Here is for example one link which tells that N. mira and rajah are closely related:
http://www.cascadecarnivores.com/pro...roducts_id=104
Very interesting concerning the phylogenetc relationship of the nep species can be found here
http://pitcherplants.proboards34.com...ay&thread=5183
Concerning this link they are related but not so closely.
Also I found information concerning the relationship on some german language websites.