Christmas Tree Worm Spirobranchus giganteus
Many large coral heads in tropical waters are decorated with Christmas tree worms, which occur in a huge variety of colors. The worm lives in a calcareous tube buried in the coral and extends neat, twin spirals of feeding tentacles above the coral surface. If disturbed, the worm pulls back into its tube in a fraction of a second. For added safety, the Christmas tree worm can also plug its tube with a small plate called an operculum.
- Class Polychaeta
- Length Up to 1 in (3 cm)
- Depth 0–100 ft (0–30 m) or more
- Habitat Living coral heads
- Distribution Shallow reef waters throughout the tropics