Abstract
A revision of the ginger genus Geostachys (Zingiberaceae: Alpinioideae: Alpinieae) in Cambodia, Laos and Vietnam is presented. Three species are formally recognised, all endemic to the area of study, including one new species from central Vietnam. Lectotypes are designated for G. annamensis and G. pierreana. The uncertainty about the type locality of G. pierreana is highlighted; the absence of this species in Thailand and Vietnam is demonstrated. The presence of Geostachys in Laos is discussed. The key to the species of the genus is provided. For each species, description, notes on etymology/eponymy, distribution, IUCN preliminary assessment, habitat and phenology, and taxonomy are given. The newly described species, G. aristata, is compared to the morphologically closest congener, G. annamensis, from which it differs by green leaf sheaths and ligules, greenish bracts and bracteoles with prominently aristate apices, prominently mucronate calyx lobes and labellum with crimson spots extending to the margins.
References
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<p>Cho, S.H., Chhang, P. & Kim, Y.D. (2016) <em>A checklist for the seed plants of Cambodia</em>. National Institute of Biological Resources, Ministry of Environment, Incheon, 272 pp.</p>
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<p> </p>
<p>Gagnepain, F. (1906b) Notice biographique sur J.-B.-Louis Pierre. <em>Bulletin de la Société Botanique de France</em> 53 (1): 54–59. https://doi.org/10.1080/00378941.1906.10831140</p>
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<p>Larsen, K., Lock, J.M., Maas, H. & Maas, P.J.M. (1998) Zingiberaceae. <em>In</em>: Kubitzki, K. (Ed.) <em>The Families and Genera of Vascular Plants</em>, vol 4. Springer, Berlin, Heidelberg, pp. 474–495. https://doi.org/10.1007/978-3-662-03531-3_49</p>
<p>Lau, K.H. & Lim, C.K. (2012) Revision of the genus <em>Geostachys</em> (Zingiberaceae) in Peninsular Malaysia. <em>Folia Malaysiana</em> 13 (1): 7–42.</p>
<p>Lau, K.H., Lim, C.K. & Mat-Salleh, K. (2007) Materials for a taxonomic revision of <em>Geostachys</em> (Baker) Ridl. (Zingiberaceae) in Peninsular Malaysia. <em>Gardens’ Bulletin Singapore</em> 59 (1&2): 129–138. [https://www.nparks.gov.sg/sbg/research/publications/gardens’-bulletin-singapore/-/media/sbg/gardens-bulletin/4-4-59-1-2-13-y2007-v59-p1-p2-gbs-pg-129.ashx]</p>
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<p>Leong-Škorničková, J., Nguyễn, Q.B., Trần H.Đ. & Záveská, E. (2016) <em>Etlingera poulsenii </em>and <em>Hornstedtia bella </em>(Zingiberaceae: Alpinieae)<em>, </em>two new species from central Vietnam<em>. Gardens’ Bulletin Singapore </em>68 (2): 287–297. https://doi.org/10.3850/S2382581216000223</p>
<p>Leong-Škorničková, J., Trần, H.Ð., Nguyễn, Q.B., Hlavatá, K., Lưu, H.T., Nguyễn, Q.Ð., Nguyễn, T.T. & Newman, M. (2019) The identity of <em>Amomum trilobum </em>and <em>Amomum unifolium </em>(Zingiberaceae: Alpinioideae), and description of four new related species from Vietnam. <em>Phytotaxa </em>401 (3): 149–165. https://doi.org/10.11646/phytotaxa.401.3.1</p>
<p>Lim, C.K. & Lau, K.H. (2006) A new <em>Geostachys</em> species from Maliau Basin, Sabah. <em>Folia Malaysiana</em> 7 (1&2): 33–40.</p>
<p>Mayoe, J. (2010) A new species of <em>Geostachys</em> Ridl. (Zingiberaceae) from Southern Thailand. <em>Taiwania</em> 55 (1): 8–12. https://doi.org/10.6165/tai.2010.55(1).8</p>
