Spirularia

Cerianthidae is a family of tube-dwelling anemones in the order Spirularia of the subclass Ceriantharia.

Botrucnidiferidae is a family of cnidarians belonging to the order Spirularia.

Spirularia is a suborder of marine cnidarians, tube-dwelling anemones, in the class Ceriantharia. It is one of the two suborders making up Ceriantharia, and includes two families, Botrucnidiferidae and Cerianthidae, and around 99 species. The two suborders differ in the makeup of their cnidome (the types of cnidocyte present), the relative sizes of the oral discs and the shape and structure of the mesenteries.