Opinions from E. Delson 1971
- 'Ectocion ralstonensis is a subjective synonym of Ectocion osbornianus'
- 'Esthonyx spatularius is a subjective synonym of Esthonyx bisulcatus'
- 'Esthonyx spatularius belongs to Esthonyx' according to Cope 1880
- 'Leipsanolestes is a subjective synonym of Entomolestes'
- 'Leipsanolestes siegfriedti is recombined as Entomolestes siegfriedti'
- 'Leptacodon is a subjective synonym of Entomolestes'
- 'Palaeosinopa veterrima is a subjective synonym of Palaeosinopa didelphoides'
- 'Palaeosinopa veterrima belongs to Palaeosinopa' according to Matthew 1901
- 'Pantolestes metsiacus is recombined as Diacodexis metsiacus'
- 'Pantolestes metsiacus is recombined as Diacodexis metsiacus' according to Guthrie 1967
- 'Parapheliscus is a subjective synonym of Apheliscus'
- 'Parapheliscus bjorni is a subjective synonym of Phenacolemur praecox'
- 'Parapheliscus bjorni belongs to Parapheliscus' according to Van Valen 1967
- 'Parapheliscus wapitiensis is a subjective synonym of Apheliscus nitidus'
- 'Parapheliscus wapitiensis belongs to Parapheliscus' according to Van Valen 1967
- 'Paratetonius is a subjective synonym of Tetonius'
- 'Paratetonius steini is a subjective synonym of Tetonius homunculus'
- 'Paratetonius sublettensis is a subjective synonym of Tetonius homunculus'
- 'Phenacodus copei is a subjective synonym of Phenacodus vortmani'
- 'Phenacodus copei is a subjective synonym of Phenacodus vortmani' according to Guthrie 1967
- 'Phenacodus gidleyi is a subjective synonym of Phenacodus matthewi'
- 'Phenacodus gidleyi is a subjective synonym of Phenacodus vortmani' according to Bown 1979
- 'Phenacolemur citatus is a subjective synonym of Phenacolemur praecox'
- 'Phenacolemur citatus is a subjective synonym of Phenacolemur praecox' according to Simpson 1955
- 'Phenacolemur jepseni is a subjective synonym of Phenacolemur praecox'
- 'Phenacolemur jepseni belongs to Phenacolemur' according to Simpson 1955
- 'Prolimnocyon robustus is a subjective synonym of Paeneprolimnocyon mordax'
- 'Scenopagus is a subjective synonym of Talpavus'
- 'Sinopa mordax is recombined as Paeneprolimnocyon mordax'
- 'Sinopa shoshoniensis is recombined as Arfia shoshoniensis'
- 'Tetonius musculus belongs to Tetonius'
- 'Tetonius tenuiculus is a subjective synonym of Tetonius musculus'
- 'Tetonoides is a subjective synonym of Tetonius'
- 'Tetonoides pearcei is a subjective synonym of Tetonius musculus'