<p>McNeill, J. (2014) Holotype specimens and type citations: general issues. <em>Taxon</em> 63: 1112–1113. http://dx.doi.org/10.12705/635.7</p>
<p>Miller, P. (1754) <em>The Gardeners Dictionary</em>, ed. 4, vol. 3. John and James Rivington, London, unpaginated. https://doi.org/10.5962/bhl.title.79061</p>
<p>Newman, M., Lhuillier, A. & Poulsen, A.D. (2004) Checklist of the Zingiberaceae of Malesia. <em>Blumea</em> Supplement 16: 1–166. [https://repository.naturalis.nl/pub/603330/Blumea_supplement_16.pdf]</p>
<p>Newman, M., Ketphanh, S., Svengsuksa, B., Thomas, P., Sengdala, K., Lamxay, V. & Armstong, K. (2007) <em>A Checklist of the Vascular Plants of Lao PDR</em>. Royal Botanic Garden Edinburgh, Edinburgh, 394 pp.</p>
<p>Nguyễn, Q.B. (2005) 245. Zingiberaceae Lindl. 1835. – Họ Gừng. <em>In</em>: Nguyễn, T.B. (Ed.) <em>Checklist of Plant Species of Vietnam</em>, Vol. 3. Agriculture Publishing House, Hanoi, pp. 487–587. [in Vietnamese]</p>
<p>Nguyễn, Q.B. (2017) <em>Flora of Vietnam 21: Zingiberaceae Lindl</em>. Publishing House for Science and Technology, Hanoi, 469 pp. [in Vietnamese]</p>
<p>Olander, S.B. (2019a) <em>Geostachys annamensis</em>. <em>The IUCN Red List of Threatened Species</em> 2019: e.T117327020A124282492. https://dx.doi.org/10.2305/IUCN.UK.2019-2.RLTS.T117327020A124282492.en.</p>
<p>Olander, S.B. (2019b) <em>Geostachys pierreana</em>. <em>The IUCN Red List of Threatened Species</em> 2019: e.T117327601A124282562. https://dx.doi.org/10.2305/IUCN.UK.2019-2.RLTS.T117327601A124282562.en. </p>
<p>Phạm, H.H. (2003) <em>Cây cỏ Việt Nam, an illustrated Flora of Vietnam. </em>Vol. 3. Youth Publication, Ho Chi Minh City, 1020 pp. [in Vietnamese]</p>
<p>Picheansoonthon, C. & Mayoe, J. (2011) <em>Geostachys tratensis</em> (Zingiberaceae): A new species from Eastern Thailand. <em>Journal of Japanese Botany</em> 86: 133–138. [http://www.jjbotany.com/pdf/JJB_086_133_138_abstract.pdf]</p>
<p>POWO (2023) Plants of the World Online. Facilitated by the Royal Botanic Gardens, Kew. Published on the Internet. Available from: http://www.plantsoftheworldonline.org/ (accessed 20 January 2023)</p>
<p>Ridley, H.N. (1899) The Scitamineae of the Malay Peninsula. <em>Journal of the Straits Branch Royal Asiatic Society </em>32: 85–184. [https://www.biodiversitylibrary.org/item/130396#page/9/mode/1up]</p>
<p>Ridley, H.N. (1909) The flora of the Telôm and Padang valleys. <em>Journal of the Federated Malay States Museums</em> 4: 1–98. [https://www.biodiversitylibrary.org/item/62879#page/13/mode/1up]</p>
<p>Roxburgh, W. (1820) <em>Plants of the coast of Coromandel</em>, Vol. 3. W. Bulmer and Co., London. https://doi.org/10.5962/bhl.title.467</p>
<p>Saensouk, P. & Saensouk, S. (2021) Taxonomic studies and three new records on genus <em>Geostachys </em>(Baker) Ridl. in Thailand. <em>Biodiversitas</em> 22 (7): 3057–3067. https://doi.org/10.13057/biodiv/d220760</p>
<p>Stone, H.C. (1980) Additions to the Malayan flora. N. 7. A new <em>Geostachys </em>(Zingiberaceae) from Gunung Ulu Kali, Pahang. Malaysia. <em>Malaysian Journal of Science </em>6 (A): 75–81.</p>
<p>Turland, N.J., Wiersema, J.H., Barrie, F.R., Greuter, W., Hawksworth, D.L., Herendeen, P.S., Knapp, S., Kusber, W.-H., Li, D.-Z., Marhold, K., May, T.W., McNeill, J., Monro, A.M., Prado, J., Price, M.J. & Smith, G.F. (2018) <em>International Code of Nomenclature for algae, fungi, and plants (Shenzhen Code) adopted by the Nineteenth International Botanical Congress Shenzhen, China, July 2017. Regnum Vegetabile 159.</em> Koeltz Botanical Books, Glashütten, 254 pp. https://doi.org/10.12705/Code.2018</p>
