Echinopsis spachiana
... that the flower of the cactus Echinopsis spachiana mainly opens at night?
... that the flower of the cactus <i id="mwAfQ"><b id="mwAfU"><a class="mw-redirect" href="./Echinopsis_spachiana" id="mwAfY" rel="mw:WikiLink" title="Echinopsis spachiana">Echinopsis spachiana</a></b></i> <i id="mwAfc">(pictured)</i> mainly opens at night?