A checklist of Burmanniaceae in Eastern Indochina with a new record from Vietnam, Burmannia itoana Author Nuraliev, Maxim S. 0000-0001-8291-2633 Joint Russian-Vietnamese Tropical Scientific and Technological Center, Cau Giay, Hanoi, Vietnam. & Department of Higher Plants, Biological Faculty, M. V. Lomonosov Moscow State University, 1, 12, Leninskie Gory, 119234 Moscow, Russia. & max. nuraliev @ gmail. com; https: // orcid. org / 0000 - 0001 - 8291 - 2633 max.nuraliev@gmail.com Author Yudina, Sophia V. 0000-0003-3053-8357 Joint Russian-Vietnamese Tropical Scientific and Technological Center, Cau Giay, Hanoi, Vietnam. & Department of Higher Plants, Biological Faculty, M. V. Lomonosov Moscow State University, 1, 12, Leninskie Gory, 119234 Moscow, Russia. & Institute for Information Transmission Problems, 127051, Moscow, Russia. & yudina. sophia @ gmail. com; https: // orcid. org / 0000 - 0003 - 3053 - 8357 yudina.sophia@gmail.com Author Truong, Ba Vuong 0000-0003-3452-8455 Institute of Tropical Biology, Vietnam Academy of Science and Technology, 85 Tran Quoc Toan St., Distr. 3, Ho Chi Minh City, Vietnam. Faculty of Biology, Shenzhen MSU-BIT University, 518172, Shenzhen, China. & bavuong 2019 @ yahoo. com; https: // orcid. org / 0000 - 0003 - 3452 - 8455 bavuong2019@yahoo.com Author Dang, Van Son 0000-0001-8681-4141 Institute of Tropical Biology, Vietnam Academy of Science and Technology, 85 Tran Quoc Toan St., Distr. 3, Ho Chi Minh City, Vietnam. Faculty of Biology, Shenzhen MSU-BIT University, 518172, Shenzhen, China. & dvsonitb @ gmail. com; https: // orcid. org / 0000 - 0001 - 8681 - 4141 dvsonitb@gmail.com Author Kopylov-Guskov, Yury O. 0000-0002-3051-8789 Joint Russian-Vietnamese Tropical Scientific and Technological Center, Cau Giay, Hanoi, Vietnam. & Department of Higher Plants, Biological Faculty, M. V. Lomonosov Moscow State University, 1, 12, Leninskie Gory, 119234 Moscow, Russia. & yurez-kg @ yandex. ru; https: // orcid. org / 0000 - 0002 - 3051 - 8789 yurez-kg@yandex.ru Author Lyskov, Dmitry F. 0000-0003-0818-1662 Joint Russian-Vietnamese Tropical Scientific and Technological Center, Cau Giay, Hanoi, Vietnam. & Department of Higher Plants, Biological Faculty, M. V. Lomonosov Moscow State University, 1, 12, Leninskie Gory, 119234 Moscow, Russia. & df. lyskov @ yandex. ru; https: // orcid. org / 0000 - 0003 - 0818 - 1662 df.lyskov@yandex.ru Author Kuznetsov, Andrey N. 0000-0001-5595-1039 Joint Russian-Vietnamese Tropical Scientific and Technological Center, Cau Giay, Hanoi, Vietnam. & A. N. Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences, Leninsky 33, Moscow, Russia. & forestkuz @ mail. ru; https: // orcid. org / 0000 - 0001 - 5595 - 1039 forestkuz@mail.ru Author Kuznetsova, Svetlana P. 0000-0002-7610-5058 Joint Russian-Vietnamese Tropical Scientific and Technological Center, Cau Giay, Hanoi, Vietnam. & tropcenterhanoi @ mail. ru; https: // orcid. org / 0000 - 0002 - 7610 - 5058 tropcenterhanoi@mail.ru Author Zhang, Dianxiang 0000-0001-6549-8872 Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China. & dx-zhang @ scbg. ac. cn; https: // orcid. org / 0000 - 0001 - 6549 - 8872 dx-zhang@scbg.ac.cn text Phytotaxa 2022 2022-04-27 544 1 61 70 journal article 55797 10.11646/phytotaxa.544.1.5 f31786c6-80cb-48a4-aea8-e4e15772e82e 1179-3163 6501413 Key to the species of Burmannia in Cambodia , Laos and Vietnam Partly based on: Gagnepain (1908) , Zhang (1999) , Wu et al. (2010) and species protologues. Terminology of flower structure follows Yudina et al. (2022) . 1. Plant chlorophyllous (with green leaves and stem)............................................................................................................................2 - Plant apparently achlorophyllous (lacking green coloration in all plant parts)..................................................................................8 2. Plant robust, perennial, with at least some leaves longer than 3 cm and wider than 0.3 cm .............................................. B. disticha - Plant delicate, annual, with leaves up to 3 cm long and 0.3 cm wide ................................................................................................3 3. Both outer and inner tepal lobes with double margins ...................................................................................................... B. coelestis - Outer tepal lobes with single or double margins; inner