[2][3] Nepenthes pitopangii was discovered by the British veterinarian Jonathan Newman during a birdwatching expedition through Lore Lindu National Park, Central Sulawesi, in September 2006.

[3][5] Newman came across the plant "[w]hile trying to get closer to a roosting Diabolical Nightjar [Eurostopodus diabolicus]", and initially thought it was N. eymae,[5] another Sulawesi species that produces similarly shaped upper pitchers.

Further habitat photographs of N. pitopangii were posted online in January 2008 by Alfindra Primaldhi, who found the plant independently, having not seen Newman's report.

[6] In July 2007, Stewart McPherson and Greg Bourke visited the plant and determined that it represented a previously unknown species.

[7] McPherson returned to the site with Ch'ien Lee in April 2008 to make further observations of the plant in preparation for its formal description.

[7][8] During these field trips, McPherson climbed three mountains near to the type locality, but was unable to find any additional specimens of N. pitopangii.

[2][9] The holotype of N. pitopangii, RP 2054, was collected by Rahmadanil Pitopang on May 30, 2007, from Lore Lindu National Park in Sulawesi, Indonesia.

[3] This was proved correct when a small colony of around a dozen N. pitopangii was discovered in March 2011 by Andreas Wistuba, Joachim Nerz, Urs Zimmermann, and Heiko Rischer.

[4] The only individual of this species at the type locality is a large male plant with numerous branched stems reaching up to 2 m in length.

[3] Stewart McPherson observed only four terrestrial pitchers of N. pitopangii during his field studies at the type locality and their description is therefore based on this very small sample size.

Unlike the specimen at the type locality, these plants do not appear to be united by a single rootstock, having instead grown from individual seeds.

Based on observations at the new site, it appears that N. pitopangii only remains in the rosette stage for a short time before transitioning into a scrambling vine.

However, the most obvious differences are in the pitchers; the lower traps at the new locality vary significantly between individuals, but none show the same colouration as the type specimen.

It is known from two localities: a single, multi-stemmed specimen grows in a remote area of Lore Lindu National Park, Central Sulawesi, and a small population has been recorded from the summit of a minor ridge in the southern part of the Minahassa Peninsula.

[2][3][4] The population discovered in 2011 consists of around a dozen plants growing at 1400 m altitude in patchy, exposed, mossy montane forest, among stunted vegetation.

Nepenthes pitopangii at the new locality were found to grow in close association with moss, both as terrestrial plants and as epiphytes on branches and logs.

[4] No natural hybrids have been recorded at the type locality,[3] but a putative cross with N. tentaculata was observed by Urs Zimmermann at the new site.

[3] Nepenthes pitopangii appears to be most closely related to N.glabrata, a highland species also endemic to Sulawesi but not recorded from the local area.

[3] The upper pitchers of N. pitopangii may bear a superficial resemblance to those of N. eymae, N. flava, N. inermis, N. jacquelineae, N. talangensis, N. tenuis, and certain forms of N. maxima.

[3][4] It is unlikely to be a natural hybrid involving N. glabrata since the closest known population of that species is more than 50 km from the type locality of N. pitopangii.

However, all recorded natural hybrids with these species exhibit petiolate leaves and typically have triangular lids with appendages on their lower surface.