[2] Herbarium specimens informally named N. junghuhnii by Macfarlane were collected by Junghuhn in the Batak region of North Sumatra, near Lake Toba.

[1] The specimens of N. singalana that Ridley used to describe N. junghuhnii originated from a collection by Harold Ernest Robinson and Cecil Boden Kloss on Mount Kerinci, in the Sumatran province of Jambi.

[1] In his 1928 monograph, "The Nepenthaceae of the Netherlands Indies", B. H. Danser wrote of this taxon:[4] N. Junghuhnii is based upon plants, collected by Junghuhn in Sumatra, named as such by Macfarlane in the Kew Herbarium and seen by Ridley, and with which the latter author identified specimens from G. Kerintji.

As is obvious from a letter written by Macfarlane and extant in the Leiden Herbarium this author intended to make a description of N. Junghuhnii for Koorders to be published in his Plantae Junghuhnianae lneditae, but apparently it had not come to that.

The publication of Ridley, not written in Latin, is invalid from a nomenclatorial point of view.Danser treated N. junghuhnii as a possible natural hybrid between N. singalana and N. sanguinea.