Position in a system
| system | Vitae - living organisms |
| domain | Eukaryota Whittaker & Margulis, 1978 - lifeforms with nucletic cells |
| superregnum | Unikonta |
| system | Opisthokonta Cavalier-Smith, 1987 |
| kingdom | Animalia Linnaeus, 1758 - animals |
| subregnum | Eumetazoa Butschli, 1910 |
| divisio | Radiata Linnaeus, 1758 |
| phylum | Cnidaria Hatschek, 1888 - anemones, corals and jellyfish |
| class | Hydrozoa Owen, 1843 - hydra and freshwater jellyfish |
| order | Hydroida Johnston, 1836 |
| suborder | Leptomedusae Haeckel, 1866 |
| superfamily | Eirenoidea Haeckel, 1879 |
| family | Eirenidae Haeckel, 1879 |
| genus | Phialopsis Torrey, 1909 |
| species | Phialopsis diegensis Torrey, 1909 |