Crown-of-thorns starfish
Acanthaster planci
- Scientific name
- Acanthaster planci
- Group
- Echinoderms (starfish, urchins...)
- Rarity
- Rare
- Where to see it
- Indo-Pacific & Red Sea
- Conservation status (IUCN)
- Not evaluated
Did you know?
The crown-of-thorns starfish feeds on live coral by digesting the polyps outside its own body, and can grow up to 21 arms covered in venomous spines. During population outbreaks, it can devastate large stretches of coral reef within just a few months.
What defines this group — Echinoderms (starfish, urchins...)
Starfish, urchins and sea cucumbers: a five-fold symmetry found nowhere else in the animal kingdom.
- The body is arranged in fives around a centre: no head, no front, no back.
- They move on hundreds of tube feet driven by water under pressure.
- Many regrow a lost arm; some starfish can rebuild themselves from a single one.