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Dendrocalamus menghanensis (Poaceae, Bambusoideae), a new woody bamboo from Yunnan, China
expand article infoPing-Yuan Wang§, De-Zhu Li|
‡ Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, China
§ University of Chinese Academy of Sciences, Beijing, China
| Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China
Open Access

Abstract

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.

Keywords

Dendrocalamus, woody bamboo, Poaceae, Yunnan, taxonomy

Introduction

The genus Dendrocalamus was described by Nees von Esenbeck (1835) and currently comprises of more than 50 species in tropical and subtropical regions of Asia (Ohrnberger 1999, Bamboo Phylogeny Group 2012). Several new species in this genus have been continuously described in recent years (Yang et al. 2016, Wang et al. 2016, Nguyen et al. 2017a, 2017b). There are about 30 species of Dendrocalamus distributed in China (including new species described in recent years) (Li et al. 2006). It is a typical paleotropical woody bamboo genus belonging to the subtribe Bambusinae Presl (1830) of tribe Bambuseae Kunth ex Dumortier (1829). Within this subtribe, the three major genera are Bambusa (von Schreber 1789), Dendrocalamus and Gigantochloa Kurz ex Munro (1868). They formed a clade known as the BDG complex (Goh et al. 2010, 2013), also named “core Bambusinae”, but the long-standing problems for taxonomic delimitation and evolutionary relationships within the BDG complex have not been satisfactorily resolved (Goh 2012, Chokthaweepanich 2014, Zhou et al. 2017).

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 (Dransfield 1980). Compared to Dendrocalamus, it is easy to classify the Bambusa species by the erect culm sheath blade and conspicuous auricles and Gigantochloa by connate filaments. While checking the bamboos cultivated in Xishuangbanna Tropical Botanical Garden (XTBG), Chinese Academy of Sciences (CAS), we discovered an extraordinary Dendrocalamus species. The floret of this species has no lodicule, one plumose stigma, six stamens and completely separate filaments, indicating that it belongs to Dendrocalamus rather than to Gigantochloa or Bambusa (Li and Hsueh 1988a, 1988b, Dransfield and Widjaja 1995, McClure 1966, Wong 1995, Li et al. 2006, Clayton et al. 2008, Sungkaew 2008).

This new species resembles D. semiscandens (Li and Hsueh 1989) and D. birmanicus Camus (1932) in some morphological characters as discussed below (see Table 1). It was introduced in XTBG from Menghan Township, Jinghong, Yunnan, China in 1980.

Material and methods

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, CAS. The morphological terminology followed McClure (1966).

Taxonomy

Dendrocalamus menghanensis P.Y.Wang & D.Z.Li, sp. nov. “勐罕龙竹” (Meng Han Long Zhu)

Figures 1, 2

Type

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!).

Diagnosis

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.

Figure 1. 

Dendrocalamus menghanensis P.Y. Wang & D.Z. Li. A Culm sheath (abaxial view) B ultimate branchlet with leaves C portion of young culm with culm sheath D portion of flowering branch E pseudo-spikelet F pistil G stamen H glume I lemma J Palea. Drawn from the holotype.

Figure 2. 

Dendrocalamus menghanensis P.Y.Wang & D.Z.Li. A Clump B portion of young culm with culm sheath C new shoot D flowering branches E glume F lemma G palea H floret I pistil J ovary.

Description

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.

Distribution

Dendrocalamus menghangensis is only known from Menghan Township, Jinghong, Yunnan, China.

Conservation status

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 (IUCN 2012).

Etymology

The specific epithet refers to the original place of the new species, i.e. Menghan Town, Xishuangbanna, south Yunnan, China.

Phenology

Shooting from July to October and flowering from December to May of the next year.

Additional specimens examined (paratype)

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!)

Discussion

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 1. This new species is only found in Xishuangbanna which is located in one of the world’s biodiversity hotspots (Indo-Burma) (Myers et al. 2000). Many forests have been destroyed because of the plantation of rubber trees in this region in the past 30 years. Many species may become extinct before we know that they exist in Xishuangbanna. More field investigations need to be conducted in this region in future.

