Abstract
A new species of Diospyros, D. laoensis, from Nam Kading National Protected Area, central Laos, is described and illustrated. It morphologically resembles D. longipilosa of Thailand, D. martabanica of India and Southeast Asia, and D. xishuangbannaensis of China, but is distinguished by its adaxially glabrous midrib, shorter calyx lobes and shorter fruiting pedicel. DNA barcodes of the rbcL and matK regions, a vernacular name and preliminary conservation assessment are also provided. As the species is considered to be endemic to a restricted area which is under threat from deforestation, it is here suggested for assessment under the category of Endangered (EN) within the IUCN Red List of Threatened Species.
References
<p class="Reference">Bakhuizen, van den Brink, R.C. (1933) Enumeration of Malayan Ebenaceae. The Gardens’ Bulletin Straits Settlements 7: 161–188.</p><p class="Reference">Candolle, A.P. de. (1844) <em>Prodromus systematis naturalis regni vegetabilis, sive, Enumeratio contracta ordinum generum specierumque plantarum huc usque cognitarium, juxta methodi naturalis, normas digesta</em>, vol. 8. Sumptibus Sociorum Treuttel et Würtz, Paris, 684 pp.</p><p class="Reference">CBOL Plant Working Group (2009) A DNA barcode for land plants.<em> Proceedings of the National Academy of Sciences of the United States of America</em> 106: 12794–12797.</p><p class="Reference"> <a href="https://doi.org/10.1073/pnas.0905845106">https://doi.org/10.1073/pnas.0905845106</a></p><p class="Reference">Clarke, C.B. (1882) Ebenaceae. <em>In:</em> Hooker, J.D. (Ed.) <em>The Flora of British India</em>. Vol. 3. L. Reeve & Co., London, pp. 549–572.</p><p class="Reference">Dick, C.W. & Webb, C.O. (2012) Plant DNA barcodes, taxonomic management, and species discovery in tropical forests. In: Kress, W.J. & Erickson, D.L. (Eds.) DNA Barcodes. Springer, New York, NY. <em>Methods and Protocols</em> 858: 379–393.</p><p class="Reference"> <a href="https://doi.org/10.1007/978-1-61779-591-6_18">https://doi.org/10.1007/978-1-61779-591-6_18</a></p><p class="Reference">Duangjai, S., Wallnöfer, B., Samuel, R., Munzinger, J. & Chase, M.W. (2006) Generic delimitation and relationships in Ebenaceae <em>sensu lato</em>: evidence from six plastid DNA regions.<em> American Journal of Botany</em> 93: 1808–1827.</p><p class="Reference"> <a href="https://doi.org/10.3732/ajb.93.12.1808">https://doi.org/10.3732/ajb.93.12.1808</a></p><p class="Reference">Duangjai, S., Samuel, R., Munzinger, J., Forest, F., Wallnöfer, B., Barfuss, M.H.J., Fischer, G. & Chase, M.W. (2009) A multi-locus plastid phylogenetic analysis of the pantropical genus <em>Diospyros</em> (Ebenaceae), with an emphasis on the radiation and biogeographic origins of the New Caledonian endemic species. <em>Molecular Phylogenetics and Evolution</em> 52: 602–620.</p><p class="Reference"> <a href="https://doi.org/10.1016/j.ympev.2009.04.021">https://doi.org/10.1016/j.ympev.2009.04.021</a></p><p class="Reference">Duangjai, S., Sinbumroong, A. & Suddee, S. (2018) <em>Diospyros phengklaii</em> (Ebenaceae), a new species from south-western Thailand. <em>Thai Forest Bulletin (Botany)</em> 46: 34–39.</p><p class="Reference"> <a href="https://doi.org/10.20531/tfb.2018.46.1.05">https://doi.org/10.20531/tfb.2018.46.1.05</a></p><p class="Reference">Dunning, L.T. & Savolainen, V. (2010) Broad-scale amplification of <em>matK</em> for DNA barcoding plants, a technical note. <em>Botanical Journal of the Linnean Society</em> 164: 1–9.