the root (no rank)
Eukaryota (domain)
Metazoa (kingdom)
Echinodermata (phylum)
Echinozoa (superclass)
Echinoidea (class)
sea urchin (common name)
sea urchins (common name)
[hide inferior taxa]
Euechinoidea (subclass)
Perischoechinoidea (subclass)