A JOURNAL ON TAXONOMIC BOTANY, PLANT SOCIOLOGY AND ECOLOGY 12(2) REINWARDTIA A JOURNAL ON TAXONOMIC BOTANY, PLANT SOCIOLOGY AND ECOLOGY Vol. 12(2): 129-204.22 November 2004 Editors ELIZABETH A. WIDJAJA, MIEN A. RIFAI, SOEDARSONO RISWAN, JOHANIS P. MOGEA Correspondence and subscriptions of the journal should be addressed to HERBARIUM BOGORIENSE, BIDANG BOTANI, PUSAT PENELITIAN BIOLOGI - LIPI, BOGOR, INDONESIA REINWARDTIA Vol 12, Part 2, pp: 181 – 189 FOUR NEW SPECIES OF ARENGA (PALMAE) FROM INDONESIA JOHANIS P. MOGEA Herbarium Bogoriense, Bidang Botani, Puslit Biologi – LIPI, Bogor, Indonesia ABSTRACT MOGEA, JOHANIS P. 2004. Four new species of Arenga (Palmae) from Indonesia. Reinwardtia 12 (2): 181 – 189. ― Arenga distincta from Borneo and A. longipes, A. plicata, and A. talamauensis from Sumatra are described and illustrated for the first time. The descriptions are followed by information regarding the habitat and geographical distribution, and notes on morphological similarities with other, presumably related species. Leaves of A. longipes and A. talamauensis are paripinnate while the other two species are imparipinnate. Keywords: Arenga, Palmae, Indonesia ABSTRAK MOGEA, JOHANIS P. 2004. Empat jenis baru Arenga (Palmae) dari Indonesia. Reinwardtia 12 (2): 181 – 189. ― Arenga distincta dari Borneo; A. longipes, A. plicata, dan A. talamauensis dari Sumatra dipertelakan dan dilengkapi dengan gambar untuk yang pertama kali. Pertelaan tersebut disertai dengan keterangan mengenai habitat, persebaran geografi, dan kesamaan morfologi jenis-jenis yang diperkirakan kerabatnya. A. longipes dan A. talamauensis berdaun sirip genap, dua jenis yang lainnya berdaun sirip ganjil. Kata kunci: Arenga, Palmae, Indonesia INTRODUCTION The genus Arenga was based on the name given by Labillardière for a sugarpalm from Moluccas, which he named as Arenga sacchari- fera. The name can be found in Le Bulletin des Sciences par la Societé Philomatique 2 page 161 edited by de Candolle in 1800. The bulletin was published as proceedings of a series of talks given by Labillardière about his expedition in South East Asia in 1791 – 1792. Actually the sugarpalm had been already been described previously by Rumphius in 1741 in the Herbarium Amboinense 1 page 57 and Figure 13. At that time it was cited as ‘Palma indica vineria secunda’, meaning second wine-producing palm of the Indies. The first wine-producing palm known to him at that time was probably the coconut-palm. Rumphius described the sugarpalm mostly in comparison with other well known flora, fauna, and in relation to the daily lives of the people of Ambon. He also mentioned local names of the palm, namely gomutus, gamut, and areng. The last one apparently was latinized by Labillardière for the name of the genus. However, the sugarpalm was not mentioned in the Species Plantarum of Linneaus (1753), though eight other economic palms were cited namely Areca catechu, Borassus flabellifer, Calamus rotang, Caryota urens, Cocos nucifera, Corypha thebaica, Corypha umbraculi-fera, and Elate sylvestris (Moore & Dransfield, 1979). Other species of Arenga were published firstly by Martius (1838) in Historia Naturalis Palmarum (Arenga obtusifolia and A. porphyrocarpa, the latter at that time named as Orania porphyrocarpa). During 1844 – 1845, Griffith published three other species of Arenga in the Calcutta Journal of Natural History Volume 5 No. 17, 19, and 20. Later in 1850, he published again the same species in The Palms of British East India. The species were A. westerhoutii, A. wightii, and A. nana (at that time named as Wallichia nana). In 1875, Blake described Saguerus australasicus (= A. australasica) from Queensland Australia. In 1878, Wendland & Drude published a list of palms, and under Arenga, eight species were listed. namely A. bonnetii, A. griffithii, A. javanica, A. manillensis, A. obtusifolia, A. saccharifera, A. westerhoutii and A. wightii. In 1886, Beccari described A. brevipes and A. undulatifolia, both from Borneo, and A. engleri from Taiwan. In 1889, he published A. microcarpa from Papua New Guinea, in 1891 A. listeri from Christmas Island in the Indian Ocean. In 1898 Bailey described A. gracilicaulis from Papua New Guinea, and in 1907 Beccari again described A. ambong from Mindanao, the Philippines; in 1909 he removed Caryota tremula of the Philippines to A. tremula. In 1965, Moore & Meijer added one species from Sabah, namely A. retroflorescens. Finally, in 181 182 REINWARDTIA [VOL.12 1971, Hatusima changed A. engleri to A. tremula var. engleri In 1988, Wei described A. micrantha from China, and finally in 1989 she also described A. longicarpa from Guangdong South China. A