The head of Antarctic krill. Observe the <a href="https://en.wikipedia.org/wiki/light_organ" class="extiw" title="en:light organ">light organ</a> at the <a href="https://en.wikipedia.org/wiki/eyestalk" class="extiw" title="en:eyestalk">eyestalk</a> and the <a href="https://en.wikipedia.org/wiki/nerve" class="extiw" title="en:nerve">nerves</a> visible in the <a href="https://en.wikipedia.org/wiki/antennae" class="extiw" title="en:antennae">antennae</a>, the <a href="https://en.wikipedia.org/wiki/gastric_mill" class="extiw" title="en:gastric mill">gastric mill</a>, the filtering net at the <a href="https://en.wikipedia.org/wiki/thoracopod" class="extiw" title="en:thoracopod">thoracopods</a> and the rakes at the tips of the thoracopods.
Image by <a href="//commons.wikimedia.org/wiki/User:Uwe_kils" title="User:Uwe kils">User:Uwe kils</a>.
CC BY-SA 3.0
<span class="int-own-work" lang="en">Own work</span>