Spirobranchus is the second largest genus of tube-building annelid fanworms in the family Serpulidae. Members of Spirobranchus are known as Christmas tree worms.

The worms form a calcareous tube which becomes incorporated into their host coral. The prominent features visible externally are a pair of conical spiral radiole bundles ("trees"), and an operculum that closes when they retract into their tube.

The crown of radioles serves for both food-gathering and respiration. "Christmas tree" refers to the tiered, tapered shape, whilst "Spirobranchus" translates to "spiral gill".

Taxonomy and systematics

The type species Spirobranchus giganteus was described by Peter Simon Pallas in 1766 as Serpula gigantea. In 1818, Henri de Blainville separated "S. gigantea de Linné" into a its own genus named in French as "Spirobranche".

Species

The species in the genus (World Register of Marine Species) include:

• Spirobranchus aloni Perry, Bronstein, Simon-Blecher, Atkins, Kupriyanova, ten Hove, Levy & Fine, 2018

• Spirobranchus corniculatus (Grube, 1862)

• Spirobranchus latiscapus Marenzeller, 1885

• Spirobranchus americanus (Day, 1973)

• Spirobranchus arabicus Monro, 1937

• Spirobranchus baileybrockae Pillai. 2009

• Spirobranchus cariniferus (Gray, 1843)

• Spirobranchus coronatus Straughan, 1967

• Spirobranchus corrugatus Straughan, 1967

• Spirobranchus decoratus Imajima, 1982

• Spirobranchus dendropoma Mörch, 1863

• Spirobranchus eitzeni Augener, 1918

• Spirobranchus gardineri Pixell, 1913

• Spirobranchus giganteus (Pallas, 1766)

• Spirobranchus incrassatus Krøyer in Mörch, 1863

• Spirobranchus kraussii (Baird, 1865)

• Spirobranchus lamarcki (Quatrefages, 1866)

• Spirobranchus latiscapus (Marenzeller, 1885)

• Spirobranchus lima (Grube, 1862)

• Spirobranchus maldivensis Pixell, 1913

• Spirobranchus minutus (Rioja, 1941)

• Spirobranchus murrayi Pillai, 2009

• Spirobranchus nigranucha (Fischli, 1903)

• Spirobranchus paumotanus (Chamberlin, 1919)

• Spirobranchus polycerus (Schmarda, 1861)

• Spirobranchus polytrema (Philippi, 1844)

• Spirobranchus pseudopolytremus Pillai, 2009

• Spirobranchus richardsmithi Pillai, 2009

• Spirobranchus spinosus Moore, 1923

• Spirobranchus taeniatus (Lamarck, 1818)

• Spirobranchus tenhovei Pillai, 2009

• Spirobranchus tetraceros (Schmarda, 1861)

• Spirobranchus triqueter (Linnaeus, 1758)

• Spirobranchus zelandicus Pillai, 2009

• Spirobranchus zibrowii Pillai, 2009

References

Bibliography