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 | Bilateria Hatschek, 1888 - bilaterians |
| subdivisio | Protostomia Grobben, 1908 - protostomes |
| phylum | Brachiopoda Duméril, 1806 - lamp shells |
| subphylum | Linguliformea |
| class | Lingulata |
| order | Acrotretida Kühn, 1949 † |
| superfamily | Acrotretoidea Schuchert, 1893 † |
| family | Ceratretidae Rowell, 1965 † |