The tip of this rasp fern frond (<i>Doodia media</i>) displays the pink colour characteristic of young fronds in this species. The colouration is caused by a flavonoid that protects the plant from ultraviolet radiation. Photo taken on Tiritiri Matangi Island, near Auckland, New Zealand.
<a href="//commons.wikimedia.org/wiki/User:Avenue" title="User:Avenue">Avenue</a>
CC BY-SA 3.0
<span class="int-own-work" lang="en">Own work</span>