</p><p class="Reference"> <a href="https://doi.org/10.1111/j.1095-8339.2010.01071.x">https://doi.org/10.1111/j.1095-8339.2010.01071.x</a></p><p class="Reference">Gardner, S., Sidisunthorn, P. & Chayamarit, K. (2015) <em>Forest Trees of Southern Thailand, </em>vol. 1. Kobfai Publishing Project, Bangkok, 768 pp.</p><p class="Reference">Hebert, P.D.N. & Gregory, T.R. (2005) The promise of DNA barcoding for taxonomy. <em>Systematic Biology</em> 54: 852–859.</p><p class="Reference"> <a href="https://doi.org/10.1080/10635150500354886">https://doi.org/10.1080/10635150500354886</a></p><p class="Reference">Hiern, W.P. (1873) A monograph of Ebenaceae. <em>Transactions of the Cambridge Philosophical Society</em> 12: 27–300.</p><p class="Reference">Hô, P.H. (1999) <em>Cay Co Viet Nam: An Illustrated Flora of Vietnam,</em> vol. 1. Published by the author, Montreal, 1024 pp. [In Vietnamese]</p><p class="Reference">IUCN (2017) <em>The IUCN Red List of Threatened Species</em>. <em>Version 2017-3</em>. Available from: <a href="http://www.iucnredlist.org">http://www.iucnredlist.org</a> (accessed 25 April 2018)</p><p class="Reference">Kress, W.J., Erickson, D.L., Jones, F.A., Swenson, N.G., Perez, R., Sanjur, O. & Bermingham, E. (2009) Plant DNA barcodes and a community phylogeny of a tropical forest dynamics plot in Panama. <em>Proceedings of the National Academy of Sciences of the United States of America</em> 106 (44): 18621–18626.</p><p class="Reference"> <a href="https://doi.org/10.1073/pnas.0909820106">https://doi.org/10.1073/pnas.0909820106</a></p><p class="Reference">Lecomte, P.H. (1928) Ebénacées nouvelles de L’Indochine. <em>Notulae Systematicae </em>4: 99–121. <em></em></p><p class="Reference">Li, S.-G., Gilbert, M.G. & White, F. (1996) Ebenaceae. <em>In:</em> Wu, Z.Y., Raven, P.H. & Hong D.Y. (Eds.) <em>Flora of China,</em> vol. 15. Missouri Botanical Garden Press, St. Louis and Science Press, Beijing, pp. 215–234. Available from: <a href="http://www.efloras.org">http://www.efloras.org</a> (accessed 1 June 2018)</p><p class="Reference">Merill, E.D. (1909) New or noteworthy Philippine plants, VII. <em>Philippine Journal of Science</em> 4: 247–330.</p><p class="Reference">Merill, E.D. (1923) Diagnosis of Hainan Plants, II. <em>Philippine Journal of Science</em> 23: 237–268.</p><p class="Reference">Merrill, E.D. & Chun, H.Y. (1935) Additions to our knowledge of the Hainan flora, II. <em>Sunyatsenia</em> 2: 203–332.</p><p class="Reference">Newman, M. F., Ketphanh, S, Svengsuka, B., Thomas, P., Sengdala, K., Lamxay, V. & Armstrong, K. (2007)<em> A checklist of the vascular plants of Lao PDR</em>. Royal Botanic Garden Edinburgh, Scotland, UK, 375 pp.</p><p class="Reference">Ng, F.S.P. (2002) Ebenaceae. <em>In</em>: Soepadmo, E., Saw, L.G. & Chung, R.C.K. (Eds.) <em>Tree flora of Sabah and Sarawak</em>, vol. 4. Forest Research Institute Malaysia (FRIM), Kepong, pp. 29–100.</p><p class="Reference">Phengklai, C. (1977) New species of Ebenaceae from Thailand. <em>Natural History Bulletin of the Siam Society</em> 26: 342–344, Plate XII & XIII.</p><p class="Reference">Phengklai, C. (1981) Ebenaceae. <em>In</em>: Smitinand, T. & Larsen, K. (Eds.) <em>Flora of Thailand</em>, vol. 2<em>.