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Issue: Vol. 748 No. 3: 24 Mar. 2026
Type: Article
Published: 2026-03-24
DOI: 10.11646/phytotaxa.748.3.2
Page range: 258-268
Abstract views: 0
PDF downloaded: 0

Duplipetala hexagona, a new generic record for Laos, and a key to Laotian Gentianaceae

Department of Higher Plants, Biological Faculty, M.V. Lomonosov Moscow State University, 1, 12, Leninskie Gory, 119234 Moscow, Russia; Joint Vietnam-Russia Tropical Science and Technology Research Center, 63, Nguyen Van Huyen street, Cau Giay, 122000 Hanoi, Vietnam
Komarov Botanical Institute of the Russian Academy of Sciences, 2 Prof. Popov street, 197022 St. Petersburg, Russia
Botany Department, State Museum of Natural History Stuttgart, 1 Rosenstein, 70191 Stuttgart, Germany
Canscora Canscorinae checklist Eastern Indochina limestone karst Thailand Vang Vieng town Eudicots

Abstract

A comprehensive revision of morphology, taxonomy and geographical distribution of Duplipetala hexagona, a species of Gentianaceae, is provided. Earlier believed to be endemic to Thailand, the species is here reported from limestone areas of central Laos, representing the first record of the genus Duplipetala in the country. A number of structural traits of D. hexagona are uncovered or clarified; in particular, the pairs of inflorescence bracts are demonstrated to be perfoliate, and the gynophore is described. The morphological description is supplemented for the first time by analytical photographic illustrations. A full list of the available specimens is included, and the distribution of the species is shown on a map. Delimitation between D. hexagona and D. pentanthera is discussed. Diversity of Gentianaceae in Laos is summarized, and keys for identification of the Laotian genera and species of the family are presented.