genus very similar to Arenga is Didy- mosperma. It was described by Wendland & Drude in 1883; however, the list of six species of the genus had been published previously in 1878 in the Index General des Palmiers edited by Kerchove de Denterghem. The species in the list were D. caudatum, D. horsfieldii, D. reinwardtii, D. nanum, D. porphyrocarpum and D. tremulum. The last three were transferred from Arenga. In 1889, Beccari described D. hastatum and D. hookerianum, both from the Malay Peninsula, and D. borneense from Borneo. In 1892 J.D. Hooker described D. gracile from Assam; Beccari in 1910 added two varieties of D. caudatum, namely var. stenophylla and var. tonkinense, both from North Vietnam. In 1937, Gagnepain elevated the last variety to species rank as D. tonkinense. In 1960, Moore studied the related genera Arenga, Didymosperma, Wallichia, and Caryota. He put all these genera under the subfamily Caryotoideae, and included Didymosperma under sinonymy with Arenga, placing it under section Didymosperma. He also removed D. porphyro- carpum, D. caudatum, and D. nana to Arenga. His view was followed by Whitmore (1970) who transferred D. hastatum and D. hookerianum, and Dransfield (1980) who transferred D. borneense to Arenga. Hence, in total the genus consisted of 25 species and two varieties. Although the genus has a long history, some of the species remain poorly known and poorly circumscribed, leading to difficulties in identification. For example A. pinnata, A. westerhoutii and A. wightii, are all large palms with solitary habit that are superficially similar and easily confused; in some areas such as in south of Thailand and Malay Peninsula,A. pinnata and A. westerhoutii co-occur in the same locality and habitat. The Philippine species A. tremula, A. mindorensis, A. engleri and A. undulatifolia have also been confused and there is a great complexity of variation in A. caudata in Indochina, Thailand and the Malay Peninsula needing clarification. One reason for these problems may be because the genus has not been studied in detail since the work of Moore in 1960. Therefore a revision of the genus is timely, especially as many more collections have been made and are particularly rich in the herbaria at Leiden, Kew and Bogor. During the revision, four new species were identified. They are described in this paper. The revision of the genus will be presented separately. In the specimen citation, “!” means that the specimen had been examined by the author, s.fl. means staminate flower, and p.fl. means pistillate flower. 1. Arenga distincta Mogea, sp. nov. –– Fig. 1 and 2 Frutices monoeci pleonanthi caulibus ad 2 m altis, ca 1.5 cm diam. (vaginis incl.), internodiis 4 – 8 cm longis. Folia imparipinnata, ca 1 m longa (vaginis, petiolis, foliolisque incl.); ligula 4 – 6 cm longa; foliola alterna, ca 3 in utroque latere, petiolulis ad 0.8 cm longis, lateribus trullatis, subpanduratis, 14–- 24 cm longis, 6 – 9.5 cm latis, margine distali praemorsea, foliolo terminali simplice, elliptico, ca 20 cm longo, 10 – 12 cm late; costae 6 – 10, quarum tres ad centrum prominensimus, ceteris characteribus similaris Arenga hastata (Beccari) Whitmore, praeter margine sepala crenata cum 4 – 6 lobis parvis. TYPUS: Borneo, South Kalimantan, District Tapin, Muara Uya, alt. 100 m, fl. (bud).10.Nov.1971, Dransfield & Saerudin 2801 (BO - holo!, BH, L!). Monoecious, pleonanthic shrub, forming clusters; stem up to 2 m long, 1.5 cm diam. (including leafsheath), internodes 4 – 8 cm long. Leaves 5 – 9 in crown, imparipinnate; leafsheath 10 – 20 (–30) cm long, margin and ligule united forming a fine soft black mat; ligule 4 – 6 cm long; petiole 20 – 30 (– 60) cm long, 0.3 cm diam.; blade 45 cm long, 30 cm wide, inter and ultrajugal part 5 – 10 cm long, upper surface of the leaflets glabrous, lower surface with brown indumentum; number of lateral leaflets on either side (2 –) 3 (– 5), in one plane, alternate; main longitudinal veins one, petiole up to 0.8 cm long; lateral leaflets trullate, rather pandurate, 14 – 24 cm long, 6 – 9.5 cm wide, top margin praemorse; terminal leaflet obtriangular, ca 20 cm long, 10 – 12 cm wide; main longitudinal veins 6 – 10, either 2 or 3 of the main longitudinal veins more prominent, distal part of the terminal leaflets with 3 lobes, each lobe with acumen, the middle lobe the longest, up to 3 cm long. Staminate inflorescence sometimes arising from a cleft between the leafsheaths, solitary, slender, up to ca. 45 cm long; peduncle ca 2 cm long, number of bracts ca. 4, erect, slender, up to 10 cm long; peduncle covered by the bracts, up to 20 – 30 cm long; each bearing one rachilla; rachilla pendulous, slender, 