</em> The Forest Herbarium, National Park, Wildlife and Plant Conservation Department, Bangkok, pp. 281–392.</p><p class="Reference">Phengklai, C. (2005) Two new species of <em>Diospyros</em> (Ebenaceae) from Thailand. <em>Thai Forest Bulletin (Botany) </em>33: 157–160.</p><p class="Reference">Prosperi, J., Lamxay, V., Hallé, F., Bompard, J.-M., Blanc, P., Ramesh, B. R., Ayyappan, N. & Cardinal, S. (2018) New records in the flora checklist of Laos, resulting from a survey of Phou Hin Poun National Biodiversity Conservation Area. <em>Edinburgh Journal of Botany 75</em>: 91–106.<br /> <a href="https://doi.org/10.1017/S096042861700035X">https://doi.org/10.1017/S096042861700035X</a></p><p class="Reference">Souladeth, P., Tagane, S., Zhang M., Okabe, N. & Yahara, T. (2017) Flora of Nam Kading National Protected Area I: a new species of yellow-flowered <em>Strobilanthes</em> (Acanthaceae), <em>S. namkadingensis</em>. <em>PhytoKeys</em> 81: 11–17.</p><p class="Reference"> <a href="https://doi.org/10.3897/phytokeys.81.13203">https://doi.org/10.3897/phytokeys.81.13203</a></p><p class="Reference">Tagane, S., Souladeth, P., Rueangruea, S., Okabe, N., Zhang, M., Chayer, S., Yang, C.-J. & Yahara, T. (2017) Flora of Nam Kading National Protected Area II: 30 new records of angiosperms for Laos. <em>Edinburgh Journal of Botany </em>75: 107–116.</p><p class="Reference"> <a href="https://doi.org/10.1017/S0960428617000361">https://doi.org/10.1017/S0960428617000361</a></p><p class="Reference">Tagane, S., Souladeth, P., Zhang, M. & Yahara, T. (2018) Flora of Nam Kading National Protected Area IV: Two new species of Annonaceae, <em>Monoon namkadingense</em> and <em>Neo-uvaria laosensis</em>. <em>Phytotaxa</em> 336 (1): 82–88.</p><p class="Reference"> <a href="https://doi.org/10.11646/phytotaxa.336.1.6">https://doi.org/10.11646/phytotaxa.336.1.6</a></p><p class="Reference">Toyama, H., Kajisa, T., Tagane, S., Mase, K., Chhang, P., Samreth, V., Ma, V., Sokh, H., Ichihashi, R., Onoda, Y., Mizoue, N. & Yahara, T. (2015) Effects of logging and recruitment on community phylogenetic structure in 32 permanent forest plots of Kampong Thom, Cambodia. <em>Philosophical Transactions B: Biological Science</em> 370 (1662): 20140008.</p><p class="Reference"> <a href="http://dx.doi.org/10.1098/rstb.2014.0008">http://dx.doi.org/10.1098/rstb.2014.0008</a></p><p class="Reference">Yang, C.-J., Tagane, S., Souladeth, P., Okabe, N., Hu, J.-M. & Yahara, T. (2018) Flora of Nam Kading National Protected Area III: <em>Begonia namkadingensis</em> (Begoniaceae), a new species in limestone area. <em>Phytotaxa</em> 334 (2): 195–199.</p><p class="Reference"> <a href="https://doi.org/10.11646/phytotaxa.334.2.8">https://doi.org/10.11646/phytotaxa.334.2.8</a></p><p class="Reference">Wallnöfer, B. (2001) The biology and systematics of Ebenaceae: a review. <em>Annalen des Naturhistorischen Museums in Wien</em> <em>B</em> 103: 485–512.</p><p class="Reference">Wu, Z.Y. & Zhu, H. (1995) Validation of a new species of <em>Diospyros</em> (Ebenaceae) from Yunnan, China. <em>Novon</em> 5: 296.</p><p class="Reference">Zhu, H. (2017) Floristic characteristics and affinities in Lao PDR, with a reference to the biogeography of the Indochina peninsula.<em> PLOS ONE</em> 12 (6): e0179966.</p><p> <a href="https://doi.org/10.1371/journal.pone.0179966">https://doi.org/10.1371/journal.pone.0179966</a></p>