Christmas Tree worm (spirobranchus giganteus) is a tube-building worm that lives in the stony coral. They have beautiful crowns that shaped like Christmas tree with bright color feather tentacles (radioles). These worms are regularly seen in tropical sea water like in the Caribbean and Indo-Pacific. They are very sensitive to movement and lights. They react very fast by retracting their radioles inside their tubes. For this reason I have not been able to capture their pictures perfectly with their top to make them look like Christmas Trees.
The tube of the worm is lined with appendages that aid the worm in mobility. The worm does not move outside its tube and the appendages do not help the worm to swim. Sincerely I have never seen the worm outside of the coral, so I have no clue about its appendages appearance. The worm itself is very small with average length of 3.8 cm. But it is easy to spot because of its colorful radioles. Its radioles colors are varied from red, purple, yellow and blue. Very pretty! The radioles help the worm in filtering the water particles and plankton for food.
The female and male reproduce by releasing sperm and eggs into the water. I think I managed to capture this moment on my image – just take a look at below picture then you will see there were blue particles floating into the water. Not sure if these particles were eggs or sperms or something else…
This is my last post in 2014 for Diveadvisor. I promise to submit more articles and pictures! Wishing Diveadvisor Team and community a wonderful holiday - Merry Christmas for those who celebrate the festive and Happy New Year!