| Iphthimus lewisii Horn, 1870 |
| Iphthimus zopheroides Horn, 1874 |
| Isaminas Champion, 1887 |
| Isaminas breedlovei Doyen, 1988 |
| Isaminas brevicollis Champion, 1887 |
| Isaminas reticuloides Doyen, 1988 |
| Isicerdes Champion, 1885 |
| Isicerdes occultus Champion, 1885 |
| Isicerdes vicinus Champion, 1892 |
| Isomira Mulsant, 1856 |
| Isomira acuta Campbell, 1968 |
| Isomira brevicollis Champion, 1888 |
| Isomira championi Campbell, 1968 |
| Isomira howdeni Campbell, 1968 |
| Isomira howdeni subsp. hidalgoensis Campbell, 1968 |
| Isomira howdeni subsp. howdeni Campbell, 1968 |
| Isomira mexicana Campbell, 1968 |
| Isomira obsoleta Champion, 1888 |
| Isomira rotundata Campbell, 1968 |
| Isomira subaenea Champion, 1888 |