The Nepenthaceae of the Netherlands Indies
B. H. Danser united the species "[w]ith some hesitation" in his 1928 monograph "The Nepenthaceae of the Netherlands Indies". He suggested that "N. villosa" is a stunted form of "N. edwardsiana" from higher elevations, which flowers at a "juvenile stage of development". Danser acknowledged that the indumentum of "N. villosa" is more dense than that of "N. edwardsiana", but noted that it "is a difference only of degree".