Cerianthus sp. (Cnidaria, Anthozoa, Ceriantharia, Cerianthidae), antipathula larva, width 750 µm, Helgoland 03.2016. 1:26 min. Antipathula is a specialized larva of the tube anemones, developing from the planula. Inside three pairs of septae develop and four tentacles surrounding the mouth. Later on more septae and tencales develop to form the so-called cerinula. This larva settle on the ground, forming a tube in which the sea anemone can be retracted. Video can be used for teaching.