<p>Diodora variegata (Sowerby II, 1862) - exterior view of a variegated keyhole limpet shell, 1.45 cm long.  Anterior to the top and posterior to the bottom.
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Family Fissurellidae - limpets use their radulae to scrape algae from hard substrates.  They typically occupy rock intertidal shorelines.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/47445767@N05">James St. John</a>
CC BY 2.0
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/jsjgeology/16004835509/">Diodora variegata (variegated keyhole limpet) (San Salvador Island, Bahamas) 1</a>