<p>Among cephalopods, oegopsid squids dominate the pelagic, oceanic environment. Diversity at the family and generic levels is very high with 24 families and 69 genera. Although pelagic, some species are consistently associated with and some occasionally sit on the ocean floor. </p> <h4>Diagnosis</h4> <p>Decapodiforms ... </p> <ul> <li> without cornea covering eyes.</li> <li>with a gladius.</li> </ul>