The ultra violet thing isn't that terribly uncommon on flowers, but I would think leaves are another "animal". Did the literature say anything about testing for pitcher plant flowers and/or different species? Love to see the the original work if you have a link.
My initial wondering with the pitcher plant is: why doesn't the UV color extend inside the pitcher?
But with further thought, it's more likely that once the an insect is attracted to the lip, scent might take over as the primary lure.
