I had several butterfly images on istock, paper kites and painted ladies as well as several other varieties.  I painstakingly researched the names and keyworded them appropriately.  My images were tagged, though for inappropriate keywords because I had the words "painted" and "lady" in the keywords or "Paper" and "kite".  Since the image had neither lady or paint, nor paper nor kite istock removed them.  I have also had keywords removed for other things such as an emerald cut diamond had the word emerald removed because it was not an emerald but a diamond.  I had an image of a child waiting at a bus stop.  The word bus and stop were removed.