Tube-Growing Polychaetes (Sedentary)- Christmas Tree Worms

 

 

 

 

 

This unique creature is known as Spirobranchus giganteus, or more commonly, the Christmas Tree Worm. With its unique shape and enormous variety, it is very popular among scuba divers and potential salt-water aquarium owners for its visual appeal.

 

 

 

As a sedentary annelid (passive body structure), the worm's actual body is actually embedded in the coral or rock. Its plumes sift through the nearby currents for nutrients and other essentials, and also conduct the oxygen-carbon dioxide exchange with its surroundings.

 

 

 

The unique double spiral structure and 'feathers' ensure the maximum surface area to do perform both functions. The plumes are also hypersensitive, sucked instantly into the worm's burrow if something as irregular as an overhead shadow occurs. They will reemerge about a minute later, carefully testing the surrounding waters before coming back out completely.