Scientifically that are calledspirobranchus giganteus, but they are better known by their colloquial name — Christmas tree worm. The worm is so called not because they feed on fig trees but because they look like them.
![christmas-tree-worm-10](https://lh3.googleusercontent.com/-IeIN5_tYX48/VnuO9t18JGI/AAAAAAABJ2M/C5EDwPuArnw/christmas-tree-worm-10%25255B5%25255D.jpg?imgmax=800)
The Christmas tree worm doesn’t like to move about much. Once they find a good place on a live calcareous coral, they burrow a hole and live their for the rest of their lives, occasionally emerging from their home to catch passing plankton with their fully extended plumes. They are very sensitive to disturbances and will rapidly retract into their burrows at the slightest touch or passing shadow.
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