| Nepenthes spathulata | |
|---|---|
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| A lower pitcher ofNepenthes spathulata | |
Scientific classification | |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Order: | Caryophyllales |
| Family: | Nepenthaceae |
| Genus: | Nepenthes |
| Species: | N. spathulata |
| Binomial name | |
| Nepenthes spathulata | |
| Synonyms | |
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Nepenthes spathulata/nɪˈpɛnθiːzˌspæθjʊˈlɑːtə/ is a tropicalpitcher plant native toJava andSumatra, where it grows at elevations of between 1,100 and 2,900 m above sea level. Thespecific epithetspathulata is derived from theLatin wordspathulatus, meaning "spatula shaped", and refers to the shape of thelamina.[5]
One of the first collections ofN. spathulata was made byMaurits Anne Lieftinck. The specimenLieftinck 11 was collected in January 1935[note a] onMount Tanggamus nearLampung,Sumatra, at an altitude of 2,000 m.[5]
Nepenthes spathulata wasformally described byB. H. Danser later that same year,[2] the first of twoNepenthes species described by theDutch botanist following the publication of his 1928 monograph, "The Nepenthaceae of the Netherlands Indies".[6]
The next major taxonomic treatment ofN. spathulata came only in 1986, whenRusjdi Tamin andMitsuru Hotta treated the species in synonymy withN. singalana. The authors also lumped four other species underN. singalana:N. carunculata,N. gymnamphora,N. pectinata, and, by implication,N. densiflora.[4] Many authors now considerN. carunculata to be aheterotypic synonym ofN. bongso andN. pectinata is often equated withN. gymnamphora.[5][7]
OnMount Dempo,Mike Hopkins,Ricky Maulder andBruce Salmon found what they believed to be a new species ofNepenthes. They published an account of their discovery in a 1990 issue of theCarnivorous Plant Newsletter. It reads:[3]
We headed back up the line and went to G. Dempo as we wanted to climb at least one unknown mountain. On this mountain, we found a new species related to the highland Sumatran species by its leaf shape, stem shape and inflorescence, but its upper pitchers are slightly similar toN. alata from the Philippines. We gave the nameN. 'dempoensis' after the mountain from which it originated.
The nameN. dempoensis is anomen nudum and thetaxon is now considered conspecific withN. spathulata.[5][8][9]
In 1997, the genusNepenthes was revised in its entirety byMatthew Jebb andMartin Cheek in "A skeletal revision ofNepenthes (Nepenthaceae)". The authors keptN. spathulata as a valid species and designatedLieftinck 11 as itslectotype.[10]
In 2004, aJavan taxon resemblingN. spathulata was discovered by Adrian Yusuf.[11] Two years later, it was given the informal nameN. adrianii/nɪˈpɛnθiːzˌædriˈæniaɪ/ by Batoro, Wartono, andMatthew Jebb,[12][13][14][15] and was treated as a distinct species in the bookTrubus Info Kit: Nepenthes.[16] These plants typically have reddish-green pitchers with red speckles and a red peristome.[17]Nepenthes adrianii is generally considered to be aheterotypic synonym ofN. spathulata.[7][18]
Nepenthes spathulata is a climbing plant. The stem may grow to a height of 5 m but is only up to 8 mm in diameter.Internodes are up to 15 cm long and cylindrical to angular or rhomboid in cross section.[5]
Leaves aresessile to sub-petiolate andcoriaceous in texture. As the name suggests, the lamina isspathulate. It may be up to 30 cm long by 10 cm wide and is graduallyattenuate towards the base. The apex of the lamina is rounded and shortlyacuminate oremarginate. Three to five longitudinal veins are present on either side of themidrib.Pinnate veins are generally indistinct.Tendrils are up to 20 cm long and sometimes have a sub-peltate insertion.[5]
Rosette and lower pitchers gradually or abruptly arise from the end of the tendril. The pitcher cup is ovoid in the lower third to two-thirds, becoming cylindrical and somewhat narrower above.N. spathulata probably produces the largest pitchers of the SumatranNepenthes species; they may be up to 30 cm high and 10 cm wide. A pair of fringed wings (≤25 mm wide) runs down the front of the pitcher. Theglandular region covers the ovoid portion of the pitcher's inner surface;[5] the waxy zone above is well developed.[19] The mouth is round, very oblique throughout, and may be elongated into a short neck. Theperistome is narrow at the front (≤5 mm wide), becoming much wider towards the rear (≤25 mm wide). It is flared at the sides and may be scalloped, although this feature is somewhat atypical of the species as a whole. The inner margin of the peristome is lined with short but distinct teeth.[5] The inner portion of the peristome accounts for around 32% of its total cross-sectional surface length.[19] The pitcher lid oroperculum is ovate, lacks appendages, and is often slightlycordate. Thespur, located near the base of the lid, is usually branched and may be up to 10 mm long.[5]
Upper pitchers are infrequently produced. They are narrowly ovoid in the lowermost quarter to third of the pitcher cup, becoming cylindrical above. They are much smaller than lower pitchers, only reaching 15 cm in height and 3 cm in width. The mouth is approximately round and is not elongated into a neck. It has an oblique insertion. The peristome is also much thinner (≤7 mm wide) and is oftenundulate at the margins. Two pronounced ribs are present in place of wings. In other aspects of morphology, upper pitchers are similar to their terrestrial counterparts.[5]
Nepenthes spathulata has aracemoseinflorescence. Thepeduncle is up to 5 cm long. Therachis may be up to 15 cm long, although it is shorter in female inflorescences.Pedicels are up to 10 mm long and have afiliformbracteole.Sepals areobovate to oblong in shape and up to 4 mm long.[5]
Inflorescences have a denseindumentum of short hairs. Developing pitchers are also densely covered with short hairs, but most of these arecaducous. The stem, lamina and tendrils are virtuallyglabrous.[5]
