Phytotaxa 159 (4): 287–290 www.mapress.com / phytotaxa / Copyright © 2014 Magnolia Press ISSN 1179-3155 (print edition) Article PHYTOTAXA ISSN 1179-3163 (online edition) http://dx.doi.org/10.11646/phytotaxa.159.4.5 Salacca acehensis (Arecaceae), A New Species from Sumatra, Indonesia ZUMAIDAR 1,2 , TATIK CHIKMAWATI 3 , ALEX HARTANA 3,4 , SOBIR 5 , JOHANIS P. MOGEA 6 & FINN BORCHSENIUS7 1 Plant Biology Graduate Program, Department of Biology, Faculty of Mathematics and Natural Sciences, Bogor Agricultural University, Darmaga Campus, Bogor 16680, Indonesia. 2 Department of Biology, Mathematics and Sciences Faculty, Syiah Kuala University, Jl. Syech Abdur Rauf, Darussalam Banda Aceh, Indonesia. Email: zumaidar@yahoo.com 3 Department of Biology, Faculty of Mathematics and Natural Sciences, Bogor Agricultural University, Darmaga Campus, Bogor 16680, Indonesia. Email: tchikmawati@yahoo.com 4 Email: ahartana@indo.net.id 5 Department Agronomy and Horticulture, Bogor Agricultural University, Darmaga Campus, Bogor 16680, Indonesia Email: sobir@ipb.ac.id 6 Herbarium Bogoriense, Botany Division, Research Center for Biology, Indonesian Institute of Sciences, Jl Raya Jakarta Bogor Km 47, Cibinong, Indonesia. 7 Science Museums, Aarhus University, Building 1137 Universitetsparken, DK-8000 Aarhus C, Denmark. Email: finn.borchsenius@biology.au.dk. Abstract A new species of Salacca sect. Salacca from Sumatra is described and illustrated. It is characterized by dwarf habit, with leaves to 2.5 m long; erect and slender staminate inflorescences to 7 cm long; and small infructescences, to 10 cm long, with up to 3 branches The most similar species, S. rupicola from Borneo, is different in having the apical leaflets composed ca. 8 united segments versus 2 in the new species, and in having larger inflorescences, the staminate to 15 cm long and the pistillate to 40 cm long. Key words:Aceh, dwarf salak, Gunung Leuser National Park, section Salacca Introduction Salacca Reinwardt (1825: 3; Arecaceae, subfamily Calamoideae, tribe Calameae) comprises 22 species (Govaerts et al. 2013) distributed from Burma and Indochina south and eastwards to Borneo, Java and the southern most part of the Philippines (Dransfield et al. 2008) with the largest number of species and the greatest morphological diversity found in the Malay Peninsula and Borneo. Although there are widespread species, such as S. affinis Griffith (1845: 9) and S. zalacca Voss (1895: 1152), most of the species are restricted to very small areas (Dransfield 2009).The genus is neatly divisible into two sections (Beccari 1918; Dransfield et al. 2008): section Salacca with strigose ovary, hispid subspinous fruit, and pistillate rachillae bearing dyads of one fertile pistillate and one sterile staminate flower; and section Leiosalacca with ovaries and fruits covered in smooth scales, and pistillate rachillae bearing solitary pistillate flowers. Of the 22 species currently recognized, 20 belong to section Salacca and two to section Leiosalacca (Dransfield et al. 2008). In this paper we describe a new species first collected by J. Dransfield and D. Saerudin at Gunung Kemiri, Southeast Aceh Regency, Aceh Province in 1971. The species was later recollected by one of the authors of this paper (JM) who annotated the specimens with the name S. acehensis. However, the name remained unpublished. In this paper we describe the new species and compare it to other small species of section Salacca. Accepted by Timothy Evans: 19 Dec. 2013; published: 18 Feb. 2014 Licensed under a Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0 287 Taxonomic treatment Salacca acehensis Mogea & Zumaidar sp.nov. Type:—INDONESIA. Sumatra: Aceh Province, Southeast Aceh Regency, Gunung Kemiri, hillslope of dipterocarp forest, 900 m elevation,18 November 1975, J.P.Mogea 568 (holotype BO!, isotypes K!, L!). Small palm, with stem to 15 cm tall and leaves 1–2.5 m long. Staminate inflorescences slender and erect, to 7 cm long, with up to 3 branches. Pistillate inflorescenses to 10 cm long, with up to 2 branches. Most similar to S. rupicola J. Dransf. from Borneo, but different in having the apical leaflets composed of ca. 2 united segments (versus 8 in S. rupicola), and smaller inflorescences (the staminate inflorescence up to15 cm long and the pistillate ones to 40 cm long in S. rupicola). FIGURE 1. Salacca acehensis sp. nov. A. Stem with infructescence; B. Leaf tip. Drawn from holotype, J.P. Mogea 568 (BO), by Anne Kusuma. 