Crown-of-thorns starfish substrates with their arms and, when offered a choice of substrates, tend to settle on coralline algae, which they will subsequently feed on. In the classic pattern for echinoderms, the bilaterally symmetrical larva is replaced by a pentamerously symmetrical stage at metamorphosis, with the latter's body axis bearing no relationship to that of the larva. Thus the newly metamorphosed starfish are five-armed and are 0.4–1 mm diameter. (Note the size of the tube feet relative to the size of the animal.) They feed on the thin coating layers of hard encrusting algae (coralline algae) on the undersides of dead coral
Crown-of-thorns starfish it eradicates the bulk of the starfish in a given area, human divers can move in and remove the survivors. Field trials of the robot have begun in Moreton Bay in Brisbane to refine its navigation system, according to Queensland University of Technology researcher Matthew Dunbabin. There are no crown-of-thorns starfish in Moreton Bay, but when the navigation has been refined, the robot will be used on the reef. Crown-of-thorns starfish The crown-of-thorns starfish, "Acanthaster planci", is a large starfish that preys upon hard, or stony, coral polyps (Scleractinia). The crown-of-thorns starfish receives its name from venomous thorn-like spines that