Aristolochia palmata is often overlooked in cultivation as it morphologically resembles A. onoei and A. shimadae very much considering floral characteristics. The only distinctive feature to separate A. palmata from its congeners is the highly digitate foliage which - in my opinion - is completely unreliable as subject to environmental conditions.

 

Nevertheless I will be separating this morph from its closest relatives for now - more research is definitely necessary to unravel the taxonomic relationships of the Siphisia species inhabiting the islands of the East China Sea.