Crypsis

Reteterebella queenslandia relies on crypsis for survival. They spend all of their known life under coral boulders/coral rubble in sandy substrates of coral reef lagoons. They burrow into the sand or attach to the underside of coral boulders. R. queenslandia also accumulates sand particles to create tubing for protection. The tubes are constructed out of particles of sand that are too large to eat and mucus. Their role in defence is not clear as the worms are found in hard to reach places, limiting the additional protection gained by this tube. However the tube may protect from small predators that are able to move through the benthos.
	A cluster of spaghetti worms after a coral boulder has been overturned. Several tubes are empty due to the organisms swimming through the coral boulder and back down to the benthos.
	The tentacles of R. queenslandia are the only parts visible from the surface. When touched or disturbed, they are able to retract these tentacles beneath the coral bolder, protecting themselves from predators. R. queenslandia also collects sand particles to build protective casings. It uses its tentacles to collect grains of sand, coating them in mucus and gluing them together to form a protective tube. The feeding tentacles are also sensitive to light. When the worm is disturbed, the tentacles actively seek out areas which have low light to hide in. This behaviour ceases once the worm has found a dark crevice to hide in. This indicates that the photoreceptors are used to find habitat and not to avoid predation.
Pair of R. queenslandia retracting their buccal tentacles after their crevice was overturned.