Giant Green Anemone (Anthopleura xanthogrammica)
If A. xanthogrammica is exposed to proper amounts of sunlight, it can appear bright green when submerged under water.
When not submerged, it appears dark green or brown. This is because the anemone tends to close up and “droop” and its now exposed column is actually dark green and slightly brown, but the hidden tentacles and oral disk are bright green.
Photosynthetic algae, zoochlorellae, and the dinoflagellates, zooxanthellae, live in epidermis and tissue of the gut of A. xanthogrammica forming a symbiotic relationship. This relationship can provide nutrients to the anemone via photosynthesis and contribute to the bright green color of the oral disk and tentacles…
(read more: Wikipedia) (photo: Stan Stebs)
