Comprehensive Description

	Reteterebella queenslandia is a sedentary polychaete commonly referred to as a spaghetti worm. It is found throughout the inner reef area, but occurs in higher densities in the sandy inner reef areas, where it shelters under live coral boulders and clumps of macro-algae. Individuals tend to clump together and colonise the same boulder, where several individual organisms can be found on a single boulder. R. queenslandia is characterised by a large mass of white tentacles on the anterior of the worm (Hartman, 1963). These tentacles are used in both sensory systems and feeding. R. queenslandia has a sophisticated sensory system for a sedentary polychaete. The tentacles are highly muscularised ceolomic cavity extensions and possess both mechanoreceptors and photoreceptors (no information exists on the presnence of chemoreceptors). Mechanoreceptors are used as a defence mechanism, causing the buccal tentacle mass to retract when touched, whereas the photoreceptors found at the tip of each tentacle are primarily used for finding shelter and cervices to hide in.
Reteterebella queenslandia living in a protective tube underneath a coral boulder.
As mentioned previously, the tentacles are also used for deposit feeding. Sand particles are collected by tentacles and passed along by a ciliated groove. The sand particles are then sorted at the mouth/pharynx where: small particles are ingested; medium sized particles are used to build a protective casing for the polychaete; and large particles are ejected (Matther and Bennett, 1993). The mouth and pharynx are highly muscularised but lack teeth.  R. queenslandia also has three pairs of highly branched branchiae located anteriorly next to the mouth. R. queenslandia is a very cryptic species and in reef systems, the only visible part is their tentacles, which extend from rock boulders. Because of this crypsis, it is assumed that they do not possess any highly toxic chemicals for defence, instead relying solely on crypsis for defence against predators. Crypsis is achieved by negatively phototactic sensory cells on the tips of the feeding tentacles. R. queenslandia use these sensory cells to seek out shelter when they are disturbed. These tentacles are able to respond quickly to light but are only sensitive to blue light.
	Buucal tentacles of R. queenslandia extending onto the sand to feed during low tide.
	Very little is known about the reproductive biology of R. queenslandia. Currently, only adult specimens have been recorded at Heron Reef. We are unaware of how frequently they reproduce, the method that they reproduce (brooders or broadcast spawners) or how far they are able to disperse. It is also possible that several closely related species are found at adjacent reefs but are yet to be formally identified.