Spirobranchus corniculatus, commonly referred to as the Indo-Pacific Christmas tree worm, is a species of tube-building annelid fanworms in the family Serpulidae.

[1][2] Belonging to the class Polychaeta, it is recognized for its bristle-like tentacles and the presence of a structure called radioles.

It is widely encountered and recognized for its unique resemblance to a conifer and its diverse array of colors.

[6] The Christmas tree worm inhabits depths of 3–30 m (9.8–98.4 ft)[8] and can also be found living on almost every species of coral.

[5] It is mostly encountered in the eastern side of the globe, spanning Southeast Asia, the Indian Ocean, the central Pacific, and the northern region of Australia.