Research Article |
Corresponding author: Yun-Hong Tan ( tyh@xtbg.org.cn ) Academic editor: Xiao-Hua Jin
© 2018 Hong-Bo Ding, Yang Bin, Shi-Shun Zhou, Ren Li, Mya Bhone Maw, Win Maung Kyaw, Yun-Hong Tan.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Ding H-B, Bin Y, Zhou S-S, Li R, Maw MB, Kyaw WM, Tan Y-H (2018) Hedychium putaoense (Zingiberaceae), a new species from Putao, Kachin State, Northern Myanmar. In: Jin X-H, Shui Y-M, Tan Y-H, Kang M (Eds) Plant diversity in Southeast Asia. PhytoKeys 94: 51-57. https://doi.org/10.3897/phytokeys.94.22065
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Hedychium putaoense Y.H. Tan & H.B. Ding, a new species of Zingiberaceae from Putao, Kachin state, Northern Myanmar, is described and illustrated. It is similar to H. densiflorum Wall. and H. longipedunculatum A.R.K. Sastry & D.M. Verma, but differs by its very small bract (4–6 × 2.5–3 mm vs. 18–19 × 5–5.5 mm and ca. 11 × 7 mm, respectively), semicircle and dark red bracteole, orange flower and broadly falcate to lanceolate lateral staminodes.
Hedychium , Myanmar, Taxonomy, Morphology, Zingiberaceae
The pantropical Zingiberaceae is the largest family in the monophyletic order Zingiberales with 53 genera and more than 1377 species (
Several new species of Hedychium have been described in the last few decades (
From April to May in 2017, a team from the Xishuangbanna Tropical Botanical Garden (XTBG) in collaboration with the Forest Research Institute of Myanmar, conducted field work in Northern Myanmar to survey plant diversity. During field work, some interesting specimens of Hedychium were found in Putao, Kachin state. Based on a detailed examination of the morphological characteristics of the collected material and those of the closely related similar species, the authors have arrived at the conclusion that the specimens of Hedychium collected in Myanmar belong to a species new to science, which are described and illustrated herein.
Measurements and morphological character assessments of the new species Hedychium putaoense have been examined based on fresh materials and dried specimens. It has been compared with the morphologically similar species H. densiflorum, H. longipedunculatum, with affinities inferred using descriptions, type specimens and other herbarium specimens (
Hedychium putaoense Y.H. Tan & H.B. Ding is morphologically similar to H. densiflorum Wall. and H. longipedunculatum A.R.K. Sastry & D.M. Verma, but it can be easily distinguished by its very small bract (4–6 × 2.5–3 mm vs. 18–19 × 5–5.5 mm and ca. 11 × 7 mm, respectively) and bracteole (2–2.5 × 3–3.5 mm vs. ca. 9 × 2 mm and ca. 6 × 4 mm, respectively), orange flower and broadly falcate to lanceolate lateral staminodes.
MYANMAR. Kachin State: Putao District, the top of the mountain from Masabu village to Namti village. Epiphytic herbs in tropical montane forests, 97°17'42"E, 27°25'29"N. 1700 m a.s.l., 13 May 2017, flowering, Myanmar Exped. M1724 (holotype: HITBC!; isotypes: HITBC!)
Epiphytic, sometimes terrestrial, perennial rhizomatous herbs, light greyish-green externally. Leafy shoot 20–50 cm high, slanting with erect inflorescence. Leaves 4, spreading, sessile, upper petioled; petiole 2–10 mm long; ligule ca. 8–19 mm long, apex obtuse, glabrous, membranous, translucent, reddish brown when fresh, yellowish brown when dry, closely appressed to the stem; lamina 13–23 × 3–7 cm, lanceolate, dark green above, pale green below, or sometimes light purple-tinged below, glabrous; margin undulate, membranous, non-ciliate; apex narrowly caudate, twisted, base attenuate. Inflorescences 7–10 cm long, cylindrical, dense, erect, rachis glabrescent. Bracts 4–6 × 2.5–3.0 mm, ovate, purplish-red, glabrous, convolute, margin ciliate, membranous, tip acute, cincinnus 1-flowered. Bracteoles 2.0–2.5 × 3.0–3.5 mm, semicircular, dark red, glabrous, membranous, acute at tip, margin ciliate. Flower 2.8–3.9 cm long, small, orange, nearly entire inflorescence open at a time, ascending. Calyx 1.2–1.4 cm long, 2.0–2.5 mm wide at mouth, tubular, pale light red, densely villous, tufted hairs at tip, membranous, upper half inflated, lower part closely appressed to corolla tube, unilaterally split up to ca. 5 mm depth. Corolla tube 10–13 mm long, creamy yellow, glabrous, tube intensely curved towards tip about 90° to 180°. Corolla lobes 10–16 × 1–2 mm linear-lanceolate, red, membranous, glabrous. Lateral staminodes 11–13 × 3–4 mm, broadly falcate to lanceolate, clawed towards base, orange, spreading on flower, obtuse at tip, intensely reflexed back. Labellum 12–14 × 4–7 mm, widely obovate, orange, spreading on flower, base cuneate, sinus ca. 2–3 mm deep, lobes oblong, obtuse at tip. Stamen 1.4–1.7 cm long. Filament 1.1–1.2 cm long, ca. 2 mm wide at base, orange, creamy yellow towards base, intensely curved towards tip about 180°. Anthers ca. 5 × 2 mm, oblong, orange, split opens from top to bottom, attached with the filament at ca. 1 mm above from base, thecae parallel with the filament; connective red, glabrous, non-crested. Ovary ca. 2.5 mm diameter, sub-globose, densely villous. Style filiform, creamy white, glabrous, dark red-tinged towards stigma. Stigma ca. 0.5 mm wide, dark red, cup-shaped, mouth margin ciliate, ca. 1 mm exserted from the anther. Epigynous glands 2, ca. 1 mm long, oblong, orange. Fruit unknown.
