About Spirobranchus corniculatus (Grube, 1862)
Commonly known as the Christmas tree worm, Spirobranchus corniculatus (Grube, 1862) is a species with very vibrant coloration that changes based on depth, camouflage, and as a scare tactic. Bright spiral rings wrap around its body segments, also called radioles, and this species can have more than 200 segments in total. It has an unusually large body, reaching up to 45 mm (1.8 in) in length and 0.5 mm (0.020 in) in width. Spirobranchus corniculatus occurs in the tropical Indo-Pacific, inhabiting depths between 3 m (9.8 ft) and 30 m (98.4 ft). It is mostly found across the Eastern hemisphere, ranging through Southeast Asia, the Indian Ocean, the central Pacific, and northern Australia. This worm lives on corals, and can be found growing on almost every coral species. It specifically associates with corals such as Porites lobata, which are typically found in Hawaiian waters.
