Common name: Pencil Urchins

Cidaridae, commonly known as Pencil Urchins, are a family of sea urchins characterized by their thick, blunt spines that resemble pencils. They are found in various marine environments from shallow reefs to deep-sea habitats. Pencil Urchins are known for their hardy nature and ability to adapt to different conditions, making them a suitable choice for reef aquariums. They play a beneficial role in the tank by grazing on algae, helping to keep the aquarium clean. However, their spines can be sharp and may harm more delicate tank inhabitants.

1. 
   Common name: Pencil Urchin

   Scientific name: Eucidaris metularia
2. 
   Common name: slate pencil urchin

   Scientific name: Eucidaris tribuloides
3. 
   Common name: Slate Pencil Urchin

   Scientific name: Goniocidaris tubaria
4. 
   Common name: pencil urchin

   Scientific name: Phyllacanthus imperialis
5. 
   Common name: Cidaroid Sea Urchin

   Scientific name: Plococidaris verticillata
6. Common name: Crown-spined Pencil Urchin

   Scientific name: Prionocidaris baculosa
7. 
   Common name: Pencil Sea Urchin

   Scientific name: Prionocidaris bispinosa
8. 
   Common name: red lance urchin

   Scientific name: Stylocidaris affinis