20 – 25 cm long. Staminate flower ellipsoid, 8 mm long, 3.5 mm diam.; sepal broadly ovate ca. 2 mm long, 3 mm wide, margin 2004] MOGEA: Four new species of Arenga from Indonesia 183 crenulate, lobes 4 – 6; petal ellipse, up to 8 mm long, 3.5 mm wide; stamens 20 – 30, filament ca. 0.5 m long, anthers ca. 4 mm long; pistillode absent. Pistillate inflorescence similar to the staminate one, mostly shorter, 20 – 30 cm long. Pistillate flower globose, ca. 4 mm diam.; sepal broadly ovate 1 mm long, 2 mm wide, margin crenulate with 4 – 6 small lobes; petal ovate, ca. 4 mm long, 3 mm wide; ovary globose, ca. 4 mm diam.; stigma inconspicuous. Fruit globose, ca. 10 mm diam. Seed one, subglobose to ellipsoid, ca. 6 mm long, surface often with brown spots. Seedling with bifid eophyll, leafsheath 2 cm long, petiole 1 cm long; blade obovate, ca. 4 cm long, 2 cm wide, top margin praemorse, lower surface whitish, rather rough. Fig.1. Arenga distincta. A. habit of plant cultivated in Bogor Botanic Garden XI.B.XIII.187, other stems of the cluster removed; B. a portion of the rachilla; C. staminate flower nearly at anthesis; D. longitudinal section of the staminate flower; E. calyx of the staminate flower after the corolla and stamens have been removed; F. pistillate flower, a black spot near the flower (indicated by an arrow) is the scar of the protandrous staminate flower; G. pistillate flower after one of the petals has been removed; H. a part of infructescence; I . fruit as seen from the side; J. seed as seen from the base; K. seed as seen from the side; L. longitudinal section of the seed showing the homogenous endosperm and lateral embryo. B – G after Mogea 5810; I – L after Mogea s.n. HABITAT AND GEOGRAPHICAL DIS- TRIBUTION. Endemic to Borneo: Sabah, Sarawak, East and South Kalimantan in lowland mixed dipterocarp forest, up to alt. 500 m. However, usually in small populations. VERNACULAR NAMES. Sabah: sasa utan (Murut language), anudur (Melayu languge), kabal pisakwau (Orang Sungai language). NOTES. The specimen Dransfield 5306 from Sarawak has 5 leaflets on either side of the rachis. According to the field notes: upper surface of the leaflets deep green, lower surface brownish. Sepals green, petals pale green, ripe fruit bright red, mesocarp white. Another collection, Dransfield & Saerudin 2801 (type specimen) from South Kalimantan, has a vegetative bud arising at the node 30 cm from the base of the stem. The surface of the seeds from East and South Kalimantan are covered with faint brown spots. Whether the seeds from Sabah and Sarawak have the same surfaces is not known. The lateral leaflets of the specimen Mogea et al. B-1559 and Mogea et al. B-1593 from East Kalimantan are rather more similar to Arenga hastata than to A. distincta. The similarities are in the length of the petiole, the form of the leaflets, the shiny glabrous lower surface and the texture. It is possible that this represents a natural hybrid between the two species, as A. hastata also occurs in Sarawak and Central Kalimantan. SPECIMEN EXAMINED. BORNEO. Sabah: District Ranau, southeast of River Mongkodoit, p.fl .(young) 11.Apr. 1983, SAN 96539 Joseph et al. (K!, L!, SAN); District Labuk, Sugut, Sinurai Village, s.fl.16.Apr.1983, SAN 95380 Aban & Dewol (A, K!, L!, SAN, SAR!); District Telupid, ca Mile 8, Ente Lebun - Menanam, alt. 150 m, s.fl.24.Oct.1979, Dransfield 5801 (K!, SAN); District Lahad Datu, Ulu Sungai Danum, s.fl.1.Sep.1976, SAN 85240 Stone (K!, SAN); District Tongod, Ulu Menanam Village, alt. 500 m, s.fl.2.Oct.1978, SAN 89298 Dewol & Kodoh (K!, SAN); District Betotan, alt. 25 m, fr.16.May.1933, Castro 3247 (K!); District Beluran, south of Labuk bridge, alt. 400 m, fr.8.Dec.1979, SAN 91070 Dewol (K!, SAN, SAR!). Sarawak : 2nd Div., foot path to Mt. Silantek, left up stream of river Silantek, Mile 85, Sri Aman, alt. 180 m, fl.(in bud).21.Aug.1980, SAN 424575 Paie (K!, KEP, NY, SAN); Ulu Belaga, Kuala Linau, River Masoh, Rumah Nyaving, alt. 200 m, s.fl.10.Aug.1975, Dransfield et al. 4700 (BM!, K!, KEP, L!, SAR!); 4th Div., Mulu National Park, foot Mt. Muda, alt. 150 m, sterile, 12.Oct.1977, Dransfield 5306 (K!, SAN); Niah National Park, near river Sekaloh, s.fl.+ p.fl. 28.Mar.1979, SAN 40054 Chai et 184 REINWARDTIA [VOL.12 al. (K!, NY, SAN); Betotan, logged area, Timber Concession, alt. 25 m, p.fl. 22 Apr.1933, Orolfo 3079 (K!, SAR!). East Kalimantan : District Bulungan, Ulu Sebuku, s.fl.+ fr., Aug. 1912, Amdjah 390 (BO!); s.fl. + p.fl. 8.Sep. 1912, Amdjah 552 (BO!); District Kutai, Long Hut, s.fl. 19.Aug.1925, Endert 2662 (BO!, L!); Nature Reserve Mantoko, river Sengata, alt. 40 m, s.fl.+ p.fl.