Superclass
Euchelicerata Weygoldt et Paulus, 1979
Classification
| Organism group | Biota | 
| Kingdom | Animalia | 
| Phylum | Arthropoda | 
| Subphylum | Chelicerata | 
| Superclass | Euchelicerata | 
| unranked | Prosomapoda | 
| Class | Arachnida | 
| Merostomata | |
| Pycnogonida | |
| Xiphosura | |
| Order | Eurypterida |