Nepenthes titiwangsa

Nepenthes sp. Titiwangsa (pesonawangsa223) A.Amin, or simplified as N. Pesonawangsa223, is a provisional new species of tropical pitcher plant that thrives on a few summits in the Titiwangsa mountain range. The diagnosis, photographs, and description (of lower pitchers and stems) of N. Pesonawangsa223 are included in a scientific article that contains the taxonomical notes of all 18 published species recorded from Peninsular Malaysia. While working for the publication on its formal taxonomic treatment, the authors decided to initially publish the taxon using the provisional taxonomic label. The interim label provides a working name that can be employed in subsequent scientific discussions and publications, and is viewed as a strategy to promptly communicate the discovery to the scientific community and ensure the authorship of the species. The type locality of the species was visited several times in 2023 and the taxon soon will be formally treated as the 19th species discovered in Peninsular Malaysia. The plant materials were collected from the reserve forest with the permissions from the governing authorities and the type specimens (containing stems with lower and upper pitchers) have been deposited to the University of Malaya Herbarium (KLU) in July 2023. 
==Botanical history==
In the year 2021, Alias Shakri and his team sighted a trap of an unknown species exhibiting flared peristome in the northern part of Peninsular Malaysia. In early 2023, A. A. Tamizi discovered a population of Nepenthes with expansive peristomes (up to 4.5 cm wide), thought to be related to the plant firstly observed by Alias Shakri. Upon closer inspection, the population of this unknown taxon had a bizarre ventral wing formation; four rows of wings immediately below the peristome, which is not reported in any species of Nepenthes where typically only two rows are present. The description of the taxon was published in the same year and treated as a provisional new species.
==Etymology==
The authors have put forth the species name Nepenthes pesonawangsawith the intention of replacing the provisional label N. sp. Titiwangsa (pesonawangsa_223) A.Amin in an upcoming formal species treatment. The epithet is derived from the Malay words 'pesona', meaning 'the charm', and 'wangsa', meaning 'noble lineage' or 'dynasty'. Together, it represents the notion of captivating and exceptionally unique traits exhibited by this taxon, distinguishing it from other pitcher plant species. Additionally, the name rhymes with 'Titiwangsa', the mountain system to which this species is confined.
==Diagnosis and related species==
This species belongs to the N. macfarlanei group for having toothed peristome and fine hairs below the lid, and N. gracillima is considered its most closely related taxon. However, it possesses several prime diagnostic features that establish it as a distinct species from N. gracillima, including; lower pitchers with ventral wings that grow in more than two rows immediately below the peristome (vs. two rows), suborbicular and deeply cordate (reniform) lids (vs. elliptical lids), fine lid abaxial hairs longest at the basal appendage (vs. no basal appendage, hairs longest towards the margin), wide and flared peristomes (3.5-4.5 cm) (vs. peristomes flattened and not expanded), and strongly decurrent leaf base (up to 40 mm) on the lower stems (vs. decurrent angling ca. 3 mm). Only a total of 11 plants have been confirmed so far in several localized mountain peaks (≥1800 m above sea level), indicating a potential classification as a Critically Threatened (CR) taxon.
The six species (excluding N. Pesonawangsa223) within the N. macfarlanei aggregate are N. alba, N. berbulu, N. gracillima, N. macfarlanei, N. sericea, and N. ulukaliana. 
Category:Nepenthes
Category:Plants
Category:Tropical flora