+ fr. 15.Jun. 1971, Dransfield 1578 (BO!, L!); northwest Tabang, foot of Mt. Batu Kenye, along Belayan river, alt. 100 – 150 m, s.fl.10.Jan.1979, Mogea et al. B-1593 (BO!, KYO!); ibid., fl.(in bud), 10.Jan.1979, Mogea et al. B-1594 (BO!, KYO!); around Jelini, fr.6.Jan.1979, Mogea et al. 1559 (BO!, KYO!), sterile, 6.Jan.1979, Mogea et al. B-1560 (BO!, KYO!); G. Mendam, s.fl.16.Jan.1979, Murata et al. B-2384 (BO!, KYO!). South Kalimantan: Mts. Meratus, Barabai, Kiu, foot of Mt. Besar, mixed lowland dipterocarp forest, on a river bank, alt. 200 m, s.fl.14.Nov.1971, Dransfield & Saerudin 2801 (BO - holotype!, BH, L!). CULTIVATED IN BOTANIC GARDEN. Bogor: living collection under registration number: XI.B.XIII.187 and 201 originally from seed of the collection of Dransfield & Saerudin 2801; ibid., s.fl.24.Aug.1984 Mogea 5810 (BO!); ibid., fr.4.Aug.1986., Mogea 5854 (BO!). Fig. 2. Arenga distincta. A. a portion of the top of the plant bearing leaf and staminate inflorescence; B. a portion of peduncle showing conspicuous villose hairs covereing the bracts; C. a portion of inflorescence showing triads; D. seedling. A after Mogea 5810, B – C after Mogea 5854, D after Mogea s.n. 2. Arenga longipes Mogea, sp. nov. --- Fig. 3 and 4. Fructices basipetalo-hapaxanthi, monoecicespi- tosi vel cum stolonibus subterraneis, . Caulis pars basalis cum ca. 4 internodiis; internodiis ca.. 3 cm longis, ca. 5 cm diam.; internodiis superis ad 2.5 m longis, ca. 1 cm diam., pedunculoideis. Folia paripinnata, foliolis alternis, ca. 16 in utroque latere; lateralibus lineariis, glabris. Inflorescentia solitaria vel ramificans, mascula axillaris, saepe ramificans, rachillae 2 – 6, graciles, pendulae, ad 30 cm longae, saepe ramificantes; floribus masculis gemminatis, ellipticis, ca 1 mm longis, 3 mm diam., sepalis, distinctis imbricatis, staminibus ca 10. Inflorescentia femina similis, sed bisexualis, rachillae inramificantes, ad apex caulis, floribus in triadibus ferentibus; flores pistillati elliptici, ca 7 mm longi, 3 mm diam., sepalis 3 distinctis, imbricatis, staminodiis 3, ovario biloculare, utroque loculo unico ovulo; stigmatibus sessilibus, bilobatis. TYPUS: Sumatra, Prov. Bengkulu, District Rejang Lebong, beside the main road on Km 18 from Kapahiang to Bengkulu, on the slope of mixed dipterocarp forest, altitude 700 m, s.fl.25.Aug.1973, Dransfield 3585 (BO! - holo, L!). Shrub, clustered, hapaxanthic, monoecious or dioecious; distances between the base of stems ca. 50 cm, stem connected by underground stolons; stolon terete, ca. 0.5 cm diam. Proximal stem terete, 25 cm long, 5 cm diam; internodes ca. 3 cm, surface glabrous; the top internode forming the peduncle, terete up to 250 cm long, 1 cm diam., rather tomentose and vilose up to massive woolly leafsheath. Leaves 5 in crown, paripinnate, at maturity subsequent leaves gradually reduced in size. Leafsheath up to 40 cm long, mouth of the leafsheath united with ligule forming a fine mat; ligule up to 10 cm long; petiole terete, 50 – 250 cm long, 1 – 1.5 cm diam.; blade 100 cm long, 60 cm wide; rachis glabrous; interjugal part 2 – 7 cm, pulvinus 0.5 cm long; petiole absent. Lateral leaflets ca. 16 on either side, ± in one plane, subalternate, both surfaces glabrous. Lateral leaflets linear, 30 – 60 cm long, 3 – 4.5 cm wide, at the base cuneate, upper margin praemorse, the tip rather obtuse to acute, praemorse; main longitudinal vein of the lateral leaflets one, other lateral veins arising from the base of the leaflet diverging longitudinally. Terminal leaflet obtriangular, 15 – 25 cm long, 3.5 – 6 cm wide, at the base cuneate, at the margin praemorse, at the top with 2 or 3 triangular lobes, margin praemorse obtuse to acute, main longitudinal veins two or three; two top leaves tube-like resembling the prophyll and bract of the inflorescence, terete, 85 cm long, ca. 1 cm diam. Inflorescence solitary, in one stem 2004] MOGEA: Four new species of Arenga from Indonesia 185 bearing 1 to 3 inflorescences, erect; in the dioecious plant, the staminate inflorescence at the top of the stem, in monoecious plant the staminate inflorescences below the pistillate ones. Peduncle slender, terete, up to 30 cm long, 0.3 cm diam; prophyll tube-like, 3 – 15 cm long; bracts 3, tube-like, 10 – 30 cm long, 0.3 – 1.5 cm diam., surface glabrous; number of rachilla 2 – 6, pendulous, slender, up to 30 cm long, sometimes branched. Staminate flower ellipsoid, sepals broadly ovate, 1.5 – 2 mm long, surface minutely roughened, petal elliptic, ca. 10 mm long, 3 mm wide, surface striate; stamens ca. 10, filament ca. 0.5 mm long, anther 5 – 7 mm long, pistillode absent. Pistillate inflorescence similar to the staminate one, at the top of the