<p>Scientific Name: <i>Chrysothrix candelaris</i> (L.) J. R. Laundon
Common Name: Gold Dust Lichen
Certainty: positive (<a rel="nofollow" class="external text" href="http://bornnaturalist.org/notes/20070625#1">notes</a>)
Location: California; Los Angeles; Urban Pasadena
Date: 20070625
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Yes, that is a lichen, not spray paint.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/7147684@N03">Jason Hollinger</a>
CC BY 2.0
<p><a rel="nofollow" class="external text" href="https://www.flickr.com/photos/7147684@N03/991745482/">Gold Dust Lichen</a>
</p>
<ul><li>Uploaded by <a href="//commons.wikimedia.org/wiki/User:Amada44" title="User:Amada44">Amada44</a></li></ul>