This weeks Photo of the Week is an Anchor coral (Euphyllia ancora, Euphyllia paraancora or parancora). It was actually shot in December 2010, but has taken several months to identify.
Belonging to the mushroom coral family, it is normally found in the Indo-West Pacific in Japan, Maldives, Fiji, Tonga, Solomon Islands, and around to Australia including the Great Barrier Reef.
Anchor Coral is very similar to Hammer Coral which have hammer or “T” shaped polyp tips. Anchor corals lack the “T” shape, and have semi-circular or sausage shaped tips.
Euphyllia ancora are one of the coral species that extend long sweeper tentacles, often used as a means of defense against other encroaching corals. Their white tips contain a concentration of stinging cells (nematcysts) that help to capture small prey and defend themselves against predators.
They live in colonies with polyps that retract into the skeleton, and inhabit both reef slopes and reef bottoms down to depths down to 40 m.