stem; number rachillae 3 or 4, never branched. Pistillate flower ellipsoid, ca. 7 mm long, 3 mm diam., sepal obovate , ca. 1.5 mm long, 3 mm wide; petal elliptic, ca. 7 mm long, 4 mm wide; staminodes 3, ca. 1.5 mm long, each inserted between the joined petasl; ovary globose, ca. 4 mm diam., 2 cells, each with one ovule; stigma sessile, 2 lobed, lobes ca 1.5 mm long. Fruit not known. Fig. 3. Arenga longipes. A. habit of two plants, one of them bearing the inflorescence (the drawing based on the photograph made by Dr. J. Dransfield), B. top of the stem bearing the staminate inflorescence. After Dransfield 3585 (BO – type specimen). HABITAT AND GEOGRAPHICAL DISTRI- BUTION. Endemic to Sumatra, Prov. Bengkulu in disturbed mixed dipterocarp forest, alt. 600 – 700 m. In a small population very close to the main road between Kapahiang – Bengkulu at Km 19 – 20. However, it was not found in the nearest one hectare of Tabah Pananjung Nature Reserved which is located near the population. According to Dr. J. Dransfield in his field notes, at anthesis the flower smelled of oil of wintergreen (Gaultheria sp.). Fig. 4. Arenga longipes. A. portion of the leafsheath, B. the middle of the leaf, C. longitudinal section of the staminate flower, D. calyx of the flower after the corolla and stamens have been removed, E. pistillate flower, one of the petals has been removed. A – D after Dransfield 3585 and E after Dransfield 3647 all from BO. NOTES. There are six clusters of A. longipes (Mogea 5965) growing side by side with a population of A. porphyrocarpa (Mogea 5964) and Caryota mitis. These same natural habitat, distribution, and their morphological similarities could suggest that longipes is an intermediate form between these two genera. The stoloniferous habit is very rare in Arenga being otherwise known only in A. retroflorescens and A. obtusifolia. It is curious that all the paripinnate Arenga spp such as A. longipes, A. talamauensis and A. hastata have leaflets glabrous on both surfaces 186 REINWARDTIA [VOL.12 whilst in the other species of the genus which are imparipinnate, the leaflets are glabrous on the upper surface. The lower surface is always covered by wax and white or brown tomentum, except in A. caudata. In this last species, the lower surface of the leaflet has very sparse indumentum or is glabrous. The glabrous surfaces of the both sides of the leaflet is one characteristic typical of Caryota. However, the bipinnate leaf, the always solitary inflorescence, and a ruminate endosperm are characters which are absent in A. longipes (except for the ruminate endosperm of A. longipes which was so far not available). The similarities between A. longipes and A. porphyrocarpa are particularly in the similar size, number of the lateral leaflets, number of the rachilla, number of stamens and form and number of staminodium. A. longipes is very easily identified from other species of Arenga because the leaf is paripinnate, both leaflet surfaces are glabrous, the top of the stem is slender, elongate and similar to the peduncle, sometimes the staminate rachillae branch and the pistillate flower has a staminodium. The only other species that has a staminodium is A. porphyrocarpa. The branched staminate rachilla as shown in Fig. 3B in fact is an unusual form as it was the only one collection found among the other five collections examined. SPECIMEN EXAMINED. SUMATRA. Prov. Bengkulu, District Rejang Lebong, Km 18 from Kapahiang to Bengkulu, on slope of disturbed dipterocarp forest near a private coffee estate, alt. 700 m, s.fl.30.Oct.1987, Mogea 5965 (BO!,K!, L!); ibid., Km 20, alt. 500 m, s.fl.26.Aug.1973, Dransfield 3604 (BO!); ibid., s.fl.26.Aug.1973, Dransfield 3605 (BO!); ibid., Km 22, alt. 600 m, s.fl.+p.fl.29.Aug.1973, Dransfield 3647 (BO!). 3. Arenga plicata Mogea, sp. nov. – Fig. 5 Frutex caulis ad 1.5 m altis, ca 3 cm daim. (vaginis incl.), pleonanthus, dioeca. Folia impari- pinnata, ca 3.2 m longa (vaginis, petiolis, foliolis incl.), foliolis alternis, ca 12 in utroque latere, lateralibus obtrullatis 28 – 39 cm longis, 3.5 – 10.5 cm latis, basi cuneatis plicatis sursum gradatim applanatis, margine distali praemorsa, apice acuto vel truncato, infra cinnamomeis, costa principali 1. Inflorescentia staminata A. retroflorescenti affinis, pedunculo crasso, bracteis dense imbricatis laceratis rachillam totam includentibus, rachilla 1 compacta ellipsoidea 4 – 6 cm longa, 3 cm diam., floribus ca 60 dense fasciculatis nodis obscuris obvoideis ca 8 mm longis, staminibus 33 – 38. TYPUS : Sumatra, Prov. Jambi, District Kerinci, road from Penetai to Sungei Penuh, lowland mixed dipterocarp forest, alt. ca 300 m, s.fl.21.Jul.1972, Dransfield 