References

  1. Averyanov, L.V., Nguyen, K.S. & Maisak, T.V. (2019) Plant diversity, flora and vegetation of Hin Nam No protected area. Lambert Academic Publishing, Saarbrucken, 431 pp.
  2. Chen, T., Zhu, H., Chen, J., Taylor, C.M., Ehrendorfer, F., Lantz, H., Funston, A.M. & Puff, C. (2011) Rubiaceae. In: Wu, Z.Y., Raven, P.H. & Hong, D.Y. (Eds.) Flora of China, Vol. 19. Science Press, Beijing & Missouri Botanical Garden, St. Louis, pp. 57–368.
  3. Clarke, C.B. (1906) Materials for a flora of the Malayan Peninsula: Order LXXVIII. Gentianaceae. Journal of the Asiatic Society of Bengal 74: 86–91.
  4. Ho, T.N. & Pringle, J.S. (1995) Gentianaceae. In: Wu, Z.Y. & Raven, P.H. (Eds.) Flora of China, Vol. 16. Science Press, Beijing & Missouri Botanical Garden, St. Louis, pp. 1–139.
  5. Hul, S. (2003) Gentianaceae. In: Morat, Ph. (Ed.) Flore du Cambodge, du Laos et du Viêtnam, Vol. 31. Muséum National D’Histoire Naturelle, Paris, pp. 1–96.
  6. Hul, S. (2007) A new species of Gentiana (Gentianaceae) from Laos. Edinburgh Journal of Botany 64 (2): 173–177. https://doi.org/10.1017/S096042860700090X
  7. Hul, S. (2010) Two new species of Gentianaceae from Indo‑China. Edinburgh Journal of Botany 67 (1): 155–160. https://doi.org/10.1017/S096042860999028X
  8. Jin, H.-Y., Ahn, T.-H., Lee, H.-J., Song, J.H., Lee, C.H., Kim, Y.J., Yoon, J.W., Chamg, K.S., Kang, H.S., Cheng, H.C., Park, J.H., Bang, M., Bouahom, B., Phongoudome, C., Thammavong, V., Souladeth, P., Bouamanivong, S., Phasaysombath, T., Chanthavongsa, K., Lanorsavanh, S. & Sayyalath, S. (2016) A checklist of plants in Lao PDR. Korea National Arboretum of the Korea Forest Service, Pocheon‑si, 403 pp.
  9. Kerr, A.F.G. (1940) Canscora hexagona Kerr. Bulletin of Miscellaneous Information (Royal Botanic Gardens, Kew) 1940 (5): 181. https://doi.org/10.2307/4111491
  10. Lamarck, J.B.A.P. de Monnet de (1785) Encyclopedie Methodique. Botanique, Vol. 1. Panckoucke, Paris, 752 pp. https://doi.org/10.5962/bhl.title.824
  11. Lamxay, V., Lanorsavanh, S., Chanthavong, K., Souvannakhoummane, K. & Bounphammy, S. (2021) A checklist of the vascular plants of Lao PDR version 1.0. Faculty of Natural Science, National University of Laos, Vientiane, 584 pp.
  12. Lim, C.K., Lee, K.E., Cho, H.S., Saysavanh, V. & Won, H. (2021) New records of flowering plants collected from the Phou Khao Khouay National Biodiversity Conservation Area for the flora of Laos. Korean Journal of Plant Taxonomy 51 (3): 305–318. https://doi.org/10.11110/kjpt.2021.51.3.305
  13. Linnaeus, C. (1753) Species plantarum 1. Salvius, Stockholm, 1200 pp. https://doi.org/10.5962/bhl.title.669
  14. Merrill, E.D. (1938) New or noteworthy Indo‑Chinese plants. Journal of the Arnold Arboretum 19 (1): 21–70. https://doi.org/10.5962/p.185378
  15. Nagahama, A., Tagane, S., Souladeth, P., Sengthong, A. & Yahara, T. (2019) Gentiana bolavenensis (Gentianaceae), a new species from Dong Hua Sao National Protected Area in southern Laos. Thai Forest Bulletin (Botany) 47 (2): 133–136. https://doi.org/10.20531/tfb.2019.47.2.02
  16. Newman, M., Ketphanh, S., Svengsuksa, B., Thomas, P., Sengdala, K., Lamxay, V. & Armstrong, K. (2007) A checklist of the vascular plants of Lao PDR. Royal Botanic Garden Edinburgh, Edinburgh, 394 pp.
  17. Sarawgi, A. & Choudhary, R.K. (2022) Canscora ciathula is not Canscora but rather belongs to the genus Phyllocyclus. Phytotaxa 575 (2): 184–186. https://doi.org/10.11646/phytotaxa.575.2.9
  18. Struwe, L. (2014) Classification and evolution of the family Gentianaceae. In: Rybczyński, J., Davey, M. & Mikuła, A. (Eds.) The Gentianaceae—volume 1: Characterization and ecology. Springer, Berlin, Heidelberg, pp. 13–35. https://doi.org/10.1007/978-3-642-54010-3_2
  19. Struwe, L. & Pringle, J.S. (2018) Gentianaceae. In: Kadereit, J.W. & Bittrich, V. (Eds.) The families and genera of vascular plants, Vol. 15. Springer, Cham, pp. 453–503. https://doi.org/10.1007/978-3-319-93605-5_6
  20. Thiv, M. (2003) A taxonomic revision of Canscora, Cracosna, Duplipetala, Hoppea, Microrphium, Phyllocyclus and Schinziella (Gentianaceae–Canscorinae). Blumea 48: 1–46. https://doi.org/10.3767/000651903X686042
  21. Tirel‑Roudet, C. (1972) Loganiaceae. In: Aubréville, A. & Leroy, J.-F. (Eds.) Flore du Cambodge, du Laos et du Viêtnam, Vol. 13. Muséum National D’Histoire Naturelle, Paris, pp. 3–89.
  22. Ubolcholaket, A. (1983) Preliminary study on Gentianaceae of Thailand. Thai Forest Bulletin (Botany) 14: 94–127.
  23. Ubolcholaket, A. (1987) Gentianaceae. In: Smitinand, T. & Larsen, K. (Eds.) Flora of Thailand, Vol. 5 (1). Chutima Press, Bangkok, pp. 72–92.
  24. Wong, K.M. & Sugumaran, M. (2012) Studies in Malesian Gentianaceae III: Cyrtophyllum reapplied to the Fagraea fragrans alliance. Gardens’ Bulletin Singapore 64 (2): 497–510.
  25. Wong, K.M. & Sugumaran, M. (2016) Studies in Malesian Gentianaceae, VII. A revision of Fagraea in the Malay Peninsula with five new species. Sandakania 21: 65–130.
  26. Yang, L.L., Li, H.L., Wei, L., Yang, T., Kuang, D.Y., Li, M.H., Liao, Y.Y., Chen, Z.D., Wu, H. & Zhang, S.Z. (2016) A supermatrix approach provides a comprehensive genus‑level phylogeny for Gentianales. Journal of Systematics and Evolution 54 (4): 400–415. https://doi.org/10.1111/jse.12192

How to Cite

Nuraliev, M.S., Averyanov, L.V. & Thiv, M. (2026) Duplipetala hexagona, a new generic record for Laos, and a key to Laotian Gentianaceae. Phytotaxa 748 (3): 258–268. https://doi.org/10.11646/phytotaxa.748.3.2