A floating seed ball in the Colombian Amazon, and claimed to be edible.  The species is found in tropical northern South America.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/92252798@N07">Dick Culbert</a> from Gibsons, B.C., Canada
CC BY 2.0
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/92252798@N07/17225435155/">Naucleopsis ulei</a>