Indo-Pacific Rock-boring Urchin (<i>Echinometra mathaei</i>)
<a rel="nofollow" class="external text" href="https://www.inaturalist.org/users/42472">Robert Webster</a>
CC BY-SA 4.0
<a rel="nofollow" class="external free" href="https://www.inaturalist.org/photos/257850997">https://www.inaturalist.org/photos/257850997</a>