A Black Swallowtail larva (<i><a href="//commons.wikimedia.org/wiki/Papilio_polyxenes" title="Papilio polyxenes">Papilio polyxenes</a></i>) showing its osmeterium.
<a href="//commons.wikimedia.org/wiki/User:Meganmccarty" title="User:Meganmccarty">Megan McCarty</a>
CC BY 3.0
<span class="int-own-work" lang="en">Own work</span>