Family
Cyathaxoniidae Milne-Edwards et Haime, 1851
List of species
1. Sutherlandinia gothlandica Weyer, 1978 | Wenlock
Classification
| Organism group | Biota | 
| Kingdom | Animalia | 
| Phylum | Cnidaria | 
| Subphylum | Anthozoa | 
| Subclass | Rugosa | 
| Order | Stauriida | 
| Suborder | Streptelasmatina | 
| Family | Acrophyllidae | 
| Cyathaxoniidae | |
| Subfamily | Sutherlandiniinae | 
| Family | Kodonophyllidae | 
| Mucophyllidae | |
| Paliphyllidae | |
| Polycoeliidae | |
| Primitophyllidae | |
| Streptelasmatidae |