Order
Helodontiformes Patterson, 1965
Classification
| Organism group | Biota | 
| Kingdom | Animalia | 
| Phylum | Chordata | 
| Subphylum | Vertebrata | 
| Infraphylum | Gnathostomata | 
| Class | Chondrichthyes | 
| Order | Holocephali | 
| Superorder | Holocephalomorpha | 
| Order | Helodontiformes | 
| Family | Helodontidae | 
| Order | Petalodontiformes |