<p>Turner, I.M. (2000) The plant taxa of H.N. Ridley, 3. The Zingiberales. <em>Asian Journal of Tropical Biology</em> 4 (1): 1–47.</p>
<p>Valeton, T. (1921) <em>Rhynchanthus</em> Hook. f., <em>Geanthus</em> Reinw. and <em>Geostachys </em>Ridl<em>. Bulletin du Jardin Botanique de Buitenzorg Ser. III</em>, 3: 141–147. [https://www.biodiversitylibrary.org/item/155654#page/159/mode/1up]</p>
<p>van Steenis-Kruseman, M.J. & van Steenis, C.G.G.J. (1950) Malaysian plant collectors and collections being a cyclopaedia of botanical exploration in Malaysia and a guide to the concerned literature up to the year 1950. <em>In: </em>van Steenis, C.G.G.J. (Ed.) <em>Flora Malesiana</em>, ser. 1, Spermatophyta, vol. 1. Hoordhoff-Kolff, Djakarta, pp. 1–639.</p>
<p>Bachman, S., Moat, J., Hill, A.W., de la Torre, J. & Scott, B. (2011) Supporting Red List threat assessments with GeoCAT: geospatial conservation assessment tool. e-Infrastructures for data publishing in biodiversity science. <em>ZooKeys</em> 150: 117–126. (Version BETA)<sup>* </sup>https://doi.org/10.3897/zookeys.150.2109</p>
<p>Bai, L., Leong-Škorničková, J. & Xia, N. (2015) Taxonomic studies on <em>Zingiber</em> (Zingiberaceae) in China I: <em>Zingiber kerrii</em> and the synonymy of <em>Z. menghaiense</em> and <em>Z. stipitatum.</em> <em>Gardens’ Bulletin Singapore</em> 67 (1): 129–142. https://doi.org/10.3850/S2382581215000149</p>
<p>Baker, J.G. (1892) <em>Alpinia</em>. <em>In</em>: Hooker, J.D. (Ed.) <em>Flora of British India</em>, vol. 6. Reeve, London, pp. 252–257. [https://www.biodiversitylibrary.org/item/61981#page/7/mode/1up]</p>
<p>Baker, E.G., Moore, S., Rendle, A.B., Ridley, H.N. & Wernham, H.F. (1921) On plants from South Annam. <em>The Journal of the Natural History Society of Siam</em> 4 (3): 109–160. [https://thesiamsociety.org/wp-content/uploads/2020/03/NHBSS_004_3c_Baker_OnPlantsFromSouthAn.pdf]</p>
<p>Beentje, H. (2016) <em>The Kew Plant Glossary, an illustrated dictionary of plant terms </em>(second edition)<em>.</em> Royal Botanic Gardens, Kew, 184 pp.</p>
<p>Cho, S.H., Chhang, P. & Kim, Y.D. (2016) <em>A checklist for the seed plants of Cambodia</em>. National Institute of Biological Resources, Ministry of Environment, Incheon, 272 pp.</p>
<p>Gagnepain, F. (1906a) Zingibéracées nouvelles de l’herbier du Muséum (15° note). <em>Bulletin de la Société Botanique de France</em> 53 (2): 132–150. https://doi.org/10.1080/00378941.1906.10831155</p>
<p> </p>
<p>Gagnepain, F. (1906b) Notice biographique sur J.-B.-Louis Pierre. <em>Bulletin de la Société Botanique de France</em> 53 (1): 54–59. https://doi.org/10.1080/00378941.1906.10831140</p>
<p>Gagnepain, F. (1908) Zingibéracées. <em>In</em>: Lecomte, H. (Ed.) <em>Flore Générale de l’Indo-Chine</em>, vol. 6. Masson and Co, Paris, pp. 25–121.</p>
<p>Holttum, R.E. (1950) The Zingiberaceae of the Malay Peninsula. <em>Gardens’ Bulletin Singapore</em> 13: 224–236. [https://www.nparks.gov.sg/sbg/research/publications/gardens’-bulletin-singapore/-/media/sbg/gardens-bulletin/4-4-13-0-01-y1950-v13-gbs-pg-1.ashx]</p>
<p>IUCN Standards and Petitions Subcommittee (2022) <em>Guidelines for Using the IUCN Red List Categories and Criteria</em>, version 15. Prepared by the Standards and Petitions Committee. [https://www. iucnredlist.org/resources/redlistguidelines]</p>
