<i>Neritina reclivata</i>, the olive nerite
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/ictheostega/">ictheostega</a>
CC BY 2.0
image <a rel="nofollow" class="external text" href="https://www.flickr.com/photos/ictheostega/2956196607/">Olive nerite</a> at Flickr. Cropped by (<a href="//commons.wikimedia.org/wiki/User:Snek01" title="User:Snek01">User:Snek01</a>)