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Crown-of-Thorns starfish

Acanthaster planci


The crown-of-thorns is the second largest sea star in the world and is a corallivore, a carnivorous predator that preys on reef coral polyps. Outbreaks of crown-of-thorns has been blamed for widespread reef destruction.


Spotted during a night dive at Dive and Trek house reef. Thankfully did not spot others so there would seem to be no indication of an outbreak. Bonus find was a commensal shrimp Periclimenes soror hiding among the starfish's thorns (picture 3).

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Eric Noora
Eric Noora 9 years ago

Unfortunately yes Argybee. I think 2 years ago there was a massive outbreak here.

Mark Ridgway
Mark Ridgway 9 years ago

Are these often a problem in Philippines?

Eric Noora
Spotted by
Eric Noora

Batangas, Philippines

Spotted on Jan 21, 2012
Submitted on Feb 12, 2012

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