Research Article |
Corresponding author: Ping-Yuan Wang ( wpy@xtbg.org.cn ) Academic editor: Wen-Bin Yu
© 2019 Ping-Yuan Wang, De-Zhu Li.
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:
Wang P-Y, Li D-Z (2019) Dendrocalamus menghanensis (Poaceae, Bambusoideae), a new woody bamboo from Yunnan, China. In: Cai J, Yu W-B, Zhang T, Li D-Z (Eds) Revealing of the plant diversity in China’s biodiversity hotspots. PhytoKeys 130: 143-150. https://doi.org/10.3897/phytokeys.130.33948
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Dendrocalamus menghanensis P.Y.Wang & D.Z.Li, a new species of woody bamboos endemic to south Yunnan, China, is described and illustrated. The new species is morphologically similar to D. semiscandens and D. birmanicus but differs in having a reflexed culm sheath blade, 10 mm high culm sheath ligule, 1 mm high leaf sheath ligule, 4 florets and 1 glume.
Dendrocalamus, woody bamboo, Poaceae, Yunnan, taxonomy
The genus Dendrocalamus was described by
Most of the species of Dendrocalamus can be recognised by their thick-walled culms, swollen nodes reflexed culm sheath blade and aerial roots at the lower nodes. The species usually have white, blackish or light-brown hairs on the culm sheaths (
This new species resembles D. semiscandens (
All measurements of the new Dendrocalamus species were taken from dried herbarium specimens and living individuals at XTBG, Menglun, Mengla, Yunnan province. For morphological characterisation, vegetative parts of plant material were measured using the living plants and the reproductive parts were analysed under an automated digital microscope (ZEISS Smartzoom 5) linked with a computer in Xishuangbanna Station for Tropical Rainforest Ecosystem Studies of XTBG,
CHINA. Yunnan: Xishuangbanna, Menglun, 21°55.949'N, 101°15.139'E, 570 m alt., 18 November, 2010, P.Y. Wang C130022 (holotype: HITBC!; isotype: KUN!).
Dendrocalamus menghanensis is morphologically similar to D. semiscandens and D. birmanicus, but can be easily distinguished from them by having a reflexed culm sheath blade, 10 mm high culm sheath ligule, 1 mm high leaf sheath ligule, 4 florets and 1 glume.
Arborescent bamboo, perennials; rhizomes pachymorph, short necked. Culms apically pendulous, 8–12 m tall, 4–8 cm in diam.; culms terete, with a ring of white tomenta below sheath scars, internodes 20–40 cm long, wall 1–3.5 cm thick and almost solid at the base of culms; culm surface initially densely covered with white hairs and becoming glabrous later; culm sheaths deciduous, thickly leathery, 1/2 as long as the internodes, covered with dense brownish-black hairs, pale green initially, later becoming yellowish-brown with age; blades lanceolate, reflexed; auricles small inconspicuously lobed, oral setae absent; ligules ca. 10 mm high, dentate. Branching from lower nodes ca. 0.5–1.0 m above ground, branches several, usually subequal, sometimes 1 dominant; ultimate branchlets with 10–16 leaves, usually 12 leaves. Foliage leaves lanceolate, 11–30(-35) cm × 2–4.5(-6) cm, adaxial surface green and glabrous, abaxial surface pale green and pubescent, margins serrulate, secondary veins 7–11 pairs, usually 10 pairs, petioles 2–5 mm; leaf sheaths initially white hairy and later glabrous; auricles inconspicuous, ligules ca. 1 mm high, entire. Flowering branches pendulous, leafless, with clusters of 3 to 15(-60) pseudo-spikelets at each node; clusters 1–3.5 cm in diam.; pseudo-spikelets ovate-lanceolate, pale green, apically acute and light purple, 12–16 × 3–4 mm; fertile florets usually 4 per pseudo-spikelet; glumes 1, broadly ovate, 5–7 × 4–6 mm, margins ciliate at upper half; lemma ovate, 8–12 × 4–7 mm, pubescent, many-veined, apex mucronate, margins ciliate; palea oblanceolate, 2-keeled, 7–11 × 1–2 mm, keels and margins long ciliate; lodicules absent; stamens 6, ca. 6 mm long, ovary ovoid, pistil ca. 16 mm long, anthers yellow, filaments free, ca. 14 mm long; stigma 1, purple, plumose. Fruit unknown.
Dendrocalamus menghangensis is only known from Menghan Township, Jinghong, Yunnan, China.
As a great many forests have been destroyed by local people in the last 30 years, we did not find the new species at the locality where it was introduced. Further investigation is required to find more distribution localities and determine the conservation status of the new species. At present, we consider it as DD (Deficient Data) according to the IUCN parameters (
The specific epithet refers to the original place of the new species, i.e. Menghan Town, Xishuangbanna, south Yunnan, China.
Shooting from July to October and flowering from December to May of the next year.
CHINA. Yunnan, Xishuangbanna, Menglun, 21°55.949'N, 101°15.139'E, 570 m alt., 7 December, 2010, P.Y. Wang C130051 (paratype: HITBC!, KUN!)
Dendrocalamus menghanensis is morphologically similar to D. semiscandens and D. birmanicus. However, the new species differs from them by having a reflexed culm sheath blade, 10 mm high culm sheath ligule, 1 mm high leaf sheath ligule, 4 florets and 1 glume. The major differences amongst these species are listed in Table
Morphological differences amongst Dendrocalamus menghanensis, D. semiscandens and D. birmanicus.
Characters | D. menghanensis | D. semiscandens | D. birmanicus |
---|---|---|---|
Diameter of culm | 4–8 cm | 6–15 cm | ca. 8 cm |
Culm sheath blade | reflexed | erect | reflexed |
Number of florets | 4 | 4–5 | 2–3 |
Culm sheath | covered with dense brownish-black hairs | covered with dark brown hairs | covered with dark brown hairs |
Culm sheath ligule | 10 mm | 1 mm | 3–4 mm |
Leaf sheath ligule | 1 mm | 3–5 mm | 1 mm |
Glume | 1 | 1–3 | 2 |
Anther | 6 mm, yellow | 3.7 mm, yellow, anther tip purple | 3–4 mm |
This study was supported by grants from the National Natural Science Foundation of China (31700560) and Natural Science Foundation of Yunnan Province (2018FB043). We thank Dr. Wen-Bin Yu from Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences for improving the manuscript. We also appreciate the Xishuangbanna Station for Tropical Rainforest Ecosystem Studies and Herbarium of Xishuangbanna Tropical Botanical Garden (HITBC) for their support during the examination of specimens.