tepal lobes with single margins ...................................................................4 4. Perianth wings narrow, ca. 0.5–0.8 mm wide; outer tepal lobes with single margins.......................................... B. cochinchinensis - Perianth wings pronounced, at least 1 mm wide (usually 2–3 mm wide); outer tepal lobes with single or double margins.............5 5. Outer tepal lobes with single or double margins (single margins only in China and India ); inner tepal lobes ca. 0.4–1.5 mm long (in Eastern Indochina, ca. 1–1.5 mm long) ..................................................................................................................... B. chinensis - Outer tepal lobes with single margins; inner tepal lobes ca. 0.5–0.8 mm long..................................................................................6 6. Flower 10–13 mm long; outer tepal lobes ca. (1) 1.8–2.2 mm long ............................................................................ B. subcoelestis - Flower 6–11 mm long; outer tepal lobes ca. 1–1.5 mm long .............................................................................................................7 7. Outer tepal lobes fleshy; inner tepal lobes oblanceolate or spatulate............................................................................... B. luteoalba - Outer tepal lobes thin; inner tepal lobes lanceolate.............................................................................................................. B. pusilla 8(1). Whole plant bluish..............................................................................................................................................................................9 - Whole plant whitish..........................................................................................................................................................................12 9. Perianth wings prominent, 1–2 mm wide.............................................................................................................................. B. itoana - Perianth wings narrow (often rib-like), up to 0.8 mm wide .............................................................................................................10 10. Perianth wings rib-like to semi-elliptic, 0.2–0.8 mm wide; outer tepal lobes ca. 1 mm long ........................................... B. wallichii - Perianth wings rib-like; outer tepal lobes 2.5–4 mm long................................................................................................................11 11. Flower larger (outer tepal lobes 3–4 mm × 1.5–2 mm , inner tepal lobes 2 mm × 1.5 mm , ovary 2.5–3 mm long); outer tepal lobes at apex slightly attenuate and obtuse................................................................................................................................. B. coerulea - Flower smaller (outer tepal lobes 2.5–3 mm × 1.25–1.5 mm , inner tepal lobes 1 mm × 0.8 mm , ovary 2–2.5 mm long); outer tepal lobes at apex attenuate into long acute caudate tip ca. 1 mm long.............................................................................. B. unguiculata 12(8). Inflorescence dense (usually head-like), with 3–13 flowers; flower wingless or with rib-like perianth wings........... B. championii - Inflorescence lax (axes usually apparently elongated), with up to 5 (rarely 9) flowers; perianth wings prominent or rarely rib-like ..........................................................................................................................................................................................................13 13. Outer tepal lobes broadly oblong to broadly quadrangular, with emarginate apex; inner tepal lobes absent .................... B. oblonga - Outer tepal lobes ovate, triangular or oblong, with acuminate, obtuse, rounded or slightly retuse apex; inner tepal lobes absent or present...............................................................................................................................................................................................14 14. Floral tube 1.5–2.5 mm long; outer tepal lobes 0.5–1.2 mm long; inner tepal lobes present ........................................ B. nepalensis - Floral tube 3.5–5 mm long; outer tepal lobes 1–1.8 mm long; inner tepal lobes absent or present................................. B. lutescens