n = 8
| Scientific Name | Author | Valid Name | Family | English Name |
|---|---|---|---|---|
| Ichthyomyzon bdellium | (Jordan, 1885) | Ichthyomyzon bdellium | Petromyzontidae | Ohio lamprey |
| Ichthyomyzon castaneus | Girard, 1858 | Ichthyomyzon castaneus | Petromyzontidae | Chestnut lamprey |
| Ichthyomyzon fossor | Reighard & Cummins, 1916 | Ichthyomyzon fossor | Petromyzontidae | Northern brook lamprey |
| Ichthyomyzon gagei | Hubbs & Trautman, 1937 | Ichthyomyzon gagei | Petromyzontidae | Southern brook lamprey |
| Ichthyomyzon greeleyi | Hubbs & Trautman, 1937 | Ichthyomyzon greeleyi | Petromyzontidae | Mountain brook lamprey |
| Ichthyomyzon hirudo | Girard, 1858 | Ichthyomyzon castaneus | Petromyzontidae | Chestnut lamprey |
| Ichthyomyzon hubbsi | Raney, 1952 | Ichthyomyzon greeleyi | Petromyzontidae | Mountain brook lamprey |
| Ichthyomyzon unicuspis | Hubbs & Trautman, 1937 | Ichthyomyzon unicuspis | Petromyzontidae | Silver lamprey |