A typical sea anemone is a sessile polyp attached at the base to the surface beneath it by an adhesive foot, called a basal or pedal disc, with a column-shaped body topped by an oral disc. Most are from 1 to 5 cm (0.4 to … See more

Unlike other cnidarians, anemones (and other anthozoans) entirely lack the free-swimming medusal stage of their life cycle; the polyp produces eggs and sperm, and the fertilized egg develops into a planula larva, which deve… See more

A sea anemone is capable of changing its shape dramatically. The column and tentacles have longitudinal, transverse and diagonal sheets of muscle and can lengthen and contract, as well as bend and twist. The g… See more

Sea anemones and their attendant anemone fish can make attractive aquarium exhibits, and both are often harvested from the wild as adults or juveniles. These fishing activities significantly impact the population… See more

Most Actiniaria do not form hard parts that can be recognized as fossils, but a few fossils of sea anemones do exist; Mackenzia, from the Middle Cambrian Burgess Shale of Canada, is the oldest fossil identi… See more