The body of A. bifida is a concave disc surrounded by ten pinnately divided arms giving it a fern-like appearance.
The arm colour is variable, ranging from yellow or pink to deep purple, sometimes spotted or blotched, and the pinnules are usually paler or white.
It may be confused with the rather similar Antedon petasus but that species is usually larger with up to 50 cirri, looks neater and does not have ridges on the undersides of its arms.
[2][3][4] Antedon bifida is primarily found on the coasts of north west Europe, the range extending from the Shetland Islands south to Portugal.
Small particles adhere to the mucus they extrude and the smaller third foot helps to bundle these together to form a bolus.
The female produces a mucus net and protects the developing embryos by holding her arms together in what is described as brooding behaviour.
After about five days, the eggs hatch into free-swimming larvae which soon settle on a solid surface and attach themselves with a short stalk.