The large anemone with a coloured column that holds most of the anemonefish on a reef.
Disc to about 1 m across when fully open, with long, evenly thick tentacles ending in slightly swollen tips, and a column that is bright blue, purple, red, green or white and is usually the quickest way to identify the species — the other large anemones here have dull or hidden columns. It contracts into a ball around the column when disturbed.
It hosts the ocellaris clownfish and the pink anemonefish, sometimes both at once, and carries porcelain crabs and anemone shrimps as well. Like the reef corals it depends on symbiotic algae for much of its food and bleaches white when stressed by heat, taking its resident fish with it. It sits on coral heads and slope faces in current-exposed positions. Recorded from about 3 to 30 m.
Ratings are per location: 1 means found on most dives that look for it, 5 means a handful of records. Where enough dives have been logged the figure is calculated from them; otherwise it is an editorial estimate, and says so. We publish habitat and destination, not the dive site.
