This is a watercolour painting of a European peacock (Aglais io). The inner side of the wings show bright colours and contrasted patterns.
<a href="//commons.wikimedia.org/wiki/User:Lisa_Nicvert" class="mw-redirect" title="User:Lisa Nicvert">Lisa Nicvert</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>