Basket star
Basket stars are brittle stars, close relatives of starfish you might be more familiar with.
They have ten arms which each branch multiple times into progressively finer and more delicate tendrils. They are typically a dull blue-grey with dark stripes on their arms and small, black-ringed knobs on their central disc. They can grow very large, reaching over half a metre across.
Basket stars typically anchor their central disc onto sea fans or other tall corals situated high up in reefs, and hold their arms outstretched to catch passing prey. The fine tendrils on their arms can interlock, forming a basket-like trap.
When not feeding, basket stars can pull their tendrils and arms towards their central disk for protection.
They are found only on the South African coast, from the Cape Peninsula to Algoa Bay.