Tube anemones live inside a self-produced tube and can withdraw into it, the tube consists of a fibrous material that consists of secreted mucus and threads of nematocyst-like organelles, the so-called ptychocysts.
Tube-dwelling Anemone Ceriantharians have a tentacle crown, which consists of two turns of significantly different sized tentacles.
The outer wreath is made up of large tentacles that extend outward. These tentacles taper towards the tips and are mainly used for feeding and defense. The smaller inner tentacles are held more erect than the larger lateral tentacles and are used for food manipulation and ingestion.