Nepenthes junghuhnii is a tropical pitcher plant

Pitcher plant

Pitcher plants are carnivorous plants whose prey-trapping mechanism features a deep cavity filled with liquid known as a pitfall trap. It has been widely assumed that the various sorts of pitfall trap evolved from rolled leaves, with selection pressure favouring more deeply cupped leaves over...

 belonging to the genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 Nepenthes

Nepenthes

The Nepenthes , popularly known as tropical pitcher plants or monkey cups, are a genus of carnivorous plants in the monotypic family Nepenthaceae. The genus comprises roughly 130 species, numerous natural and many cultivated hybrids...

. This species has been the source of much confusion since its discovery. The taxon originally named N. junghuhnii by John Muirhead Macfarlane

John Muirhead Macfarlane

John Muirhead Macfarlane was a Scottish botanist. He was born and educated in Scotland, where he occupied several different academic positions at the University of Edinburgh before emigrating to the United States to assume a professorial chair at the University of Pennsylvania in 1893. He held...

 has never been formally published (Henry Nicholas Ridley

Henry Nicholas Ridley

Henry Nicholas Ridley CMG , MA , FRS, FLS, F.R.H.S. was an English botanist and geologist.Born at West Harling Hall, Norfolk, England...

's N. junghuhnii is a heterotypic synonym of N. singalana

Nepenthes singalana

Nepenthes singalana is a highland Nepenthes pitcher plant species native to the island of Sumatra. It is most closely related to N. diatas and N. spathulata.-Taxonomy:...

). In 1994, taxonomist Jan Schlauer described N. junghuhnii as a "rather dubious species based on insufficient specimens". It appears to be most closely related to N. bongso

Nepenthes bongso

Nepenthes bongso is a tropical pitcher plant endemic to Sumatra, where it has an altitudinal distribution of 1000–2700 m above sea level. The specific epithet bongso refers to the Indonesian legend of Putri Bungsu , the spirit guardian of Mount Marapi.The species was formally described by Pieter...

and N. spathulata

Nepenthes spathulata

Nepenthes spathulata is a tropical pitcher plant native to Java and Sumatra, where it grows at elevations of between 1100 and 2900 m above sea level. The specific epithet spathulata is derived from the Latin word spathulatus, meaning "spatula shaped", and refers to the shape of the...

. Nepenthes junghuhnii has not been relocated in the wild since the collection of the type specimen.

Herbarium

Herbarium

In botany, a herbarium – sometimes known by the Anglicized term herbar – is a collection of preserved plant specimens. These specimens may be whole plants or plant parts: these will usually be in a dried form, mounted on a sheet, but depending upon the material may also be kept in...

 specimens named N. junghuhnii were collected in the Batak

Batak (Indonesia)

Batak is a collective term used to identify a number of ethnic groups predominantly found in North Sumatra, Indonesia. The term is used to include the Toba, Karo, Pakpak, Simalungun, Angkola and Mandailing, each of which are distinct but related groups with distinct, albeit related, languages and...

 region of North Sumatra

North Sumatra

North Sumatra is a province of Indonesia on the Sumatra island. Its capital is Medan. It is the most populous Indonesian province outside of Java. It is slightly larger than Sri Lanka in area.- Geography and population :...

 near Lake Toba

Lake Toba

Lake Toba is a lake and supervolcano. The lake is 100 kilometres long and 30 kilometres wide, and 505 metres at its deepest point. Located in the middle of the northern part of the Indonesian island of Sumatra with a surface elevation of about , the lake stretches from to...

.

In his 1928 monograph "The Nepenthaceae of the Netherlands Indies

The Nepenthaceae of the Netherlands Indies

"The Nepenthaceae of the Netherlands Indies" is a seminal monograph by B. H. Danser on the tropical pitcher plants of the Dutch East Indies, North Borneo, the Malay Peninsula, and eastern New Guinea...

", B. H. Danser

B. H. Danser

Benedictus Hubertus Danser , often abbreviated B. H. Danser, was a Dutch taxonomist and botanist...

wrote of this species:

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. I have not seen any of these plants and therefore I am not quite certain about them; however, in H. B. there are other plants, collected by Junghuhn in Sumatra and named N. Junghuhnii by Macfarlane, and it seems evident, that these plants may be identical with those in the Kew Herbarium. About the specimens from G. Kerintji, which, according to Ridley, are "undoubtedly the same species", I dare, of course, not say the same. However, the two numbers in H. B. named by Macfarlane seem to be not wholly identical. The first of the above mentioned plants is a form, certainly intermediate between N. sanguinea and N. singalana. The coarse stems and the large leaves are those of N. sanguinea, the pitchers are smaller than usually are those of N. sanguinea, their shape approaches that of the pitchers of N. singalana and the inflorescences are quite like those of the latter species. The second plant mentioned above is perhaps a piece of an identical plant, though it shows other characters. It is a fragment of the lower portion of a climbing stem; this stem and its leaves are like those of the first mentioned plant, but the pitchers differ from those of N. sanguinea only by the toothed interior margin of the peristome. When the latter character had been absent, I should not have hesitated to record N. sanguinea as occurring in Sumatra; also the provenance of the two mentioned plants from probably the same habitat has kept me from doing this. Of course it is possible, that both plants of Junghuhn represent a new species, but since the material at hand shows only characters intermediate between two species already known and between many related species intermediate forms have been found, I prefer to distinguish also these plants as such. It is very improbable that it is a hybrid, since pure N. sanguinea has not been found in Sumatra, and from the region where Junghuhn collected his plants N. singalana too has not been recorded. 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.