Juvenile Sweetlips. The young of this species are continuously moving in a manner similar to some flatworms. It is thought to be protective behavior since some flatworms are poisonous.
<a href="//commons.wikimedia.org/wiki/User:Nhobgood" title="User:Nhobgood">Nhobgood</a>
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<span class="int-own-work" lang="en">Own work</span>