| Nosora azteca Casey, 1911 |
| Nudobius Thompson, 1860 |
| Nudobius arizonicus Casey, 1906 |
| Nudobius celatus Sharp, 1885 |
| Nudobius circularis Smetana, 1980 |
| Nudobius phoenicis Casey, 1906 |
| Ochthephilum Stephens, 1829 |
| Ochthephilum aberrans (Sharp, 1885) |
| Ochthephilum politum (Sharp, 1885) |
| Ochthephilum rostratum (Sharp, 1885) |
| Octavius Fauvel, 1873 |
| Octavius mexicanus Puthz, 2001 |
| Ocyota Sharp, 1883 |
| Ocyota fortepunctata Bernhauer, 1910 |
| Ocypus Leach, 1819 |
| Ocypus (Ocypus) Leach, 1819 |
| Ocypus (Ocypus) olens (Müller, 1764) |
| Oedichirus Erichson, 1839 |
| Oedichirus isthmus Herman, 2013 |
| Oedichirus sinuosus Herman, 2013 |