| Aspect: | A relatively short mass of randomly branching colonies that can take wide variety of shapes. Usually yellow brown, but also green. |
| Population: | Common |
| Notable feature: | Branches look like fingers. The entire structure is covered in a spectacularly dense array of translucent and hair-like stinging polyps. |
| Environment: | Usually atop boulders, at depths of around 10 metres or more. |
| Behaviour: | The barely visible hair-thin polyps can inflict very painful skin burns even through light conctact. |