Irregularia
| Irregularia Temporal range:  | |
|---|---|
| Echinocardium cordatum | |
| Scientific classification | |
| Domain: | Eukaryota | 
| Kingdom: | Animalia | 
| Phylum: | Echinodermata | 
| Class: | Echinoidea | 
| Subclass: | Euechinoidea | 
| Infraclass: | Irregularia Latreille, 1825 | 
| Superorders | |
Irregularia is an extant infraclass of sea urchins that first appeared in the Lower Jurassic.