Nepenthes lamii is a tropical pitcher plant endemic to New Guinea, where it grows at an altitude of up to 3520 m above sea level, higher than any other Nepenthes species. Although once confused with N. vieillardii and previously regarded as conspecific with the closely related N. monticola, it is now recognised as a distinct species. The specific epithet lamii honours Dutch botanist Herman Johannes Lam, who made one of the earliest known collections of this species. Botanical history Early collections Herman Johannes Lam, after whom the species is named, made a number of collections of N. lamii during the Van Overeem Expedition of 1920. He collected both male and female floral material on October 17, 1920, on the flanks of Doorman Top (now known as Mount Anggemuk), West Papua, at an elevation of 3250 m (or 3200 m). These specimens are collectively designated as Lam 1637. Lam made a further collection of N. lamii on the following day, October 18, this time from 3520 m on Doorman Top. It represents the uppermost altitudinal limit for this species and for all Nepenthes. This material also consists of both male and female parts and is designated as Lam 1654. Both of Lam's specimens represent greatly stunted, dwarf plants. They are deposited at Herbarium Bogoriense (BO), the herbarium of the Bogor Botanical Gardens. Grouping with N. vieillardii The first author to describe specimens of N. lamii was B. H. Danser in his seminal 1928 monograph, "The Nepenthaceae of the Netherlands Indies". Danser interpreted specimens of N. lamii as representing an outlying population of N. vieillardii (previously recorded only from New Caledonia) and used two specimens of N. lamii (Pulle 843 bis and Lam 1654) to illustrate the latter species (figure 26 in his monograph). In addition to the specimens mentioned above, Danser also listed Docters van Leeuwen 10834 as New Guinean material of what he identified as N. vieillardii. Danser explained his interpretation of N. vieillardii as follows: N. Vieillardii has only been recorded from New Caledonia and the Isle of Pines up to the present, but the materials collected by the latter expeditions have shown, that at least in the western part of New Guinea it is not rare, in the latter country it varies more than in New Caledonia but it seemed impossible to me to distinguish separate species. Most alike the plants of New Caledonia are the number Pulle