Aggregating Anemone
Scientific Name: Anthopleura elegantissima
Category: other
Brief Description
A common marine cnidarian found in the intertidal zone, often appearing as a squishy, greyish-green lump when closed at low tide.
Characteristics
When closed, it resembles a small, leathery, or squishy mound covered in bits of shell and sand. When open underwater, it displays a central mouth surrounded by numerous short tentacles with pink or purple tips.
Habitat
Rocky intertidal zones, specifically attached to rocks, boulders, and dock pilings.
When to Find It
Visible year-round, most easily observed during low tide.
Conservation Status
N/A
Ecological Role
A major predator of small invertebrates and a host for symbiotic algae (zooxanthellae) which provide the anemone with nutrients via photosynthesis.
Easily Confused With
Giant Green Anemone (Anthopleura xanthogrammica), which is much larger and does not live in dense clonal colonies. Moonglow Anemones (Anthopleura artemisia) are also similar but usually buried in sand.
Observation Tips
Look for them in the mid-intertidal zone of Puget Sound. Avoid stepping on them; though they feel like stones when covered in shell, they are living animals.
Interesting Facts
This species is famous for its 'clone wars'; colonies are often made of genetically identical individuals that will physically attack non-clone neighbors to maintain territory.
User Notes
Puget Sound