The life cycle of an anemone is not generally typical for the members of the Cnidarian Phylum. Since they are polymorphic, one of the major differences in the anemone life cycle is the fact that they do not go through a medusoid stage. While the classes Scyphozoa and Hydrozoa have both polyp and medusoid forms, the members of the class Anthozoa lack this medusoid stage completely.  As with other Cnidarians, anemones start their life cycles as fertilized eggs which develop eventually into planula larvae.

The planula larvae can be either planktonic larvae, which feed independently, or lecithotrophic larvae, which means that they feed on the yolk. The planula larvae will typically develop in the open ocean, where they grow into juvenile anemones. This process, however, leaves the juvenile anemones lacking tentacles, and they therefore remain free-swimming individuals until they come to settle on some form of substrate. Once settled, the anemone will continue to develop, and tentacles will form. They can then begin the process of feeding and reproducing more anemones. Their life cycle continues when this new anemone, being hermaphroditic, either releases sperm or eggs into the environment and to another anemone, and fertilization begins yet again to form another planula larvae.

Anemones  typically remain solitary animals throughout their life, instead of taking on a colonial form as many other Anthozoans tend to do in their life cycles. The average known lifespan of a sea anemone is approximately 50 years.

Home  Taxonomy   Distribution  Ecology  Physiology  Reproduction  References

Copyright 2002 Karlee Markovich