2606 (BO-holo!, BH, K!, L!). Fig. 5. Arenga plicata. A. terminal leaflet, B. lateral leaflets of the middle leaf, C. lateral leaflets of the base of the leaf, D. a portion of the stem bearing the staminate inflorescence, E. staminate flower at anthesis, F. longitudinal section of the staminate flower, G. stamen. A – G after Dransfield 2606 (BO – type specimen). Pleonanthic, dioecious shrub; stem up to 1.5 m long, ca 3 cm diam., internodes 3 – 5 cm long, nodes conspicuous. Leaves imparipinnate, leafsheath ca. 20 cm long, outer surface rough, margin and the ligule forming a fine brown mat, ligule fibrous, many fibers stout and strong, up to 20 cm long; petiole terete, up to 125 cm long, ca. 1 cm diam., surfaces rough, brown. Blade 175 cm long, 40 cm wide; lateral leaflet ca. 12on either side, alternate, at the base of the blade 4 leaflets in groups, fan-like, upright, other leaflets ± in one plane, inter and ultrajugal part 3.5 – 10.5 cm long, ultrajugal mostly 3.5 cm long; pulvinus up to 0.5 cm long. Lateral leaflets trullate, 28 – 40 cm long, 3.5 – 10.5 cm wide; plicate at the cuneate base gradually flattening through to the tip; apex acute to truncate, margin praemorse; abaxial surface reddish tinged; main longitudinal vein 1, quadrangular in cross section, 2 mm long, 1 mm 2004] MOGEA: Four new species of Arenga from Indonesia 187 wide. Terminal leaflet obtriangular, 34 – 37 cm long, 14 – 19 cm wide, at the apex with 4 or 5 lobes; lobes acute; main longitudinal veins ca. 6. Staminate inflorescence solitary, infrafoliolar, peduncle covered by bracts, terete, 2 cm long, 0.3 cm diam., bracts ca. 4 obscuring the spike; rachilla 1, ellipsoid, 4 – 6 cm long, 3 cm diam., congested with flowers; bracteolule absent; number of flowers in the rachilla ca. 60; flower arrangement in the rachilla obscure; staminate flower obovoid, ca. 8 mm long, 2.5 mm diam.; sepal obovate, ca. 2. mm long, 2.5 mm wide; petal lanceolate, ca. 8 mm long, 2 – 3 mm wide, outer surface striate; stamens 33 – 38, filament ca 2.5 – 4 mm; stigma ca. 2.5 mm; pistillode absent. Pistillate inflorescence and fruit unknown. NOTES. The plant is similar to A. retroflorescens particularly in its pleonanhtic habit, dioecy, nodes of stem very conspicuous, and erect spicate staminate inflorescence, and congested flower arrangement. The plant is known only from the type collection. 4. Arenga talamauensis Mogea, sp. nov.– Fig. 6 Frutices dioeci basipetalo-hapaxanthi caulibus 2 m altis, caulis apicalis pedunculo similis ca. 20 cm, ca. 0.2 cm diam. Folia paripinnata, in nodis caulis apicalibus bracteiformibus. Foliolis alternis, ca. 4 in utroque latere, lateralibus trullatis, + panduratis, 16 – 18 cm longis, 3.5 – 10.5 cm latis, basin cuneatis, margine distali praemorsa. Inflorescentia staminata in caule apicali 2 fasciculi, curva, 15 – 35 cm longa. Rachillae ad tertius axem ramificantes, ca. 5, exiles, 12 – 20 cm longae, unisexuales. Flores staminati elliptici, 6 – 7 mm longi, 3 – 4 mm lati, sepalis petalisque glabrescentibus, staminibus ca. 25, pistillodio carenti. Flores pistillati elliptii, ca. 4 mm longi, 3 mm lati, staminodiis carentibus, ovario globoso. TYPUS: Sumatra, Prov. West Sumatra, District Pasaman, Lubuk Sikaping, Bukit Kabung, primary dipterocarp forest, alt. 800 - 1000 m, s.fl. (young).22.Jun.1907, Bünnemeijer 1216 (BO! - holo). Shrub, apparently in clusters, hapaxanthic, dioecious, stem forming the peduncle at its tip, slender, terete ca. 20 cm long, 0.2 cm diam. Leaves paripinnate, the terminal leaf reduced forming a bract; leafsheath 20 cm long, at the mouth with the ligule forming a fine mat; the ligule up to 1 cm long; peduncle slender, terete, (3–)12 – 16 cm long, 0.3 cm diam.; blade 37 – 50 cm long, 26 – 34 cm wide; pulvinus 0.5 cm, interjugal part 3 – 8 cm, ultrajugal part ca. 12 cm, petiolule up to 1 cm long; lateral leaflets 4 on either side, alternate, + in one plane, trullate, 16 – 18 cm long, 6 – 8 cm wide, at the base cuneate, at the tip + with acumen, top part of the leaflet margin praemorse, main longitudinal vein 1; terminal leaflet obtriangular, asymetric, 12 – 14 cm long, 3.5 – 7 cm wide, obtuse at the tip, main longitudinal veins 2 or 3, top part of the leaflet . Fig. 6. Arenga talamauensis . A. top of the stem showing hapaxanthic habit, B. a portion of the rachilla showing a triad, C. a portion of staminate rachilla showing only one developed staminate flower from each of the triads, D. staminate flower at anthesis, E. calyx of the staminate flower after the corolla has been removed, F. pistillate flower. A – B: after Bünnemeijer 1216 (BO – type specimen); C – F: after Bünnemeijer 473 (BO). margin praemorse. Staminate