Photo of two species of urchins in Hawaiian coral reef
Diadema and pencil urchins
- Scientific name:
- Diadema urchin: Diadema setosum
- Pencil urchins: Heterocentrotus mammillatus
- Hawaïan name:
- Diadema urchin: ina
- Pencil urchins: Punahu
The diadema urchin has black or white sharp spines reaching 10 to 30cm long. They live in tropical coral reefs like Hawaii. The pencil urchins is typical of central Pacific. It is identifiable to its red colour and its pencil-like spines.