288 • Phytotaxa 159 (4) © 2014 Magnolia Press ZUMAIDAR Small, pleonanthic, dioecious palm. Stems clustering, ca. 10–15 cm long, 3–5 cm in diameter, somewhat stilt rooted, obscured by persistent leaf bases. Leaves 5–12 per stem, 1–2.5 m long; sheath 5–6 cm wide at the base, densely covered abaxially with dark brown indumentum, armed in the middle part with comb-shaped groups of spines, each group consisting of 4–5 stout, triangular, yellowish spines, to 25 mm long and 2 mm wide at the base, smaller spines present between the groups; all spines covered in indumentum, especially on adaxial side; petiole slender, 75–125 cm long, ca. 9 mm in diameter at the base, 5 mm in diameter in the middle, triangular, covered in pale brown to dark brown indumentum, especially in abaxial side, armed with scattered groups of short horizontal and reflexed spines arranged in three longitudinal rows; rachis to 60 cm long. Leaflets 10–12 on each side of the blade, irregularly arranged in groups of 2–3 near the base, spreading in several planes, sigmoid to lanceolate, acuminate, margins armed with small curved spines ca. 0.5 mm long inserted at distances of 3–5 mm, pointing upwards, adaxial surface dark green with sparse brown indumentum, abaxial surface yellowish grey, with dark brown indumentum at the base and the margins; middle leaflets to 32 cm long and 6 cm wide, with 3 main longitudinal veins separated by 1–2 cm and 4–7 minor veins in between, adaxially with transverse veinlets conspicuous; apical leaflet 10 cm wide on each side, with ca. 2 main folds. Inflorescences axillary, piercing the subtending leaf sheath. Staminate inflorescence to 7 cm long, slender and erect, simple or with up to 3 branches to 5 cm long, with flowers borne in dyads, each subtended by a short bracteole. Staminate flowers with sepals 3, membranous, ca. 3 mm long and 2 mm wide, basally united and with a dense indumentum; petals 3, connate in the basal half, pink outside, basally white inside, ca. 2 mm long and 1 mm wide; stamens 6, ca. 1 mm long, filament red, anther ca. 1 mm long with yellow pollen. Pistillate inflorescence and flowers not seen. Young infructescences to 10 cm long, simple or with up to 2 branches, closely sheathed by several peduncular bracts. Developing fruits globose, ca. 7 mm long and 8 mm wide (in dry condition), densely covered with ascendent scales, ca. 3.5 mm long and 1 mm wide. Paratypes:—INDONESIA. Sumatra; Aceh Province, Southeast Aceh Regency, Gunung Kemiri, near junction of hill dipterocarp forest and lower montane forest, steep valley side, 1200 m elevation, 27 August 1971, J. Dransfield and D. Saerudin 1983 (K!, KYO); same locality, hillslope of dipterocarp forest, 900 m elevation, 18 November 1975, J.P. Mogea 569 (BO!), 570 (BO!), 572 (BO!), 573 (BO!), 574 (BO!); North Sumatra Province, Bukit Lawang Bahorok, Langkat, hill dipterocarp forest, 200 m elevation, 25 February 1973, J. Dransfield 3310 (BO!). Discussion:—Salacca acehensis has the epicarp covered in spine-like scales and thus clearly belongs to section Salacca. Among the species of that section it mostly resembles S. rupicola Dransfield (1980: 36), with which it shares the small size, pinnate leaves and slender, erect, staminate inflorescences. However, S. rupicola has a narrow, bluish green leaves with flabellate apical leaflets composed of ca. 8 united segments while in S. acehensis they are composed of ca. 2. Furthermore, inflorescences of S. rupicola are larger: the staminate ones are up to 15 cm long (versus 7 cm in S. acehensis) and the pistillate up to 40 cm (versus 10 cm in S. acehensis). Salacca rupicola also occurs in limestone habitats in Borneo. Of the remaining species of section Salacca with leaves less than 2.5 m long, two species from Borneo, viz. S. dransfieldiana Mogea (1980: 463) and S. sarawakensis Mogea (1980:473), and three species from Peninsular Malaysia, viz. S. flabellata Furtado (1949: 387), S. minuta