inflorescence multiple, consisting of 2 inflorescences at the top of the stem, curved, 15 – 35 cm long, branching to the second order; the prophyll tube-like, ca. 2 cm long; bracts 4, tattered, the young bract tube- like, 12 – 15 cm long. Rachillae, ca. 5, slender, 12 – 20 cm long, unisexual; staminate flower in pairs, only either one developing to mature flower; staminate flower ellipsoid, 6 – 7 mm long 3 – 4 mm diam.; sepal ovate, 1.5 – 2 mm long, surfaces glabrous; petal elliptic, ca. 6 – 7 mm long, surfaces striate; stamens ca. 25, filaments 0.5 mm long, anther ca 3 mm long, pistillode absent. Pistillate inflorescence similar to the 188 REINWARDTIA [VOL.12 staminate, at the 3 or 4lower nodes number. Pistillate flower ellipsoid, ca 4 mm long, 3 mm diam., sepal ovate ca. 3 mm long, 2.5 mm wide; petal elliptic, ca. 6 mm long, 2 mm wide, staminodium absent; ovary globose, ca. 2.5 mm diam.; stigmas sessile, 2-lobed, ca. 0.8 mm long. Fruit unknown. HABITAT AND GEOGRAPHICAL DISTRI- BUTION. Endemic to Sumatra, Prov. West Sumatra, Lubuk Sikaping, Bukit Kabung and Mt. Talamau, in primary dipterocarp forest, alt. 800 – 1000 m, very rare, the population might be very little. NOTES. The paripinnate leaves in Arenga so far are known in A. talamauensis, A. hastata and A. longipes. In the section Didymosperma, multiple inflorescences with the inflorescence consisting of more than one rachilla are present in Arenga talamauensis and A. porphyrocarpa. Other species such as A. nana, A. caudata, A. longipes, and A. gracilis have a solitary inflorescence but each inflorescence may bear more than one rachilla. Other species in the section have a solitary inflorescence, which bears only one rachilla such as in A. caudata var. tonkinensis, A. distincta, A. hastata, and A. plicata. SPECIMEN EXAMINED. SUMATRA. Prov. West Sumatra, District Pasaman, Lubuk Sikaping, northwest of “Lelling”, Ophir, Mt. Talamau, primary mountain dipterocarp forest, alt. 1000 m, p.fl. Apr.1907, Bünnemeijer 473 (BO!). ACKNOWLEDGEMENTS I would like to express my sincere thanks to Mr. J. Teller an officer from the Ministry of Foreign Affair and the Ministry of Education and Culture of the Government of the Netherlands who made available to me a four months grant (from October 1986 to January 1987, and April 1987) to study in the Rijksherbarium Leiden. I am also very grateful to Dr. M.M.J van Balgooy for his continuous help in obtaining the grant for me through the Cultural Agreement of the Netherlands Embassy in Jakarta. I am also indebted to Mr. L. Mole who assisted me to obtain a two months grant (from February to March 1987) from the Royal Society of London that enabled me to study the important collection and the literature in the Royal Botanic Gardens Kew as well as in the British Museum of Natural History. For the use of facilities I am grateful to the keepers of the Herbaria of BM, K, L, BO and SAR. Dr. J.F. Veldkamp helped me in preparing the Latin diagnoses of Arenga talamauensis and A. plicata. I am very much indebted as well to Dr. J. Dransfield for discussion and suggestions during my study of the genus. I am very much appreciated to Mr. Iskak Syamsudin from the Herbarium Bogoriense who provided all the line drawing. REFERENCES BAILEY.F.M. 1898. Contribution on the Flora of the (British) New Guinea. Queensland Agric. Journal 3: 203. BECCARI, O. 1886 ─ 1889. Nuove Palmae Asiatiche. Malesia 3 :169 – 200. BECCARI, O. 1989. Arenga microcarpa in K. Schumann. Die flora von Kaiser Wilhelmsland. : 16. BECCARI, O. 1891. Arenga listeri from Christmas Island. In OLIVER (Editor). Hooker’s Icon. Plantarum 3 :10. BECCARI, O. 1907. Palms of the Philippines. Philippine Journal of Science 2 :219 – 240. BECCARI, O. 1909. Palms of the Philippines. Philippine Journal of Science 4 : 601 – 637. BECCARI, O. 1910. Indo Chinese Palms. Webbia 3: 206 – 208. BECCARI, O & HOOKER, J.D. 1892. in HOOKER, J.D. Flora of the British India 6: 420. DRANSFIELD, J.1980. Systematic Notes on Some Bornean Palmae. In JEREMY, A.C. (Editor). Notulae et Novitates Muluensis. Botanical Journal of Linnean Society 81:1 – 46. GAGNEPAIN, F.1937. Didymosperma tonkinense. In HUMBERT (Editor). Flora Gěn. Indochine 6: 966. GRIFFITH, W.1845. The Palms of British East India. Calcutta J. Nat. History 5: 445 - 491. GRIFFITH, W. 1850. The Palms of British East India. Charles A. Serrao, Calcutta. HATUSIMA., S. 1971. Flora of Ryukyu Island :754. Japan. LABILLARDIERE, H. 1800. in CANDOLLE, A. P., Le Bulletin des Sciences, par la Sociĕtĕ Philomatique 2: 161. LINNEAUS, C. 1753. Species Plantarum. 2 Volumes. Stockholm. MARTIUS, K.F.P. von. 1823 – 1850. Historia Naturalis Palmarum. 3 Vols. Munich. 