Scientific name: Ophiothrix fragilis
Size: Up to 20cm across, but usually far smaller in rockpools
Colour: Brown or black, sometimes more colourful
Habitat: Under rocks, in both rockpools and deeper water
- They use their bristly arms to catch food that drifts by.
- In deep water, they can form congregations, with up to 10,000 Brittlestars per square metre.
- Their spindly arms are very fragile, so care needs to be taken when handling them.