frilled shark
... that the frilled shark may have the longest gestation period of any vertebrate, at three and a half years?
... that the <b id="mwFvI"><a href="./Frilled_shark" id="mwFvM" rel="mw:WikiLink" title="Frilled shark">frilled shark</a></b> <i id="mwFvQ">(pictured)</i> may have the longest <a class="mw-redirect" href="./Gestation_period" id="mwFvU" rel="mw:WikiLink" title="Gestation period">gestation period</a> of any <a href="./Vertebrate" id="mwFvY" rel="mw:WikiLink" title="Vertebrate">vertebrate</a>, at three and a half years?