Ischyrocyon hyaenodus is a subjective synonym of Ischyrocyon gidleyi'
  • 'Leptocyon belongs to Canidae'
  • 'Lutra pristina is recombined as Brachypsalis pristinus'
  • 'Martes glareae is a subjective synonym of Martes ogygia'
  • 'Martes ogygia belongs to Martes'
  • 'Martes ogygia belongs to Martes' according to Matthew 1901
  • 'Merychippus francisi is recombined as Calippus francisi'
  • 'Neohipparion niobrarense is a subjective synonym of Pseudhipparion gratum'
  • 'Plioceros is a subjective synonym of Sphenophalos'
  • 'Plioceros floblairi is recombined as Sphenophalos floblairi'
  • 'Pliocyon walkerae is a subjective synonym of Ischyrocyon gidleyi'
  • 'Pliohippus lullianus is a subjective synonym of Pliohippus supremus'
  • 'Procamelus angustidens is a subjective synonym of Protolabis heterodontus'
  • 'Procamelus dakotensis is a subjective synonym of Procamelus grandis'
  • 'Procamelus elrodi is recombined as Aepycamelus elrodi'
  • 'Procamelus fissidens is recombined as Protolabis fissidens'
  • 'Procamelus foxi is a subjective synonym of Protolabis heterodontus'
  • 'Procamelus heterodontus is recombined as Protolabis heterodontus'
  • 'Procamelus inaequidens is a nomen dubium'
  • 'Procamelus lacustris is a subjective synonym of Procamelus occidentalis'
  • 'Procamelus madisonius is a subjective synonym of Procamelus robustus'
  • 'Protohippus ansae is recombined as Astrohippus ansae'
  • 'Protohippus fossulatus is a subjective synonym of Pliohippus supremus'
  • 'Protohippus pachyops is recombined as Pliohippus pachyops'
  • 'Protohippus simus is a subjective synonym of Pliohippus pachyops'
  • 'Protohippus supremus is recombined as Pliohippus supremus'
  • 'Protolabis francisi is a nomen dubium'
  • 'Protolabis montanus is a subjective synonym of Protolabis fissidens'
  • 'Protolabis prehensilis is a nomen dubium'
  • 'Protolabis princetonianus is a subjective synonym of Protolabis fissidens'
  • 'Strobodon belongs to '
  • 'Strobodon stirtoni belongs to Strobodon'