Hi Cristoph,
The body is not artificial, it's real but very old (it's a butterfly out of a collecting made in 1885) and turned white by a unknown reason.
I can't make a photo of the underside 'cause it's glued and I don't think it's wise to try to make him separated from the paper. Because as you can see I tried it a time ago, and I dameged the left wing
Greetings wessel herrewijnen