Wednesday, November 10, 2010
November 10, 2010 : Christmas Tree Worm
Christmas Tree Worm
Spirobranchus giganteus, commonly known as Christmas tree worms, are small, tube-building polychaete worms belonging to the family Serpulidae.
The worm is aptly named; Both its common and Latin names refer to the two, chromatically-hued spiral structures that are most commonly what is seen of the worm by divers. In actuality, these multicolored spirals are merely the worm's highly-derived respiratory structures.
The worms's most distinct features are the two "crowns" that are shaped like Christmas-trees. These "crowns" are actually highly modified prostomial palps which are specialized mouth appendages of the worm. Each spiral is actually composed of feather-like tentacles called radioles, which are heavily ciliated which allows any prey that are trapped in them to be transported straight towards the worm's mouth. While they are primarily feeding structures, S. giganteus also uses its radioles for respiration. It is because of this that the structures are commonly called "gills".
Christmas-tree worms are widely distributed throughout the world's tropical oceans. They have been known to occur from the Caribbean to the Indo-Pacific.