Waratah anenomes <i><a href="https://en.wikipedia.org/wiki/Actinea_tenebrosa" class="extiw" title="w:Actinea tenebrosa">Actinea tenebrosa</a></i> in a rockpool on the south coast of New South Wales, Australia.  The anenome on the right is closed.
<a href="//commons.wikimedia.org/wiki/User:99of9" title="User:99of9">Toby Hudson</a>
CC BY-SA 3.0
<span class="int-own-work" lang="en">Own work</span>