scaly-foot gastropod
... that the scaly-foot gastropod is the only known living animal that uses iron sulfides in its skeleton?
... that the <b id="mwCEY"><a href="./Scaly-foot_gastropod" id="mwCEc" rel="mw:WikiLink" title="Scaly-foot gastropod">scaly-foot gastropod</a></b> <i id="mwCEg">(pictured)</i> is the only known living animal that uses <a href="./Iron_sulfide" id="mwCEk" rel="mw:WikiLink" title="Iron sulfide">iron sulfides</a> in its skeleton?