Atelostomata
| Atelostomata Temporal range:  | |
|---|---|
| Echinocardium cordatum | |
| Scientific classification | |
| Domain: | Eukaryota | 
| Kingdom: | Animalia | 
| Phylum: | Echinodermata | 
| Class: | Echinoidea | 
| Subclass: | Euechinoidea | 
| Infraclass: | Irregularia | 
| Superorder: | Atelostomata von Zittel, 1879 | 
| Orders | |
The Atelostomata are a type of sea urchins. They are distinguished from other sea urchins by their irregular shape and the absence of a feeding lantern. The group includes the well known heart urchins, as well as some less familiar and extinct forms.