The plumose sea anemone has a cylindrical body with a broad base that allows it to anchor firmly to various surfaces. Its numerous, slender tentacles form a dense crown when fully extended. Individuals can grow up to 12 inches in height. This species displays a wide range of colors, including white, orange, dark green, brown, gray, red and yellow.

The plumose sea anemone is a circumboreal sea anemone found in the cold waters of the North Atlantic, North Pacific and Arctic oceans.

The plumose sea anemone thrives in diverse marine environments, including rocky reefs, sandy seabeds and even artificial structures such as ship hulls and harbor docks, showcasing its impressive adaptability. It can be found from the intertidal zone to depths of several hundred meters.

As a sessile predator, the plumose sea anemone primarily feeds on plankton and suspended organic particles. Its tentacles contain specialized stinging cells called cnidocytes, which allow it to capture and immobilize prey before ingestion. This anemone also plays a crucial ecological role by filtering water and providing shelter for various marine species.

The plumose sea anemone employs both sexual and asexual reproduction strategies. In sexual reproduction, individuals release their gametes into the water, producing planktonic larvae that eventually settle and transform into adult anemones. Asexual reproduction occurs through budding or binary fission, enabling the species to rapidly multiply and colonize new habitats.

The plumose sea anemone is of particular interest in marine biology and benthic invertebrate ecology due to its diverse morphology and adaptability. Research on this species focuses on its color variations, which provide insights into population dynamics, as well as its defense mechanisms involving the production of toxic substances.