1st and 2nd Edition. MOORE, H.E. Jr. 1960. A New Subfamily of Palms – the Caryotoideae. Principes 4 (3): 102 117. MOORE, H.E. Jr. 1963. Arenga australasica. Gentes Herbarium 9: 268. MOORE, H.E. Jr. & J. DRANSFIELD. 1979. Typification of Linnean Palms. Taxon 28: 59 – 70. MOORE, H.E. Jr. & MEIJER, W. 1965. A New Species of Arenga from Borneo. Principes 9: 100 – 103. RUMPHIUS, G.E. 1741. Herbarium Amboinense 1: 57. J. Burman, Meinard, Uytwerf, Amsterdam. WEI, C.F. 1988. Arenga micrantha from China. Acta Phytotaxonomica Sinica 26 (5): 404. 2004] MOGEA: Four new species of Arenga from Indonesia 189 WEI, C. F. 1989. A new species of Arenga from China. Acta Botanica Sinica 4: 7– 9. WENDLAND, H. & O. DRUDE. 1878. Index Generalis in O. KERCHOVE DE DENTERGHEM (Editor), Les Palmiers. J. Rothschild. Paris. WENDLAND, H. & O. DRUDE. 1883. Palmae. In. BENTHAM, G & HOOKER, J.D. (Editors). Genera Plantarum 3: 870 – 948. L. Reeve & Co. London. WHITMORE, T.C. 1970. Taxonomic Notes on some Malayan Palms. Principes 14: 123 – 12. INSTRUCTION TO AUTHORS Manuscripts intended for publication in Reinwardtia should be written either in English, French or German, and represent articles which have not been published in any other journal or proceedings. Each manuscript received will be considered and processed further if it is accompanied by signed statements given independently by two reviewers chosen by the author(s) attesting to its merits as well as its scientific suitability for publication in Reinwardtia. Two printed copies (on A4 paper) of the manuscript of not more than 200 pages should be sent to Editors, together with an electronic copy prepared on Word Processor computer programme using Times New Romance letter type and saved as Rich Text File must be submitted. For the style of presentation authors should follow the latest issue of Reinwardtia very closely. Title of the article should be followed by author's name and mailing address and a one-paragraphed abstract in English (with French or German abstract for papers in French or German) of not more than 250 words. Keywords should be given below each abstract. On a separate paper author(s) should prepare the preferred running title of the article submitted. Taxonomic keys should be prepared using the aligned-couplet type. Strict adherence to the International Code of Botanical Nomenclature is observed, so that taxonomic and nomenclatural novelties should be clearly shown, Latin description for new taxon proposed should be provided, and the herbaria where type specimens are deposited should be indicated. Synonyms should be presented in the long form [name of taxon, author's name, year of publication, abbreviated journal or book title, volume (number): [page]. Maps, line drawing illustrations or photographs preferably should be prepared in landscape presentation to occupy two columns. Illustrations must be submitted as original art accompanying, but separate from, the manuscripts. On electronic copy, the illustrations should be saved in jpg or .gif format. Legends for illustrations must be submitted separately at the end of the manuscript. Bibliography, list of literature cited or references follow the Harvard System. For each paper published author(s) will receive 25 copies of reprints free of charge. Any additional copies should be ordered in advance and the author(s) will be charged accordingly. ISSN 0034-365 X REINWARDTIA Vol. 12. No. 2. 2004 CONTENTS Page W.J.J.O. DE WILDE & BRIGITTA E.E. DUYFJES. Kedrostis Medik. (Cucurbitaceae) in Asia .'. - 129 J.F. VELDKAMP. Miscellaneous notes on mainly Southeast Asian Gramineae... 135 PITRA AKHRIADI, HERNAWATI AND RUSJDITAMIN. A new species of Nepenthes (Nepenthaceae) from Sumatra - 141 KUSWATA KARTAWINATA, ISMAYADI SAMSOEDIN, M. HERIYANTO AND J.J. AFRIASTINI. A tree species inventory in a one-hectare plot at the Batang Gadis National Park, North Sumatra, Indonesia .. 145 E.A.P. ISKANDAR & J.F. VELDKAMP. A revision of Malesian Isachne sect. Isachne (Gramineae, Panicoideae, Is.ach.neae) ' 159 JOHANIS P. MOGEA. Four new species pf Arenga (Palmae) from Indonesia 181 J.F. VELDKAMP. The correct name for Pyrrosia hastata Ching (Polypodiaceae, Pteridophyta) ..... 191 TRI MULYANINGSIH & COLIN ERNEST RIDSDALE. An additional species of Villaria Rolfe {Rubiaceae') from The Philippines 195 ELIZABETH A. WIDJAJA, INGGIT PUDJI ASTUTI & IDA BAGUS KETUT ARINASA. New species of bamboos (Poaceae-Bambusoideae) from Bali 199 HERBARIUM BOGORIENSE BIDANG BOTANI PUSAT PENELITIAN BIOLOGI - LIPI BOGOR, INDONESIA covD 67-136-1-SM JOHANIS P. MOGEA Herbarium Bogoriense, Bidang Botani, Puslit Biologi – LIPI, ABSTRACT ABSTRAK ACKNOWLEDGEMENTS REFERENCES covbel