It's then time to clear up a long-time misunderstanding.
Nepenthes are carnivorous pitcher plants. They have normal leaves, but at the end of each leaf there is an insect trap called pitcher. Every pitcher is topped by a lid. While the pitcher develops, from little to large, the lid is closed. Once the pitcher is fully mature, the lid opens and reveals the trap's entrance. By the way, the lid doesn't move to catch prey, it's there mainly to prevent rainwater from entering the trap.
Nepenthes have two types of pitchers. The lower pitchers at the base of the plant, often wider and globose, and the upper pitchers on the climbing stem, usually elongated. If you look at an upper pitcher (or at an elongated lower pitcher) that is not fully developed, and thus with a closed lid, it looks very much like a penis.
This is the case with more or less all 170 Nepenthes species.


In 2014 someone posted on YouTube a video with the title "Nepenthes holdenii, penis plant", or something like that. It showed some young girls on Mount Bokor, in Cambodia, holding the upper pitchers of Nepenthes bokorensis. They were all laughing about how the pitchers looked like penises. Whoever posted the video, didn't know the exact name of the plant, but he probably managed to find the genus name Nepenthes, he probably looked for Nepenthes + Cambodia, and he probably found links referring to another, far-less-known Cambodian species called Nepenthes holdenii, hence the title. The problem is that the video got millions of views (it was later removed and then posted again by others). Since then, millions of people have been looking for (and posting about) the rare penis plant called Nepenthes holdenii. Quite a distortion of reality. Yet, the crowd still spills onto the web on a regular basis, and thousands of people spill onto this website, which has a page about the Nepenthes of Indochina and hosts the original description of Nepenthes holdenii. Imagine people with pitchforks in front of my gate, shouting: "We want the Penis Plant!". Here are two screenshots from the video.



So, back to the real world. I do understand the curiosity. Never mind that the genus Nepenthes includes tens of incredibly beautiful species, never mind that most of them are going extinct because we are 8 billion and half of the planet is covered with plantations, never mind how hard many people are working to study these plants in the wild. People want to see the penis. So, to begin with, don't look obsessively for Nepenthes holdenii, look for "Nepenthes" and play with the words "penis" (just the word mate), "closed pitcher/trap" or "immature pitcher/trap". Then, here is an exemplificative collage: