BOKORENSIS, A NEW SPECIES OF NEPENTHACEAE FROM CAMBODIA François Sockhom MEY 3 rue Frédéric Chopin, 59320 Haubourdin, France. Email: [email protected]

SUMMARY

A new species of Nepenthes L. (Nepenthaceae) from southern Cambodia, Nepenthes bokorensis Mey, is described and illustrated. The relationship between this new taxon and its putative relatives, N. kampotiana Lecomte, N. smilesii Hemsl. and N. thorelii Lecomte is also discussed.

Key words: Nepenthes, Cambodia, carnivorous , .

INTRODUCTION Cambodia, Laos, Thailand and . This geographic area has not received The geographical term Indochina is used thorough treatment in comparison to the to refer to the south-east Asian countries better known centres of Nepenthes located between India and China, diversity such as Borneo, Sumatra or, namely Burma, Singapore, Thailand, more recently, the Philippines (Clarke, Vietnam, Cambodia, Laos and Penin- 1997, 2001; Jebb & Cheek, 1997, 2001; sular Malaysia. The term is often Nerz & Wistuba, 1995; Robinson et al., confused with French Indochina, which 2009). In fact, the literature on Indo- was used, from 1887 onwards, to refer chinese Nepenthaceae is extremely poor to Vietnam (formerly the states of and almost no published research has Tonkin, Annam and Cochinchine), been carried out since the late 1890s and Cambodia and Laos (Brocheux & the early 1900s. Hemery, 2001). Thailand itself was The chronology of the Indochinese regarded as an independent and uncolo- species can be summed up as follows: nised buffer state between French Indo- William B. Hemsley described china (Cambodia, Laos and Vietnam) N. smilesii Hemsl. from a Thai specimen and British Indochina (Burma). in 1895; John M. Macfarlane described In this work, the term Indochina will N. anamensis Macfarlane based on a exclude Peninsular Malaysia and Singa- Vietnamese specimen in 1908; in pore, as that region is usually treated 1909 Paul Henri Lecomte named three with Borneo in the Nepenthes literature, taxa: N. geoffrayi Lecomte and N. and will focus on the countries of kampotiana Lecomte based on Camb-

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odian material, and N. thorelii Lecomte regions of Cambodia being one of the based on some collections from Viet- best-known examples. nam. Benedictus H. Danser synon- - Most of the type specimens are com- ymised N. smilesii with N. mirabilis prised of fragmented material, making it Druce in his revision of the genus difficult to study the species from that Nepenthes (Danser, 1928). area. Further, the location data for cer- Since these seminal works, in particu- tain specimens is incomplete or mislead- lar the studies of Lecomte, recorded in ing. For example, N. geoffrayi and Notulae Systematicae (Lecomte, 1909), N. kampotiana have been recorded from the Indochinese Nepenthes flora seems “Kampot, Cambodia”, but Kampot is to have been almost ignored, and the both the name of a southern province interest in Nepenthes raised by the work and the name of its principal city. of Danser (1928), Harms (1936), Kurata - Finally, the Indochinese species form a (1976), Jebb & Cheek (1997, 2001) and group of superficially similar species. Clarke (1997, 2001) inspired surpris- To the untrained eye, they all appear to ingly little interest in Indochinese share identical narrow with species. clasping bases and reddish lower In their ‘Skeletal revision of Nepen- pitchers. Their are also thes’, Mathew Jebb and similar, consisting of a with one- lectotypified the material of N. thorelii, flowered pedicels. Until recently, the and synonymised N. kampotiana and N. delimitations of these Indochinese geoffrayi with N. anamensis as the species were completely unknown and herbarium material of the two former most herbarium specimens from Indo- species are comprised of only frag- china were often incorrectly labelled as mented collections and detached inflo- “N. thorelii”, “N. aff. Thorelii”, “N. rescences (Jebb & Cheek, 1997). They anamensis” or were simply left undiag- also retained N. smilesii as a little known nosed. taxon, indicating that its inclusion with In his forthcoming work, Pitcher N. mirabilis would have been premature Plants of the Old World (2009), Stewart without further studies. McPherson will reinstate N. kampotiana The striking lack of study of the Indo- and synonymise N. anamensis with N. chinese Nepenthaceae can be explained smilesii following the interpretation pro- by at least three factors: vided to him by M. Cheek (pers. - The history of Indochina has involved comm.), an interpretation that is fully a great deal of internal and international supported by the author of this text (F. conflict, and the borders of countries Mey). such as Cambodia, Laos and Vietnam During a field trip to southern Cambo- have been opened relatively recently to dia in 2007, a new taxon was observed visitors and botanists. While tourists are on Phnom (Mount) Bokor (1080 m). now welcome and many areas of natural This plateau is located within the Preah wealth are managed for visitors, certain Monivong National Park (Bokor localities remain perilous, the landmined National Park), which is located near the

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town of Kampot, the main city of the slightly decurrent; longitudinal veins 3 eponymous province. The taxon on each side of the midrib in outer quar- possesses a combination of obvious, ter of the lamina, pinnate veins arising stable features that serve to distinguish it obliquely from midrib, midrib 2 mm from the other Indochinese species pre- wide; tendrils straight, terete, 9-18 cm sent in Cambodia, N. kampotiana, N. long, 2 mm in diameter; Leaves of the smilesii, and N. thorelii. This taxon from climbing stem as those of rosettes, but Bokor National Park is described as a tendrils coiling occasionally, 10-14 cm new species here. long, 2 mm in diameter. Lower pitchers 13-20 by 4-6 cm, ovate in the lower Nepenthes bokorensis Mey, spec. nov. third, narrowing above, often constricted – Figures. 1, 2A, 2B below the middle, and cylindrical or slightly infundibular towards pitcher Nepenthes thorelii Lecomte simile, mouth; two alae 14-15 mm wide run sed foliis longioris latioris oblongis ses- down ventral exterior surface from silibus vel subpetiolatis basaliter am- tendril to mouth, fringed with narrow plexicaulibus peristomio robusto cylin- filaments up to 10-12 mm long; pitcher drico pedicellis interdum 2-floribus dif- mouth oblique, peristome striate, loosely fert. cylindrical, to 20 mm wide and bulbous, - Typus: Marie Martin 1231 bis (holo ribs to 8 mm high, spaced to 1 mm P!), southern Cambodia, province of apart, occasionally raised to form a Kampot, Phnom Bokor, 800 m, triangular point; lid orbicular to broadly 7.xii.1968. elliptic, to 7 cm long by 6 cm wide, with a cordate base, often vaulted, lower Nepenthes bokorensis is most readily surface without appendages, crateriform distinguished from its near relatives by glands dense and numerous, to 0.5 mm its robust peristome, significantly across along midline, 0.2-0.3 mm broader leaves, the vaulted, orbicular lid elsewhere, glands sparse near margins; and its occasionally 2-flowered inflores- spur 11-12 mm long, simple but cences. occasionally bifurcated. Upper pitchers variable, generally to 25 cm by 6 cm, Terrestrial climber to 7 m tall. Stem of wholly infundibular, narrowly so rosette and short shoots cylindrical in towards base and greatly elongated in cross section, 7-9 mm diameter. Climb- lower third, occasionally swollen, form- ing stem terete to 1 cm diameter, inter- ing a faint hip above; alae reduced to nodes ca. 3 cm long. Leaves of the narrow ridges; pitcher mouth oblique; rosettes coriaceous, base attenuate and peristome striate, loosely cylindrical, to sessile, sometimes sub-petiolate, lamina 17 mm wide, outer margin often slightly oblong to linear-lanceolate, apex acute flared, ribs fine, to 0.4 mm high, spaced to obtuse, sometimes acuminate, 30-35 to 0.5 mm apart; lid orbicular or broadly by 7-8 cm, clasping the stem by three- elliptic, base cordate, to 6 cm long by 5 quarters of its circumference, rarely cm wide, often vaulted, margins

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Figure 1. Nepenthes bokorensis Mey. a. climbing stem with upper pitcher ; b. male ; c. detail of male inflorescence; d. fruit; e. seed; f. lower surface of pitcher lid; g. lower pitcher (all from photographs). Drawing by François Mey.

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frequently revolute, no appendages; spur brown hairs 0.5-1 mm long covering all as for lower pitchers. Male inflores- parts of , but sometimes greatly cence a raceme, to c. 100 cm, reduced leaving foliage almost glabrous. 60-70 cm long, rachis 20-30 cm long Colour of living specimens: leaves with c. 80 flowers borne solitary on green, stem, midrib and tendril yellow, pedicels to 5 mm long, but occasionally green, orange or red; pitcher exterior on 2-flowered partial peduncles, generally red, brown or purple, with androphore to 2 mm long; tepals faint purple blotching or, in upper orbicular to elliptic, 2 mm long. Female pitchers, yellow or pink; interior yellow- inflorescence a raceme, 60-100 cm, ish-green to creamy white, often rachis 7-20 cm with 30-80 flowers borne blotched purple; peristome red or purple, solitary on pedicels to 9 mm long, striped with darker bands of same or, in occasionally on 2-flowered partial upper pitchers, yellow to orange striped peduncles, ovary 4 mm tall; tepals red and purple; lid as for pitcher orbicular to elliptic, 4 mm long; fruit exterior; tepals brown or red. generally 10-25 mm long; seeds fusi- Specimens examined: form, ca. 50-100 per fruit, c. 7 mm long, Nepenthes bokorensis – M. Martin light brown. Indumentum of silver or 1231 bis (P!), female plant with flowers,

Figure 2A. Upper pitchers of Nepenthes Bokorensis 10

fruit and lower pitchers, Bokor Hill, 800 Lo-Thieu, Vietnam: lectotype. Thorel, m: holotype. Geoffray 324 (P!), upper 1032 (P!), Guia-Toan, Vietnam: syn- pitchers with leaves, Popokvil falls, type. Bokor Hill, 960 m. Geoffray 325, 328 Nepenthes sp. – Aug. Chevalier 36411 (P!), lower pitchers with leaves, Popok- (P!), Damrei Mountains, Kampot prov- vil falls, Bokor Hill, 960 m. Middleton ince, Cambodia. & Monyrak 539 (P!), two rosetted plants, Bokor Hill, 944 m. Vidal 4780 Distribution – Southern Cambodia, (P!), plant with upper pitchers, Bokor Phnom Bokor (Bokor Hill), from 800- Hill, altitude unknown. 1080 m altitude. Herbarium material Nepenthes geoffrayi – Geoffray 84, 85, (Aug. Chevalier 36411 (P!)) suggests 87, 88, 91, 92, 93 (P!), Kampot, Cambo- that N. bokorensis may be present at dia. other locations in the Damrei Mountains Nepenthes kampotiana – Geoffray 89, (Elephant Range), but further study is 90, 191, 362 (P!), Kampot, Cambodia. required to reveal the true extent of its Nepenthes smilesii – Charoenphol, distribution. Larsen & Warncke 4623 (P!), Phu Kradung, Loei, Thailand. Ecology – N. bokorensis occurs in Nepenthes thorelii – Thorel 1032 (P!), seasonally wet upland scrub and amidst

Figure 2B. Lower pitchers of Nepenthes bokorensis 11

sparse, stunted, lower montane forest. It (BKF) contain specimens mainly from grows mainly in open habitats exposed Bokor Hill (from photographs taken to strong or direct sunlight, readily from three herbarium specimens of producing a stem to 7 m long that Nepenthes collected at Bokor Hill scrambles and climbs through surround- deposited at BKF ([SN 093094, SN ing vegetation. Some plants may also 098240, third number is unreadable], grow in bright areas beneath trees, often identified as “N. thorelii”), it is obvious in damp soil covered by Sphagnum. that there are collections of N. Plants growing in full sun flower at an bokorensis in Bangkok, too. However, it earlier stage of development, frequently was not possible to detect the collector’s flowering when less than 60 cm tall. name on the herbarium label from the Populations of N. bokorensis on Bokor photograph alone). These have either Hill grow in sandy soil of pH 4.6 been misidentified as N. thorelii or (Turnble & Monyrak 589 (P!)) and ex- simply remained undiagnosed. The perience a severe dry season. In particu- N. bokorensis holotype (M. Martin 1231 larly exposed locations, N. bokorensis bis (P!)) was chosen from the Paris grows sympatrically with Drosera material. Additional Paris specimens, peltata Thunb., a well known species of such as August Chevalier 36411(P!), tuberous sundew, which exhibits some include Nepenthes taxa from different months of dry dormancy. It is not known locations in Cambodia that may fall whether N. bokorensis produces a within N. bokorensis. tuberous stem or thickened root system like its close relatives N. kampotiana, 2. Putative relatives. Nepenthes N. smilesii and N. thorelii but seedlings bokorensis is closely related to N. grown by the author from a seed kampotiana, N. smilesii and N. thorelii, collection on Bokor Hill demonstrate a but differs from all of these species in developing taproot very similar to those that the leaf is much broader and developed by the aforementioned also more oblong in shape. The occa- species. It seems likely that N. sional production of 2-flowered partial bokorensis also develops such storage peduncles is also unusual in this group organs, but additional field observations of species. It may also be distinguished are required to ascertain this. from N. kampotiana as the foliage of that species is typically glabrous, Etymology – The specific name refers whereas in N. bokorensis most parts of to Bokor Hill and Bokor National Park, mature plants are usually lined with from where this species was first short hairs. Nepenthes bokorensis may collected. be distinguished from N. smilesii by its pitcher morphology; the pitchers of Notes – N. smilesii are narrow, with a thin 1. Nepenthes bokorensis has been col- peristome, less colouration and shorter lected on a number of previous occa- tendril than those of N. bokorensis, sions. Herbaria in Paris (P) and Bangkok which are broad and have a character-

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istically robust peristome. Nepenthes populations of N. bokorensis, particu- bokorensis differs from N. thorelii by larly those on Bokor Hill, which has the attachment of the leaf to the stem; in recently been leased by the Cambodian N. bokorensis, the lamina is sessile to government for important private devel- sub–petiolate and clasps the stem, only opment. Therefore, the author considers ever becoming slightly decurrent, N. bokorensis to be potentially vulner- whereas in N. thorelii the lamina is able according to IUCN criteria (IUCN, nearly completely amplexicaul and 2004). The future of N. bokorensis in the strongly decurrent. Nepenthes bokor- Bokor National Park needs to be moni- ensis may also be distinguished from N. tored and the wider distribution of this thorelii by its pitcher morphology: the species across the highlands of south- lower pitchers of N. thorelii are ovate western Cambodia studied further. whereas those of N. bokorensis are ovate in the lower third and cylindrical 5. Pictures of habitat. Photos of N. above. Nepenthes bokorensis is unlikely bokorensis have been displayed on vari- to be confused with these three species ous online forums since august 2007, in the wild and it is not known to occur documenting the known forms of the sympatrically with any of them. There- taxon and its habitat. fore, no natural hybrids including -CPUK: http://tinyurl.com/bokorcpuk N. bokorensis as a parent species are -Pitcherplants.com: http://tinyurl.com/ known. bokorppc -FloraNepenthaceae: http://tinyurl.com/ 3. Carnivory. Cambodian Nepenthes, bokorfn including N. bokorensis, are generally called “ampuong sramoch” (“ants To read a detailed field report on pithole” in the Khmer language) by N. bokorensis by the author, visit the Cambodians from the province of website: Kampot and from the town of Pursat. http://www.nepenthesofthailand.com/ Indeed, observations indicate that bokor.htm ants seem to be the principle prey of N. bokorensis. On the herbarium label of ACKNOWLEDGEMENTS Middleton & Monyrak 589 (P!), the collectors noted that the fluid of the First and foremost, I thank my wife, pitchers has a pH of 2.7. Elisabeth, and my kids, Lucie-Ly, Alice and Ulysse for their never-ending 4. Conservation. In spite of wide- support throughout all the stages of this spread deforestation across much of work. Cambodia, the habitat of N. bokorensis It is no exaggeration to state that this in Bokor National Park has remained work never would have seen the light of relatively pristine. Unfortunately, the day if it were not for the unstinting expanding tourism industry in Cambodia support and encouragement of Andreas is now threatening the most accessible Fleischmann. Thank you for your

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advice, the corrections and the Latin nese Nepenthaceae literature. Thanks are diagnosis. also due to the Paris herbarium staff, and I am deeply grateful to Dr Alastair in particular to Dr Sovanmoly Hul, for Robinson for editing the text, for his allowing me to examine their collection selfless assistance and encouragement, of Nepenthes. and to Greg Bourke for trusting both me My last special thanks will go to my personally and my work. lone wolf friend: I could never have I would also like to specifically thank made it without you – Thank you very Tom Kahl for providing scarce Indochi- much.

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REFERENCES

Catalano, M. (2004-2008). http://www.nepenthesofthailand.com/

Clarke, C. M. (1998). “Nepenthes of Borneo”. Natural History Publications (Borneo), Kota Kinabalu. Xii + 207 pp. Reprinted 2007.

Clarke, C. M. (2001). “Nepenthes of Sumatra and Peninsular Malaysia”. Natural Publications (Borneo), Kota Kinabalu. X + 326 pp.

Danser, B. H. (1931). “The Nepenthaceae of the Netherlands Indies”, Bull. Jard. Bot. Buitenz. Ser. 3, 9 (3-4): 249 -438. Reprinted 2006 with an Introduction by Dr Charles Clarke by Natural History Publications (Borneo), Kota kinabalu. Vi + 206 pp.

Harms, H. A. (1936). “Nepenthaceae”, in: A. De Candolle, Prodromus systematis universalis regni vegetabilis, 17: 90-105.

Hemsley, W. B. (1895). “Nepenthes smilesii (Nepenthaceae)”, Kew Bulletin: 116. IUCN. 2001. IUCN Red List Categories and Criteria: Version 3.1 IUCN Species Survival Commission. IUCN, Gland, Switzerland and Cambridge, UK.

Jebb, M. & M. Cheek. (1997). “A skeletal revision of Nepenthes (Nepenthaceae)”, Blumea 42:1-106.

Jebb, M. & M. Cheek. (2001) “Nepenthaceae” Flora Malesiana, Series I, Volume 15: 1-157.

Kurata, S. (1976). “Nepenthes of Mount Kinabalu”. Sabah National Park Trustees, Kota Kinabalu, Sabah. 80 pp.

Lecomte, P. H. (1909). Notulae Systematicae: 59-65.

Macfarlane, J.M. (1908). “Nepenthaceae” In: A. Engler, Das Pflanzenreich: 39-40.

Robinson, A.S., A.S. Fleischmann, S.R. McPherson, V.B. Heinrich, E.P. Gironella & C.Q. Peña 2009. “A spectacular new species of Nepenthes L. (Nepenthaceae) pitcher plant from central Palawan, Philippines” Botanical Journal of the Linnean Society 159(2): 195–202.

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