<p>Larsen, K. (1962) Studies in Zingiberaceae. The genus <em>Geostachys </em>in Thailand. <em>Botanisk Tidsskrift</em> 58: 43–46.</p>
<p>Larsen, K. (1986) <em>Geostachys angustifolia</em> sp. nov. (Zingiberaceae) from Thailand. <em>Nordic Journal of Botany</em> 6 (1): 31–33. https://doi.org/10.1111/j.1756-1051.1986.tb00857.x</p>
<p>Larsen, K. (2001) <em>Geostachys smitinandii</em> K. Larsen (Zingiberaceae), a new species from Thailand. <em>Thai Forest Bulletin (Botany)</em> 29: 17–22. [https://li01.tci-thaijo.org/index.php/ThaiForestBulletin/article/view/24865]</p>
<p>Larsen, K., Lock, J.M., Maas, H. & Maas, P.J.M. (1998) Zingiberaceae. <em>In</em>: Kubitzki, K. (Ed.) <em>The Families and Genera of Vascular Plants</em>, vol 4. Springer, Berlin, Heidelberg, pp. 474–495. https://doi.org/10.1007/978-3-662-03531-3_49</p>
<p>Lau, K.H. & Lim, C.K. (2012) Revision of the genus <em>Geostachys</em> (Zingiberaceae) in Peninsular Malaysia. <em>Folia Malaysiana</em> 13 (1): 7–42.</p>
<p>Lau, K.H., Lim, C.K. & Mat-Salleh, K. (2007) Materials for a taxonomic revision of <em>Geostachys</em> (Baker) Ridl. (Zingiberaceae) in Peninsular Malaysia. <em>Gardens’ Bulletin Singapore</em> 59 (1&2): 129–138. [https://www.nparks.gov.sg/sbg/research/publications/gardens’-bulletin-singapore/-/media/sbg/gardens-bulletin/4-4-59-1-2-13-y2007-v59-p1-p2-gbs-pg-129.ashx]</p>
<p>Leong-Škorničková, J. & Newman, M.F. (2015) <em>Gingers of Cambodia, Laos and Vietnam</em>. Singapore Botanic Gardens, National Parks Board, in association with Royal Botanic Garden Edinburgh and Pha Tad Ke Botanical Garden, Singapore, 229 pp.</p>
<p>Leong-Škorničková, J., Nguyễn, Q.B., Trần H.Đ. & Záveská, E. (2016) <em>Etlingera poulsenii </em>and <em>Hornstedtia bella </em>(Zingiberaceae: Alpinieae)<em>, </em>two new species from central Vietnam<em>. Gardens’ Bulletin Singapore </em>68 (2): 287–297. https://doi.org/10.3850/S2382581216000223</p>
<p>Leong-Škorničková, J., Trần, H.Ð., Nguyễn, Q.B., Hlavatá, K., Lưu, H.T., Nguyễn, Q.Ð., Nguyễn, T.T. & Newman, M. (2019) The identity of <em>Amomum trilobum </em>and <em>Amomum unifolium </em>(Zingiberaceae: Alpinioideae), and description of four new related species from Vietnam. <em>Phytotaxa </em>401 (3): 149–165. https://doi.org/10.11646/phytotaxa.401.3.1</p>
<p>Lim, C.K. & Lau, K.H. (2006) A new <em>Geostachys</em> species from Maliau Basin, Sabah. <em>Folia Malaysiana</em> 7 (1&2): 33–40.</p>
<p>Mayoe, J. (2010) A new species of <em>Geostachys</em> Ridl. (Zingiberaceae) from Southern Thailand. <em>Taiwania</em> 55 (1): 8–12. https://doi.org/10.6165/tai.2010.55(1).8</p>
<p>McNeill, J. (2014) Holotype specimens and type citations: general issues. <em>Taxon</em> 63: 1112–1113. http://dx.doi.org/10.12705/635.7</p>
<p>Miller, P. (1754) <em>The Gardeners Dictionary</em>, ed. 4, vol. 3. John and James Rivington, London, unpaginated. https://doi.org/10.5962/bhl.title.79061</p>
<p>Newman, M., Lhuillier, A. & Poulsen, A.D. (2004) Checklist of the Zingiberaceae of Malesia. <em>Blumea</em> Supplement 16: 1–166. [https://repository.naturalis.nl/pub/603330/Blumea_supplement_16.pdf]</p>
<p>Newman, M., Ketphanh, S., Svengsuksa, B., Thomas, P., Sengdala, K., Lamxay, V. & Armstong, K. (2007) <em>A Checklist of the Vascular Plants of Lao PDR</em>. Royal Botanic Garden Edinburgh, Edinburgh, 394 pp.</p>
<p>Nguyễn, Q.B. (2005) 245. Zingiberaceae Lindl. 1835. – Họ Gừng. <em>In</em>: Nguyễn, T.B. (Ed.) <em>Checklist of Plant Species of Vietnam</em>, Vol. 3. Agriculture Publishing House, Hanoi, pp. 487–587. [in Vietnamese]</p>
