| Aspect: | Looks like a single (no branches) barbed wire winding its way up into the water. The "barb" is in fact a dense pattern of radially deployed polyps along the central structure of this black coral. 
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| Population: | Common, usually on the slopes of deep-plunging reefs. 
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| Notable feature: | Looks dark overall, but under flashlight reveals a brown or orange stem form which a continuous stream of white polyps radially protrudes. 
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| Environment: | Generally along reef slopes from 20 metres on. 
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| Behaviour: | Polyps retract if accidentally touched. 
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