In his description of the Bornean species N. campanulata, botanist Shigeo Kurata suggested that it may be closely related to N. inermis.
Nepenthes clipeata | Nepenthes bokorensis | Nepenthes | Nepenthes rajah | Nepenthes mantalingajanensis | Nepenthes klossii | Nepenthes faizaliana | Nepenthes epiphytica | Nepenthes abgracilis | Nepenthes rigidifolia | Nepenthes mira | Nepenthes khasiana | Nepenthes kerrii | Nepenthes deaniana | Nepenthes cid | Nepenthes aristolochioides | Nepenthes viridis | Nepenthes ovata | Nepenthes mirabilis | Nepenthes spathulata | Nepenthes rhombicaulis | Nepenthes pitopangii | Nepenthes × kinabaluensis | Nepenthes holdenii | Nepenthes × harryana | Nepenthes dubia | Nepenthes burbidgeae | Nepenthes bellii | A skeletal revision of ''Nepenthes'' (Nepenthaceae) | ''Nepenthes smilesii'' from Kirirom National Park |