Hedychium putaoense Y.H. Tan & H.B. Ding. a–b Habit c–d Inflorescence e–f Front and lateral view of flower g Bract h Bracteole i Calyx j–k Corolla lobe l–m Lateral staminodes n Labellum o Corolla tube with anther and calyx p Ovary with pistil and glands. Photographed by Y.H. Tan & H.B. Ding.
Flowering from May to July.
This new species is known to grow at the top of the mountain from Masabu village to Namti village, Putao District, Kachin State, where it grows epiphytically on the trees of tropical montane forests at an elevation of ca. 1400–1800 m.
The species is named after the type locality, Putao county, in Kachin State, Myanmar.
Hedychium putaoense Y.H. Tan & H.B. Ding shares certain characteristics with H. densiflorum (
Comparison of key morphological characters of Hedychium putaoense, H. densiflorum, and H. longipedunculatum.
Attributes | H. putaoense | H. densiflorum | H. longipedunculatum |
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Ligule | 8-19 mm long apex obtuse | 10–11 mm long apex obtuse | 15–20 mm long notched at tip |
Lamina | 13–23 × 3–7 cm lanceolate | 28–31 × 4.5–5.8 cm elliptic | 15–23 × 6–10 cm broadly elliptic |
Inflorescence | 7–10 cm long rachis glabrescent | 11–17 cm long rachis glabrescent | 9–20 cm long rachis hairy |
Bract | 4–6 × 2.5–3 mm ovate, purplish red | 18–19 × 5–5.5 mm elliptic, pale green | ca. 11 × 7 mm triangular, pinkish-red |
Bracteole | 2.0–2.5 × 3–3.5 mm semicircle, dark red | 8–10 × ca. 2 mm tubular, pale green | ca. 6 × 4 mm ovate, red |
Flower | 2.8–3.9 cm long, orange | 2.8–3 cm long, orange-red | 3–3.3 cm long, creamy yellow |
Calyx | 12–14 mm long, pale light red | 13–14 mm long, white | ca. 11 mm long, pale yellow |
Corolla tube | 10–13 mm long creamy yellow curved towards tip about 90° to 180° | 18–19 mm long white, orange-red towards tip bent to one side towards tip | ca. 11 mm long creamy yellow with pale red erect |
Corolla lobes | 10–16 × 1–2 mm linear-lanceolate, red | 12–13 × ca. 3 mm elliptic, yellow | ca. 16 × 3 mm linear-lanceolate, creamy yellow |
Labellum | 12–14 × 4–7 mm, widely obovate, orange, sinus 2–3 mm deep | 9–10 × ca. 8 mm, widely obovate, orange-red, sinus 3.5–4 mm deep | ca. 15 × 6 mm, spatulate, creamy yellow, sinus ca. 1 mm deep |
Lateral staminodes |
11–13 × 3–4 mm broadly falcate to lanceolate, orange | 8–8.5 × 5 mm elliptic, orange-red | 17 × 7 mm spatulate, creamy-yellow |
Stamen | 1.4–1.7cm long | 1.4–1.5 cm long | ca. 2.2 cm long |
Filament | 11–12 mm long, orange intensely curved towards tip about 180° | 8–8.5 mm long, orange-red straight | ca. 15 mm long, yellow erect |
Anther | ca. 5 × 2 mm, orange | ca. 6.5 × 2.5 mm, orange-red | ca. 7 mm long, bright-yellow |
Connective | red | orange-red | bright-yellow |
Ovary | ca. 2.5 mm diameter densely villous | ca. 2 mm diameter glabrous | ca. 3 mm diameter densely villous |
Stigma | ca. 0.5 mm wide, dark red | ca. 1 mm wide, yellow | ca. 1 mm wide, green |
Style | filiform, creamy white dark red tinged towards stigma | filiform, white yellow tinged towards stigma | filiform, white green tinged towards stigma |
The authors are grateful to the Forest Research Institute of Myanmar for permission to conduct this study in Northern Myanmar and for their support and collaboration. We are grateful to Myint Zaw for his kind help in the field work. We are also grateful to Yuwen-Cui for editing the photographs. This work was financially supported by a project of the Southeast Asia biodiversity research institute, Chinese Academy of Sciences (Y4ZK111B01).