Is this the same as bug 24854?
Have you tried purging? http://en.wikipedia.org/wiki/WP:Purge

zillbugga wrote:

(In reply to comment #1)

Is this the same as bug 24854?
Have you tried purging? http://en.wikipedia.org/wiki/WP:Purge

Yes. The image has been edited by AnonMoos (thank you!) to remove excess metadata and convert to RGB; the thumb of the revised version displays correctly. I've performed null edits and appended ?action=purge to the url on both the image file page and the article page. The problem persists, the thumbnail on the page is still on a black ground, as is the thumb of the previous version of the image.
Sorry, I have no idea if this is the same as bug 24854. I read the account of that before posting, but it seemed not identical. Principally, that bug is fixed; this one is not.

(In reply to zillbugga from comment #2)

(In reply to comment #1)

Is this the same as bug 24854?
Have you tried purging? http://en.wikipedia.org/wiki/WP:Purge

Yes. The image has been edited by AnonMoos (thank you!) to remove excess
metadata and convert to RGB; the thumb of the revised version displays
correctly. I've performed null edits and appended ?action=purge to the url
on both the image file page and the article page. The problem persists, the
thumbnail on the page is still on a black ground, as is the thumb of the
previous version of the image.
Sorry, I have no idea if this is the same as bug 24854. I read the account
of that before posting, but it seemed not identical. Principally, that bug
is fixed; this one is not.

Looks like a combination of that bug, with some problems involving not replacing old versions of the thumbnail with the new one. Should be fixed now. If you have any more problems with the file, please re-open the bug and let us know