Alfindra Primaldhi · CC BY 2.0
About
A notable Sumatran species, *Nepenthes inermis* is easily identified by its unique upper pitchers, which completely lack a peristome. It is a climbing plant that thrives in the montane forests of Sumatra, forming a key part of the local flora.
Field notes
Morphology
The plant is a climbing species with a stem that can reach 7 metres and is cylindrical-triangular in cross section. Leaves are sessile, coriaceous, and lanceolate-spathulate, up to 12 cm long. Lower pitchers are infundibular to ovoid, growing to 8 cm high, with a round, horizontal mouth and a cylindrical peristome bearing indistinct teeth. The unique upper pitchers are larger, growing to 9 cm high and 5 cm wide, and are characterized by a very long, narrow, cuneiform lid and the complete absence of a peristome.
Distribution & habitat
Endemic to the Indonesian island of Sumatra, specifically found in the provinces of West Sumatra and Jambi. It has an altitudinal range of 1,500–2,600 metres (4,900–8,500 ft) above sea level, growing both epiphyte in mossy forest and terrestrially in upper montane vegetation.
Ecology
The pitchers function as both pitfall and flypaper traps, utilizing an extremely thick, mucilaginous pitcher liquid that coats the inner surfaces. This viscous fluid not only traps flying insects, particularly Nematocera and Brachycera, but also acts as a lubricant, allowing prey to slide into the pitcher cup. It is also suggested that glands on the lid secrete compounds that intoxicate visiting insects.
History & etymology
First collected on September 7, 1918, by H. A. B. Bünnemeijer on Mount Talang. B. H. Danser formally described *N. inermis* a year later in his monograph, noting that the species was easily distinguishable by its peculiar pitchers without a peristome and with a very narrow lid.
Conservation
Least concern (IUCN Red List)
Habitat
- Altitude
- 1,500–2,600 m
- Altitude Class
- highland
- Native To
- Sumatra, Indonesia
- IUCN Status
- Least Concern
Taxonomy
- Described
- 1928
- Authority
- Danser
Cultivation
- Difficulty
- intermediate
Borneo Exotics 1 listing
View all →
Crossed Nepenthes inermis with another species?
Register the cross — if it's not yet documented you'll be the first contributor. If someone already registered it, you'll be redirected to add your photo.