| Onthophagus coscineus Bates, 1887 |
| Onthophagus crinitus Harold, 1869 |
| Onthophagus cuboidalis Bates, 1887 |
| Onthophagus cuevensis Howden, 1973 |
| Onthophagus curvicornis Latreille, 1811 |
| Onthophagus cyanellus Bates, 1887 |
| Onthophagus cyclographus Bates, 1887 |
| Onthophagus dicranius Bates, 1887 |
| Onthophagus dubitabilis Howden & Génier, 2004 |
| Onthophagus durangoensis Balthasar, 1939 |
| Onthophagus etlaensis Kohlmann, Escobar-Hernández & Arriaga-Jiménez, 2019 |
| Onthophagus eulophus Bates, 1887 |
| Onthophagus fuscus Boucomont, 1932 |
| Onthophagus fuscus subsp. canescens Zunino & Halffter, 1988 |
| Onthophagus fuscus subsp. fuscus Boucomont, 1932 |
| Onthophagus fuscus subsp. mycetorum Zunino & Halffter, 1988 |
| Onthophagus fuscus subsp. orientalis Zunino & Halffter, 1988 |
| Onthophagus gibsoni Howden & Génier, 2004 |
| Onthophagus gilli Delgado & Howden, 2000 |
| Onthophagus gonzaloi Moctezuma, Hernández & Sánchez-Huerta, 2022 |