Gifford et al. (2018) proposed a nomenclature system for endogenous retroviruses (ERV)
For the sake of simplicity, the shared viral hierarchy for all elements is listed separately:
| Root | Realm | Kingdom | Phylum | Class | Order |
|---|---|---|---|---|---|
| Virus | Riboviria | Pararnavirae | Artverviricota | Revtraviricetes | Ortervirales |
| Family | Subfamily | Clade | Genus | Repbase Superfamily | ERV |
|---|---|---|---|---|---|
| Retroviridae | Spumavirinae | Spumavirus | |||
| Retroviridae | Orthoretrovirinae | III | Spumavirus-related | ERV3 | ERV/Endogenous Retrovirus-L |
| Retroviridae | Orthoretrovirinae | I | Epsilonretrovirus | ERV1 | |
| Retroviridae | Orthoretrovirinae | I | Gammaretrovirus | ERV1 | |
| Retroviridae | Orthoretrovirinae | I | Gammaretrovirus/Epsilonretrovirus-related | ERV1 | ERV/Endogenous Retrovirus-H |
| Retroviridae | Orthoretrovirinae | I | Gammaretrovirus/Epsilonretrovirus-related | ERV1 | ERV/Endogenous Retrovirus-W |
| Retroviridae | Spumavirinae | II | Deltaretrovirus | ||
| Retroviridae | Spumavirinae | II | Lentiretrovirus | ||
| Retroviridae | Spumavirinae | II | Alpharetrovirus | ERV2 | |
| Retroviridae | Spumavirinae | II | Betaretrovirus | ERV2 | |
| Retroviridae | Orthoretrovirinae | II | Alpharetrovirus/Betaretrovirus-related | ERV2 | ERV/Endogenous Retrovirus-K |
| Retroviridae | Orthoretrovirinae | II | Alpharetrovirus/Betaretrovirus-related | ERV2 | IAP |