| Microtus oaxacensis Goodwin, 1966 |
| Microtus pennsylvanicus (Ord, 1815) |
| Microtus pennsylvanicus subsp. chihuahuensis Bradley & Cockrum, 1968 |
| Microtus phaeus Merriam, 1892 |
| Microtus quasiater (Coues, 1874) |
| Microtus umbrosus Merriam, 1898 |
| Nelsonia Merriam, 1897 |
| Nelsonia goldmani Merriam, 1903 |
| Nelsonia goldmani subsp. cliftoni Genoways & Jones, 1968 |
| Nelsonia goldmani subsp. goldmani Merriam, 1903 |
| Nelsonia neotomodon Merriam, 1897 |
| Nelsonia neotomodon subsp. cliftoni Genoways & Jones, 1968 |
| Nelsonia neotomodon subsp. goldmani Merriam, 1903 |
| Nelsonia neotomodon subsp. neotomodon Merriam, 1897 |
| Neotoma Say & Ord, 1825 |
| Neotoma abbreviata Goldman, 1909 |
| Neotoma albigula Hartley, 1894 |
| Neotoma albigula subsp. albigula Hartley, 1894 |
| Neotoma albigula subsp. durangae J. A. Allen, 1903 |
| Neotoma albigula subsp. leucodon Merriam, 1894 |