The Christmas tree worm is found in coral environments. The marine worm resembles a Christmas tree, with a central tube and "arms" (radioles) that form two spiraling structures. Although the shape is similar to that of twin fir trees, the colors are more vibrant. The worms are less than 2 inches long and are commonly found in bright shades of blue, yellow and pink.
The Life Cycle
The Christmas tree worm has a biphasic life cycle, meaning the cycle has two distinct parts. The larval phase begins the life cycle. Worm larvae feed exclusively on plankton. This phase lasts for a short time, from less than a day to several weeks. The larva locates a home on the coral and transforms into an adult, beginning the second phase. The adult builds a burrow in the coral, where it remains for life.
The life-span of a Christmas tree worm depends on the quality and endurance of the coral habitat. Under ideal circumstances the worms will live for 20 to 30 years. In areas with disappearing reef habitat, their lives are much shorter. Domestic environments are difficult to maintain and the worms' life-span varies greatly among tanks.
The two primary requirements for a long life are coral and plankton. The Christmas tree worm burrows its body within the coral and extends its tree branch "arms" outside to breathe and gather food. Outside of plankton, coral and good water quality, the worms have no requirements. Reproducing their habitat in home aquariums is difficult because the worms do not always take to artificial coral.
Christmas tree worms reproduce without leaving the burrow. The worms do not burrow on top of each other, but maintain a distance for breeding, males releasing sperm and females releasing eggs into the same general area. All the worms in an area do this around the same time to increase the odds of successful reproduction. A sperm fertilizes an egg in open water and a larva is born.
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