<p>An Eastern Smooth Boxfish (<a rel="nofollow" class="external text" href="http://www.fishbase.org/Summary/speciesSummary.php?genusname=Anoplocapros&amp;speciesname=inermis"><i>Anoplocapros inermis</i></a>). Pipeline, Port Stephens, NSW
</p><p>Boxfish are covered in hard triangular plates of armour, which make the fish look a bit like a living geodesic dome. The armour offers good protection, but prevents the fish bending its body which makes swimming an effort! The boxfish is able to move its tail thanks to an un-armoured section near the tail which acts as a hinge.
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The armour plates and "hinge" are clearly visible in the large version of this image. They are also visible in <a rel="nofollow" class="external text" href="http://www.amonline.net.au/fishes/fishfacts/fish/ainermisdry2.htm">this photo</a> of a dried Eastern Smooth Boxfish on the Australian Museum web site.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/82825649@N00">Richard Ling</a> from NSW, Australia
CC BY-SA 2.0
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/82825649@N00/1696523207/">Eastern Smooth Boxfish</a>