The stem and lamina are green. Lower pitchers range in colour from light green with a dark purple peristome to yellowish-bronze with a bright red peristome.[5]
Nepenthes spathulata is native to the islands ofJava andSumatra. In Sumatra, it has been recorded from theIndonesianprovinces ofJambi,South Sumatra,Bengkulu, andLampung. Its natural range stretches fromMount Tanggamus in the south toLake Kerinci in the north. It has a wide altitudinal distribution, having been recorded from elevations of 1,100 to 2,900 mabove sea level.[5][20]
Plants growing inmossy forest and lowermontane forest usually have anepiphytic habit, while those from stunted upper montane forest on summit ridges generally occur terrestrially.Nepenthes spathulata is also known to grow terrestrially in high altitudepeat swamp forest nearLake Kerinci, at an altitude of 1,100 m. At this location,N. spathulata grows alongsideN. ampullaria,N. gracilis,N. mirabilis,N. reinwardtiana, andN. tobaica. At least threenatural hybrids ofN. spathulata have been recorded there. TheNepenthes species and hybrids at this site exhibit high levels ofintrogression. The vegetation is dominated by species of the generaRhododendron andMelastoma, as well asorchids andferns. It is very stunted and dense, with few trees exceeding 3 m in height. It is somewhat reminiscent of the highlandheath forests aroundBareo inSarawak,Borneo.[5] Theconservation status ofNepenthes spathulata is listed asLeast Concern on theIUCN Red List.[1]
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The closest relative ofN. spathulata appears to beN. singalana. It differs from this species in having a peristome that is contracted towards the front and very wide at the sides. In addition, it has less prominent peristome ribs and shorter teeth thanN. singalana.[5]N. spathulata has an ovate lid, compared to theorbicular operculum ofN. singalana. Furthermore,N. spathulata has fewer glands on the lower surface of the lid and they are concentrated near the centre.[10]
InJambi, the ranges of both species overlap, as the southernmost populations ofN. singalana meet the northernmost populations ofN. spathulata. Of particular note are plants growing onMount Masurai, which appear intermediate in form between these two species and cannot be definitively assigned to either. These plants exhibit significant morphological variability, particularly in the development of the peristome, with some resemblingN. singalana and othersN. spathulata. Clarke writes that it "is possible that one taxon blends into the other in this region".[5]
Nepenthes spathulata is also allied toN. densiflora, a fact noted byB. H. Danser in his 1940 description of the latter species.[22] However, Jebb and Cheek considered it more likely thatN. bongso, rather thanN. spathulata, is a close relative ofN. densiflora.[10]Nepenthes densiflora can be distinguished fromN. spathulata on the basis of its upper pitchers, which are typicallyinfundibular rather than cylindrical. However, a number ofN. densiflora plants onMount Kemiri are known to produce unusual cylindrical aerial pitchers. Nevertheless, these plants differ fromN. spathulata in producing infundibular lower pitchers.[5]
The herbarium specimensJunghuhn 274 andJunghuhn 275, which were labelled asN. junghuhnii byJohn Muirhead Macfarlane, have pitchers that resemble those ofN. spathulata (as well asN. bongso andN. singalana). However, the poorly knownN. junghuhnii is easily distinguished from these species on the basis of its stronglypetiolate leaf bases.[5]
The upper pitchers ofN. spathulata, which are ovoid in the lower part and cylindrical above, distinguish it from other related species such asN. bongso andN. ovata.[5]
In 2001, Clarke performed acladistic analysis of theNepenthes species of Sumatra andPeninsular Malaysia using 70 morphological characteristics of each taxon. The following is part of the resultantcladogram, showing "Clade 3", which comprisesN. spathulata and three other related species.[5]
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Natural hybrids involvingN. spathulata are relatively rare, as few other species grow sympatrically with it. Seven putative hybrids have been recorded to date, at least three of which are known from a unique highlandpeat swamp habitat aroundLake Kerinci.[5][23]
Nepenthes mirabilis ×N. spathulata is one of the hybrids recorded from the Lake Kerinci peat swamp. The parent species are not known to be sympatric at any other location and so this hybrid is unlikely to occur elsewhere. The pitchers ofN. mirabilis ×N. spathulata are reddish-brown with dark speckles and a bright yellowish-red peristome. It differs fromN. mirabilis in its wider peristome, which bears distinct teeth and more pronounced ribs. FromN. spathulata, it differs in havingchartaceous, sub-spathulate leaves, usually withfimbriate margins.[5]
Nepenthes reinwardtiana ×N. spathulata is also known solely from the peat swamp near Lake Kerinci. LikeN. mirabilis ×N. spathulata, this hybrid is unlikely to occur anywhere else. The lower pitchers are infundibular in the lowermost part, becoming ovoid up to the hip, and cylindrical above. A pair of narrow wings, which may or may not be fringed, run down the front of the pitcher. Upper pitchers are more elongated and less ovoid, with no wings or fringe elements. The peristome is flattened and only slightly expanded. The lid is large and sub-orbicular in shape. The leaves are linear-lanceolate in shape, slightlydecurrent towards the base, and have asessile attachment.[5]
A thirdN. spathulata hybrid withN. tobaica has also been recorded from the Lake Kerinci peat swamp,[5] andN. ampullaria ×N. spathulata is known from the Kerinci region.[23] In addition,N. inermis ×N. spathulata is known fromJambi.Nepenthes gymnamphora ×N. spathulata has also been recorded.[5] A seventh putative hybrid withN. spathulata has been observed onMount Belirang in Jambi. Its lineage is unclear due to the apparent absence of other possible parent species in the area.[5]
