orange-band surgeonfish
... that the orange-band surgeonfish can change colour from dark to light almost instantaneously?
... that the <b id="mwA4U"><a href="./Acanthurus_olivaceus" id="mwA4Y" rel="mw:WikiLink" title="Acanthurus olivaceus">orange-band surgeonfish</a></b> <i id="mwA4c">(pictured)</i> can change colour from dark to light almost instantaneously?