Leptosynapta inhaerens - Holothurian <a href="https://en.wikipedia.org/wiki/Leptosynapta_inhaerens" class="extiw" title="en:Leptosynapta inhaerens"><i>Leptosynapta inhaerens</i></a>, syn. Synapta inhaerens © Alfred Brehm - Public domain - Wikimedia Commons