A 15-day old <a href="https://en.wikipedia.org/wiki/Siamese_fighting_fish" class="extiw" title="wikipedia:Siamese fighting fish">Siamese fighting fish</a> (<i>Betta splendens</i>) with a severe infestation of <i>Oodinium sp</i>. parasites (<a href="https://en.wikipedia.org/wiki/Velvet_(fish_disease)" class="extiw" title="wikipedia:Velvet (fish disease)">Velvet disease</a>, also known as dust disease).
<a href="//commons.wikimedia.org/wiki/User:ZooFari" class="mw-redirect" title="User:ZooFari">ZooFari</a>
CC BY 3.0
<span class="int-own-work" lang="en">Own work</span>