The Green Sea Anemone (Anthopleura xanthogrammica) is a marine (saltwater) anemone in the Actiniidae family. It is also known as the Giant Green Anemone, the Giant Tidepool Anemone, or the Rough Anemone. It is an animal, not a plant.
The Green Sea Anemone is a broad, flat, disc with its mouth in the centre. It is bright green when exposed to sunlight, and dark-green or brown when not exposed to sunlight. It has short, conical tentacles arranged in rows of six or more, which is called the crown of tentacles. The crown surrounds its oral disc (mouth). The tips of the tentacles can be pointed or blunt.
It measures about 17 centimetres (7 inches) wide and 30 centimetres (12 inches) tall. The crown of tentacles can be up to 25 centimetres (10 inches) wide.
The Green Sea Anemone is native to the Pacific Oean, from Alaska to southern California and Panama. It prefers inter-tidal zones of shallow cold water, such as reefs. It likes sandy or rocky shoreline pools and lagoons.
It can move slowly, using its basal disc, but usually it is still, attached to a rock. Therefore, it is mostly sessile (not moving).
It eats algae, mussels, sea urchins, crabs, and plankton. It uses its stinging cells in its tentacles to protect itself from predators. Its main predators include sea stars (starfish) and sea snails.
The Green Sea Anemone lives a solitary life. Sometimes it is seen in groups of less than 14 individuals.
The female lays eggs in the water. When they hatch into larvae, the larvae float and drift in the sea until fully grown. When fully grown adults, they become benthic – living on the bottom of the ocean.
Photographer: Martina Nicolls
Martina Nicolls: SIMILAR BUT DIFFERENT IN THE ANIMAL KINGDOM