Facts: The Christmas Tree Worm

The Christmas tree worm is a tube-building polychaete worm that lives on tropical coral reefs around the world. Each worm has two brightly colored crowns that protrude from its body, resembling Christmas trees. They come in a variety of colors and are easily spotted, despite their small size. The crowns are composed of hair-like appendages, radiating from the worm's central spine. These appendages are used for respiration and for feeding. They typically feed on microscopic plants or phytoplankton floating in the water. Christmas tree worms are sedentary. They exist in symbiotic relationships with coral. Most of the worm's segmented body is anchored in a burrow that it bores into live coral. A worm will create a calcium carbonate tube within the coral where it can live for up to 40 years. The worms are typically less than 2 inches long. Each of these worms possesses a well-developed digestive system, circulatory system, and nervous system. They are extremely sensitive to movements and changes in light. When startled, they rapidly retract into their burrows. When they withdraw their plumes, they close their tube with a hard trap called an operculum. The operculum also has a large calcium carbonate spine. This protects the worms from predators like butterflyfish. They are thought to protect their coral hosts from predators, like crown-of-thorns starfish, by pushing away the creature's tubed feet. For more marine facts, click the SUBSCRIBE button!!