Serpulidae Family of Christmas Tree Worms
One Christmas Tree Worm of the Serpulidae Family is found in this website:
Giant Christmas Tree Worm, Spirobranchus giganteus. A representative of the Serpulidae Family of Christmas Tree Worms.
The Serpulidae Family members are commonly known as Christmas Tree Worms, along with earthworms, belong to the Phylum Annelida. Their bodies are composed of ringed segments. Their body cavities are filled with coelemic fluid which, hydrostatically, provides rigidity to the body. Annelids have well-developed circulatory, digestive, and nervous systems. Serpulids are in the Class Polychaeta, which stems from the Greek words meaning “many bristles”. The bristles are chaete, chitinous setae, or spines, that assist the animal with movement, swimming, or anchoring. Most polychaete are free-living, but some live in tubes, burrows, or as parasites inside other animals. Christmas Tree Worms are in the Order Sabella, as such, they are sedentary suspension feeders, and they lack a buccal organ and are unable to reach out with mouth parts to grab food. Instead, they use their tentacles (radioles) to grab plankton from the water column, and then pass the food to their mouth. Polychaete worms in the Order Sabella are tube-dwelling, constructing their tubes either from cemented grains of sediment or from calcium carbonate.
Most Serpulids are primarily found in marine environments. They are found worldwide in polar, temperate and tropical seas. attached to coral, rock, and other hard surfaces. They range in depth from the intertidal zone to very deep-sea trenches. The majority are brightly colored. Large Serpulids reach a maximum of 20 cm (7.9 inches) in length.
Serpulid Christmas Tree Worms inhabit calcareous tubes that are composed of a mix of calcium carbonate and mucopolysaccharides. The tube may be straight or curved, but not spiraled, except at its very beginning. They are characterized by a cone-shaped structure made up of feather-like radioles (branches) at their anterior end that attach to a lobe surrounding the mouth. This structure is known as a branchial crown and used for respiration and food gathering. The setae of the radioles may be smooth or hooked. One radiole in the structure is modified to serve as an operculum (trapdoor) that closes when the animal withdraws into its tube. Christmas Tree Worms have distinct thoracic and abdominal segments and eye spots that vary widely in complexity. The Serpulids are bi-sexual and they reproduce either asexually by paratomy (budding from the posterior end), or sexually. Females cast their eggs into the surrounding water or into a section of the tube and the males follow releasing sperm in the same area. The fertilized eggs mature to planktonic larvae which settle on to hard substrates and begin tube building. From this point forward, they remain confined to their tube. Serpulids are filter feeders that filter plankton from the water column. Once caught, the plankton are swept down a groove, by currents generated by cilia, to the mouth. In turn they are eaten by crabs, fish, gastropods and starfish. Serpulids are very quick to retract into their tube when they sense changes in water movement or light that they associate with a predator. Serpulids are important contributors of calcium to coral reef building; they are also known for being destructive by fouling boat hulls and pipelines. Abandoned Serpulid tubes may break loose and closely resemble sea shells of the Vermetidae Family. The two can be distinguished by Serpulid tubes having a dull interior finish while Vermetids have a glossy interior finish.
There are between three hundred and four hundred members of the Serpulidae Family of which fifty-three species are found along the Pacific Coast of Mexico. Some of these species are non-native, invasive species that were introduced to the area by specimens travelling on the hulls of ships or by shrimp farming.