Spirularia is an suborder of marine

cnidaria Cnidaria ( ) is a phylum under kingdom Animalia containing over 11,000 species of aquatic invertebrates found both in fresh water, freshwater and marine environments (predominantly the latter), including jellyfish, hydroid (zoology), hydroids, ...

ns, tube-dwelling anemones, in the

class Class, Classes, or The Class may refer to: Common uses not otherwise categorized * Class (biology), a taxonomic rank * Class (knowledge representation), a collection of individuals or objects * Class (philosophy), an analytical concept used d ...

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. These anemones dwell in parchment-like tubes immersed in soft sediment, and have two whorls of tentacles, the outer tentacles being much longer than the inner ones.

References

Ceriantharia Anthozoan orders {{anthozoa-stub