Nepenthes Nomenclature
When you dive into the world of Nepenthes, you quickly notice their names are … well, complicated to say the least. But there’s method to the madness! To the newcomer, the long Latin labels may seem intimidating, but they follow clear rules. Once you grasp the basics of nomenclature, you'll not only be able to read these names but also uncover the stories of the plant’s heritage, discovery and even cultivation history.
Like most plants, Nepenthes are named using two international systems:
The International Code of Nomenclature for algae, fungi, and plants (ICN)
The International Code of Nomenclature for Cultivated Plants (ICNCP)
Both systems help ensure clarity and consistency when describing plants across the world.
1. The Basics
Every living organism is classified according to binomial nomenclature - a two part scientific name consisting of the genus and the species.
Example: Homo sapiens (Homo = genus; sapiens = species)
Example: Nepenthes villosa (Nepenthes = genus; villosa = species)
The genus name may also be abbreviated to a single capital letter followed by the species name.
Example: Nepenthes lowii is synonymous with N. lowii
Formatting Rule: The genus is capitalised & both genus and species are italicised
2. Horticultural Hybrids
Pitcher plants hybridize readily and growers love to experiment with crosses.
Rule: The first species is always the female, the second is the male.
Primary (simple) hybrids involve just two species
Example: Nepenthes truncata x macrophylla
Complex hybrids involve three or more species:
Example: Nepenthes truncata x (naga x bongso)
To keep track of these lineages, hybrids use parentheses first followed by brackets second and braces third:
Parentheses ( )
Brackets [ ]
Braces { }
Example: Nepenthes [(lowii x boschiana) x veitchii] x {[(lowii x veitchii) x truncata] x platychila}
3. Natural Hybrids
Natural hybrids follow the same formatting rules as species (italicized names) but include a small '“x” before the hybrid name & without a space prior.
Example: Nepenthes xtrusmadiensis (natural hybrid of Nepenthes lowii x macrophylla)
Example: Nepenthes xkinabaluensis (natural hybrid of Nepenthes rajah x villosa)
Example: Nepenthes xharryana (natural hybrid of Nepenthes edwardsiana x villosa)
Note: Before modern naming systems, some early horticultural hybrids were given simple names written in italics with a capitalised hybrid name. These older names can be confusing, since sometimes they referred to a single plant and other times to all offspring of a cross.
Example: Nepenthes Mastersiana is an old Victorian hybrid between Nepenethes sanguinea and Nepenthes khasiana
4. Grexes and Cultivars
A grex refers to all the progeny from a single horticultural cross. Nurseries sometimes use grex names for sales convenience.
Example: Nepenthes Gothica
Example: Nepenthes veitchii (m) or Nepenthes veitchii (k)
However, serious collectors usually prefer the full parentage for accuracy.
Within a grex, particularly outstanding individuals may be named as cultivars (cultivated varieties).
Example: Nepenthes Sabre ‘Dark Cherry’
Example: Nepenthes veitchii ‘Geoff Wong’
Example: Nepenthes naga ‘Paul Barden’
Example: Nepenthes veitchii ‘Candy Dreams’
Formatting Rule: Cultivar names are placed in single quotes, not italicized
5. Variants and Clones
Variant is a term used to describe different plants from the same grex that are genetically unique but related (i.e. seed grown plants)
Clones are genetically identical plants produced via tissue culture (micropropagation), leaf cuttings or basal divisions.
This distinction matters - while one grower may have Nepenthes veitchii (m) may differ significantly from a sibling grown by someone else
6. Unnamed species
When new plants are discovered but not formally described, they are provisional written using sp. nov. meaning ‘species novel’. This is usually followed by a descriptor (e.g. location) that is not italicised.
Example: Nepenthes sp. nov. Kemiri
Example: Nepenthes sp. nov. Pseudoklossii
7. Other abbreviations
spp. = multiples species within the genus
var. = variety
Example: Nepenthes carunculata var. robusta - noted for its broader leaves, thickened tendrils and a wide peristome on nearly black pitchers.
Example: Nepenthes mirabilis var. echinostoma - famous for its bizarre exaggerated peristome with tentacle-like outgrowths unlike typical N. mirabilis.
Example: Nepenthes rafflesiana var. alata - again form with extremely wide bulbous lower pitchers adorned with frilled tendrils and elegant lighter uppers with a raised striped peristome.
aff. = affinitive (similar to, or resembling, but not quite the same as another species)
Example: Sometimes plants are sold under one name - say N. bongso - but once grown out, they may show traits closer to N. naga or an hybrid of the two. In this case. the correct way to label the plant would be Nepenthes aff. naga, indicating that it most closely resembles N. naga without being confirmed as that species.
syn. =synonymous (an older or alternative scientific name that refers to the same taxon as the accepted name)
Example: Before being reinstated as a separate species, Nepenthes graciliflora was treated as a synonym of N. alata. At the time, a plant we would now identify as Nepenthes graciliflora would have been simply described as Nepenthes alata (syn. N. graciliflora)
8. Hybrid Variability and Species Integrity
Horticulturalists have observed an important pattern: primary hybrids usually show little variability in offspring.
Hence, if significant variation is seen, it may suggest that one or more parent is not a “true” species but carries introgression (i.e. hybrid ancestry)
For example, Borneo Exotics’ Nepenthes burbidgeae | Pig Hill | BE-3848 has long been speculated to show introgression from N. rajah, explaining its unusually red colouration compared to other N. burbidgeae.
9. Why not just use common names?
Common names may be easier to remember, but they’re often ambiguous or misleading.
For example, the “Queen pitcher plant” could refer to:
Nepenthes ventricosa × robcantleyi ‘Queen Malani’
N. robcantleyi ‘Queen of Hearts’
N. xtiveyi (aka ‘Red Queen’’)
Scientific names, by contrast, are precise and universal — they avoid confusion and ensure clear communication among growers, researchers and enthusiasts worldwide.
