Gansu mudan(paeonia Rockii)
Gansu mudan “Xibei” just means “Northwest China” = (presumably) “Northwest China Cultivar Group” = all NW tree peony (mudan) cultivars, not just those with a purple blotch in the centre of the flower. “Ziban” means something like “having a dark centre“; “Ziban mudan” means all peonies with a dark-centred flower, that is, P. rockii and