The Christmas tree worm, known scientifically as Spirobranchus giganteus, is a tube-building worm native to tropical oceans between the Caribbean and Indo-Pacific. The worms’ most distinct features are two “crowns” shaped like Christmas trees.
The multicolored spirals are highly derived structures for feeding and respiration.
Christmas tree worms average about 1.5 inches in length, and their radioles can have a diameter of up to 1.5 inches.
The images above were capture off the coast of St. Vincent in the Caribbean. More images from Saint Vincent and the Grenadines can be found here.