Mogea (1984: 11) and S. multiflora Mogea (1984: 13), have bifid, flabellate leaves. The remaining small species, S. bakeriana Dransfield (2009: 168) from Borneo, S. graciliflora Mogea (1984: 6) from Peninsular Malaysia and S. stolonifera Hodel (1997: 35) from Thailand, all have relatively long male inflorescences, up to 0.7–1.2 m long, depending on the species, that are held along the surface of the ground and sometimes produce new shoots at the tip —a character also found in S. flabellata). This has not been observed in S. acehensis where male inflorescences are small and erect. A duplicate of the paratype collection J. Dransfield and D. Saerudin 1983 was distributed to BO (J. Dransfield pers. comm.) but was not found there in spite of thorough search. Conservation status:—Gunung Kemiri, where this new species was first discovered, is part of the large, 1.09 mill. ha. Gunung Leuser National Park in northern Sumatra and hence protected area. The second known locality is located at the eastern edge of that park, some 65 km E of Gunung Kemiri. The habitat is hill dipterocarp forest up to an elevation of ca. 1200 m and Salacca acehensis may occur in large parts of the park. Data are insufficient to perform a proper evaluation of its conservation status according to the IUCN criteria, but given the apparently small total extent of the species’ range, and the high rates of deforestation outside protected area, it may be vulnerable or even endangered. SALACCA ACEHENSIS, A NEW SPECIES FROM SUMATRA, INDONESIA Phytotaxa 159 (4) © 2014 Magnolia Press • 289 Acknowledgements We are grateful to John Dransfield, William J. Baker, and Lauren Gardiner at the Royal Botanic Gardens, Kew for their help and advice in connection with this study.The first author would like to thank Dikti (the Directorate General of Higher Education, Indonesia) for sponsoring her study and her Sandwich Program 2012 at Aarhus University, Denmark; Mien A. Rifai as her supervisors at Bogor Agricultural University for his wise guidance, advice, attention, patience and support during her study; Peter van Welzen, G. Thijsse, and P.A.J. Audiffred at Leiden Herbarium for making specimens available; Himmah Rustiami at Herbarium Bogoriense for kind help with her study. Thanks are also due to Anne Kusuma for making the drawing. References Beccari, O. (1918) Asiatic palms—Lepidocaryeae. Part III. Annals of the Royal Botanic Garden 12(2). The Bengal Secretariat Book Depot, Calcutta. 231 pp. Dransfield, J. (1980) A new species of Salacca Reinw. from the limestone of the Gunung Mulu National Park. Botanical Journal of Linnean Society 81: 36–37. Dransfield, J. (2009). A new species of Salacca from Sarawak. Palms 53: 167–170. Dransfield, J., Uhl, N.W., Asmussen-Lange, C.B., Baker, W.J., Harley, M.M. & Lewis, C.E. (2008) Genera Palmarum. The Evolution and Clasification of Palms. Royal Botanical Gardens, Kew, UK.732 pp. Furtado, C. X., 1949. The Malayan species of Salacca. Gardens Bulletin Singapore 12: 378–403. Govaerts, R., Dransfield, J., Zona, S.F., Hodel, D.R. & Henderson, A. (2013) World checklist of Arecaceae. Facilitated by the Royal Botanical Gardens, Kew. Published on the internet; http://apps.kew.org/wcsp/ Retrieved 04 June 2013. Griffith, W. (1845) The palms of British East India. Calcutta journal of natural history, and miscellany of the arts and sciences in India 5: 1–103. Hodel, D.R. (1997) New species of palms from Thailand. Palm Journal 134: 28–37. Mogea, J.P. (1980) The flabellate-leaved species of Salacca (Palmae). Reinwardtia 9: 461–479. Mogea, J.P. (1984) Three new species of Salacca (Palmae) from the Malay Peninsula. Federation Museums Journal (Kuala Lumpur) 29: 1–19. Reinwardt, C.G.C. (1825) In C. F. Hornschuch, Sylloge Plantarum Novarum Itemque Minus Cognitarum a Praestantissimis Botanicis adhuc Viventibus Collecta et a Societate Regia Botanica Ratisbonensi Edita. Vol. 2. Societate Regia Botanica, Regensburg. Voss, A. (1895) Vilmorin's Blumengärtnerei Beschreibung, Kultur und Verwendung des Gesamten Pflanzenmaterials fur Deutsche Garten. Dritte, neubearbeite Auflage. Part 1. Berlin. http://dx.doi.org/10.5962/bhl.title.67392 290 • Phytotaxa 159 (4) © 2014 Magnolia Press ZUMAIDAR