Nepenthes Pilosa - Botanical History

Botanical History

Nepenthes pilosa was discovered in 1899 by Javanese plant collector Amdjah during the Nieuwenhuis Expedition, on which Amdjah also made the first collection of N. ephippiata.

Nepenthes pilosa was formally described in 1928 by Dutch botanist B. H. Danser in his seminal monograph "The Nepenthaceae of the Netherlands Indies". Danser designated Amdjah 491 as the type specimen and also referred Amdjah 499 to the species. Both specimens were colleced on January 28, 1899, from Bukit Batu Lesung, a mountain located near the center of Kalimantan, at an altitude of approximately 1600 m. Danser also listed a "very doubtful" male specimen (Mjöberg 46) under his description of N. pilosa. This specimen was collected by Eric Mjöberg between October and December 1925, from Bukit Batu Tiban at an altitude of 1700 m. Danser wrote of Mjöberg 46:

"It is only one leaf with upper pitcher, and an inflorescence not certainly belonging to the same plant; the pitcher is not congruent with that of number Amdjah 491 and this is the reason I have not completed the description with that of the male inflorescence."

All three specimens mentioned by Danser are deposited at Herbarium Bogoriense (BO), the herbarium of the Bogor Botanical Gardens.

In the latter half of the 20th century, wild plants of N. chaniana were almost universally identified as N. pilosa. One example of this is the treatment of N. chaniana by Bertram Evelyn Smythies in 1965, in the proceedings of the UNESCO Humid Tropics Symposium, which was held in Kuching two years earlier. In his 1997 monograph, Nepenthes of Borneo, botanist Charles Clarke noted that several authors had noticed discrepancies between the type material of N. pilosa and plants identified as this species in the field:

"he illustration of the type of N. pilosa in Danser (1928) does not correspond very well with plants identified as N. pilosa in East Malaysia (J. Schlauer, pers. comm.). M. Jebb (pers. comm.) also notes that the upper pitcher on the type is unusual "

Despite this, Matthew Jebb and Martin Cheek did not distinguish the East Malaysian plants from N. pilosa in their monograph published the same year. Similarly, in Pitcher-Plants of Borneo (1996), Anthea Phillipps and Anthony Lamb treated plants from Mount Alab, Crocker Range, as N. pilosa, following the interpretation of J. R. Turnbull and A. T. Middleton in an unpublished mimeograph report from 1981.

Although he treated plants from East Malaysia as N. pilosa in his 1997 monograph, Charles Clarke doubted their conspecificity. He visited the type locality of N. pilosa in 2004, making the first collection of this species since 1899. In July 2006, Clarke revisited wild populations of N. pilosa on Bukit Batu Lesung to confirm its status as a distinct species. Later that year he, together with Ch'ien Lee and Stewart McPherson, published the formal description of N. chaniana. This revised circumscription means that N. pilosa is endemic to Kalimantan, while N. chaniana is native to Sabah and Sarawak. As such, virtually all plants in cultivation up to that time under the name N. pilosa actually represented N. chaniana.