Nepenthes aristolochioides /nɪˈpɛnθiːz ærɪˌstɒloʊkiˈɔɪdiːz/ is a tropical pitcher plant endemic to Sumatra, where it grows at elevations of 1800–2500 m above sea level.

The specific epithet aristolochioides is formed from the genus name Aristolochia and the Latin ending -oides, meaning "resembling".

The holotype, Meijer 6542, was collected on that date from Mount Tujuh (Tudjuh) in Jambi at an elevation of 2000 m. It is deposited at the National Herbarium of the Netherlands (L) in Leiden, but is in relatively poor condition.

[6] That same year, taxonomist Jan Schlauer questioned the supposed lateral pitcher mouth of N. aristolochioides in email correspondence with botanist Matthew Jebb, who was preparing a revision of the genus at the time.

[7] Schlauer wrote that he had examined a specimen of this species (Meijer 7426) and that the seemingly vertical insertion of the pitcher mouth might be a result of the preservation process, whereby the traps had become "compressed along their longitudinal axes".

Together with Katrin Hinderhofer, Nerz organised a field trip to Sumatra in June 1996 and was successful in rediscovering N. aristolochioides in the wild.

[2][8][9] Joachim Nerz wrote a detailed description of the species for an issue of the Carnivorous Plant Newsletter published the following year.

[4] The next major treatments of the species appeared in Cheek and Jebb's updated 2001 work, "Nepenthaceae";[10] Charles Clarke's Nepenthes of Sumatra and Peninsular Malaysia, also published in 2001;[5] and Stewart McPherson's two-volume Pitcher Plants of the Old World, released in 2009, which included colour photographs of specimens from a newly discovered locality.

[10] It is gradually attenuate towards the base, becoming partly amplexicaul (clasping the stem for one-third to half of its circumference)[10] and, rarely, slightly decurrent.

They arise from the leaf base and occasionally along the length of the midrib, and are restricted to the distal third[10] to two-thirds of the lamina, where they run parallel to the laminar margin.

[5] A pair of wings (≤9 mm wide) runs down the front of the pitcher, either covering the length of the trap's ventral surface or being restricted to the upper part only.

[4] The peristome, which is up to 20 mm wide,[5] is expanded, incurved, and internally flattened, forming an "entrance corridor" similar to a lobster pot.

[3] It has no appendages, but bears numerous nectar glands, which are scattered quite evenly across the entire lower surface of the lid.

[3][14] In 2001, Charles Clarke wrote that the species was only known from Mount Tujuh in Jambi, although specimens collected by Herbert Christopher Robinson and Cecil Boden Kloss labelled as being taken from "Mt.

It grows with the former in montane forest and swamps dominated by Pandanus species that line the shoreline of a crater lake.

The altitudinal distribution of N. gymnamphora on Mount Tujuh (1800–2100 m) overlaps that of N. aristolochioides, but no natural hybrids have been observed.

Despite the fact that all known populations of the species lie within Kerinci Seblat National Park, it is severely threatened by over-collection, because its unique pitcher morphology makes it particularly sought-after.

This is not due to a lack of potential inhabitants; pitchers of N. singalana, which grow alongside N. aristolochioides, support large populations of such organisms.

It is thought that the structure of the traps may serve to disorientate emerging adults and so infaunal species avoid colonising them.

The lower pitchers of this species frequently develop embedded in Sphagnum moss, with only the top of the traps visible.

[4] Along with N. klossii, N. aristolochioides is the only species in the genus to employ domed pitchers with translucent patches that allow sunlight to illuminate the interior.

[5] This is supported by the fact that most of the prey caught by N. aristolochioides consist of small flies, which are attracted to bright light sources.

[13] The central role of the translucent dome in the prey trapping mechanism of N. aristolochioides is supported by experimental evidence.

In one study, pitchers whose domes were covered with red celluloid filters showed a threefold decrease in Drosophila trapping efficiency as compared to unaltered pitchers and those shaded at the front with the same filters (flies are red-blind and most sensitive to the UV, blue, and green wavebands).

[12] Nepenthes aristolochioides produces extremely thick, mucilaginous pitcher liquid, which coats the entire inner surfaces of the traps in a thin film.

[3] Similarly viscous pitcher fluid is also found in seven other closely allied Sumatran species: N. dubia, N. flava, N. inermis, N. jacquelineae, N. jamban, N. talangensis, and N. tenuis.

The two taxa also differ somewhat in growth habit; N. talangensis occurs only terrestrially and is a weak climber, whereas N. aristolochioides occasionally grows as an epiphyte and climbs high into the forest canopy.

[10] In 2001, Charles Clarke performed a cladistic analysis of the Nepenthes species of Sumatra and Peninsular Malaysia using 70 morphological characteristics of each taxon.

[4] The unique adaptations of these taxa might represent an example of convergent evolution, whereby two organisms that are not closely related independently acquire similar characteristics while evolving in separate, but comparable, ecosystems.

This hybrid can be distinguished from N. aristolochioides on the basis of its narrow, cylindrical peristome and oblique mouth, as opposed to almost vertical in the latter.