Common name: Sea Urchins

Spatangoida, commonly known as heart urchins, are a group of burrowing sea urchins found in soft substrates. Unlike their spherical relatives, they have a distinct heart-shaped form and move through the substrate using their spines as stilts. In reef aquariums, they can help turn over and aerate the sand bed, contributing to a cleaner and more balanced environment. However, they require careful consideration as they can disturb some sediments and sensitive inhabitants.

1. 
   Common name: Lesser Sand Dollar

   Scientific name: Brissus latecarinatus
2. Common name: groove burrowing urchin

   Scientific name: Brissus unicolor
3. 
   Common name: sea-potato

   Scientific name: Echinocardium cordatum
4. 
   Common name: Heart Urchin

   Scientific name: Lovenia elongata
5. 
   Common name: West Indian Sea Egg

   Scientific name: Meoma ventricosa
6. 
   Common name: Starry Blenny

   Scientific name: Metalia spatagus
7. 
   Common name: Purple heart urchin

   Scientific name: Spatangus purpureus