The book WMF Ikora & Myra Gläser does a pretty good job of including full catalogues for lesser series such as Medusa, Perlmutter, Perlora, etc...
I've looked over the catalogues properly, and this shape does not pop up in any of them. Also, there appears to be nothing quite so transparent in any of the decorative treatments used in the Myra / Perlmutter series so it being a piece that falls between the catalogues seems unlikely.