<p>Nguyễn, Q.B. (2017) <em>Flora of Vietnam 21: Zingiberaceae Lindl</em>. Publishing House for Science and Technology, Hanoi, 469 pp. [in Vietnamese]</p>
<p>Olander, S.B. (2019a) <em>Geostachys annamensis</em>. <em>The IUCN Red List of Threatened Species</em> 2019: e.T117327020A124282492. https://dx.doi.org/10.2305/IUCN.UK.2019-2.RLTS.T117327020A124282492.en.</p>
<p>Olander, S.B. (2019b) <em>Geostachys pierreana</em>. <em>The IUCN Red List of Threatened Species</em> 2019: e.T117327601A124282562. https://dx.doi.org/10.2305/IUCN.UK.2019-2.RLTS.T117327601A124282562.en. </p>
<p>Phạm, H.H. (2003) <em>Cây cỏ Việt Nam, an illustrated Flora of Vietnam. </em>Vol. 3. Youth Publication, Ho Chi Minh City, 1020 pp. [in Vietnamese]</p>
<p>Picheansoonthon, C. & Mayoe, J. (2011) <em>Geostachys tratensis</em> (Zingiberaceae): A new species from Eastern Thailand. <em>Journal of Japanese Botany</em> 86: 133–138. [http://www.jjbotany.com/pdf/JJB_086_133_138_abstract.pdf]</p>
<p>POWO (2023) Plants of the World Online. Facilitated by the Royal Botanic Gardens, Kew. Published on the Internet. Available from: http://www.plantsoftheworldonline.org/ (accessed 20 January 2023)</p>
<p>Ridley, H.N. (1899) The Scitamineae of the Malay Peninsula. <em>Journal of the Straits Branch Royal Asiatic Society </em>32: 85–184. [https://www.biodiversitylibrary.org/item/130396#page/9/mode/1up]</p>
<p>Ridley, H.N. (1909) The flora of the Telôm and Padang valleys. <em>Journal of the Federated Malay States Museums</em> 4: 1–98. [https://www.biodiversitylibrary.org/item/62879#page/13/mode/1up]</p>
<p>Roxburgh, W. (1820) <em>Plants of the coast of Coromandel</em>, Vol. 3. W. Bulmer and Co., London. https://doi.org/10.5962/bhl.title.467</p>
<p>Saensouk, P. & Saensouk, S. (2021) Taxonomic studies and three new records on genus <em>Geostachys </em>(Baker) Ridl. in Thailand. <em>Biodiversitas</em> 22 (7): 3057–3067. https://doi.org/10.13057/biodiv/d220760</p>
<p>Stone, H.C. (1980) Additions to the Malayan flora. N. 7. A new <em>Geostachys </em>(Zingiberaceae) from Gunung Ulu Kali, Pahang. Malaysia. <em>Malaysian Journal of Science </em>6 (A): 75–81.</p>
<p>Turland, N.J., Wiersema, J.H., Barrie, F.R., Greuter, W., Hawksworth, D.L., Herendeen, P.S., Knapp, S., Kusber, W.-H., Li, D.-Z., Marhold, K., May, T.W., McNeill, J., Monro, A.M., Prado, J., Price, M.J. & Smith, G.F. (2018) <em>International Code of Nomenclature for algae, fungi, and plants (Shenzhen Code) adopted by the Nineteenth International Botanical Congress Shenzhen, China, July 2017. Regnum Vegetabile 159.</em> Koeltz Botanical Books, Glashütten, 254 pp. https://doi.org/10.12705/Code.2018</p>
<p>Turner, I.M. (2000) The plant taxa of H.N. Ridley, 3. The Zingiberales. <em>Asian Journal of Tropical Biology</em> 4 (1): 1–47.</p>
<p>Valeton, T. (1921) <em>Rhynchanthus</em> Hook. f., <em>Geanthus</em> Reinw. and <em>Geostachys </em>Ridl<em>. Bulletin du Jardin Botanique de Buitenzorg Ser. III</em>, 3: 141–147. [https://www.biodiversitylibrary.org/item/155654#page/159/mode/1up]</p>
<p>van Steenis-Kruseman, M.J. & van Steenis, C.G.G.J. (1950) Malaysian plant collectors and collections being a cyclopaedia of botanical exploration in Malaysia and a guide to the concerned literature up to the year 1950. <em>In: </em>van Steenis, C.G.G.J. (Ed.) <em>Flora Malesiana</em>, ser. 1, Spermatophyta, vol. 1. Hoordhoff-Kolff, Djakarta, pp. 1–639.</p>