Genus
Orcus Gailite, 1966
Luokittelu
| Organism group | Biota |
| Kingdom | Animalia |
| Phylum | Arthropoda |
| Subphylum | Crustacea |
| Superclass | Oligostraca |
| Class | Ostracoda |
| Subclass | Podocopa |
| Order | Palaeocopida |
| Suborder | Beyrichicopina |
| Palaeocopa | |
| Superfamily | Primitiopsacea |
| Family | Primitiopsididae |
| Subfamily | Venzavellinae |
| Genus | Ardennea |
| Borussulus | |
| Orcus | |
| Venzavella |