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

Acknowledgements

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.

References

  • Bamboo Phylogeny Group [BPG] (2012) An updated tribal and subtribal classification of the bamboos (Poaceae: Bambusoideae). In: Gielis J, Potters G (Eds) Proceedings of the 9th world bamboo congress, 10–12 Apr 2012. Antwerp, Belgium, 3–27.
  • Camus A (1932) Dendrocalamus birmanicus, bambou nouveau de Birmanie. In: Bulletin du Muséum National d’Histoire Naturelle, sér 2, 4(8): 1044–1045.
  • Chokthaweepanich H (2014) Phylogenetics and evolution of the paleotropical woody bamboos (Poaceae: Bambusoideae: Bambuseae). Iowa State University, 213 pp.
  • Dransfield S (1980) Bamboo taxonomy in the Indo-Malesian Region. In: Lesserd G, Chouinard A (Eds) Bamboo research in Asia. Proceedings of a workshop, Singapore, 28–30 May, IDRC, Ottawa, IUFRO, 121–130.
  • Dransfield S, Widjaja EA (1995) Plant resources of South-East Asia 7: bamboos. Backhuys Publishers, Leiden, 189 pp.
  • Dumortier BCJ (1829) Analyse des familles de plantes: avec l’indication des principaux genres qui s’y rattachent. Impr. de J. Casterman, Ainé, Tournay, 104 pp. https://doi.org/10.5962/bhl.title.443
  • Goh WL (2012) Molecular studies of Southeast Asian woody bamboos (Poaceae: Bambusoideae: Bambuseae): perspectives in reticulate evolution, phylogenetic relationships and classification. University of Malaya, Kuala Lumpur, 159 pp.
  • Goh WL, Chandran S, Lin RS, Xia NH, Wong KM (2010) Phylogenetic relationships among Southeast Asian climbing bamboos (Poaceae: Bambusoideae) and the Bambusa complex. Biochemical Systematics and Ecology 38(4): 764–773. https://doi.org/10.1016/j.bse.2010.07.006
  • Goh WL, Chandran S, Franklin DC, Isagi Y, Koshy KC, Sungkaew S, Yang HQ, Xia NH, Wong KM (2013) Multi-gene region phylogenetic analyses suggest reticulate evolution and a clade of Australian origin among paleotropical woody bamboos (Poaceae: Bambusoideae: Bambuseae). Plant Systematics and Evolution 299(1): 239–257. https://doi.org/10.1007/s00606-012-0718-1
  • IUCN (2012) IUCN Red List categories and criteria: version 3.1. Second edition. IUCN Species Survival Commission, IUCN, Gland and Cambridge, 32 pp.
  • Li DZ, Hsueh C (1988a) A study on the genus Dendrocalamus Nees from China (I). Journal of Bamboo Research 7(3): 1–19.
  • Li DZ, Hsueh C (1988b) A study on the genus Dendrocalamus Nees from China (II). Journal of Bamboo Research 7(4): 1–19.
  • Li DZ, Hsueh C (1989) A study on the genus Dendrocalamus Nees from China (III). Journal of Bamboo Research 8(1): 25–43.
  • Li DZ, Wang ZP, Zhu ZD, Xia NH, Jia LZ, Guo ZH, Yang GY, Stapleton CMA (2006) Bambuseae. In: Wu ZY, Raven PH, Hong DY (Eds) Flora of China Vol. 22. Science Press, Beijing & Missouri Botanical Garden Press, St. Louis, 7–180.
  • Myers N, Mittermeier RA, Mittermeier CG, da Fonseca GAB, Kent J (2000) Biodiversity hotspots for conservation priorities. Nature 403(6772): 853–858. https://doi.org/10.1038/35002501
  • Nees von Esenbeck CGD (1835) Bambuseae brasilienses. Linnaea 9(4): 461–494.
  • Nguyen HN, Nguyen VT, Nguyen AD, Vien N, Tien PQ, Tran VT (2017a) Dendrocalamus dienbienensis (Poaceae: Bambusoideae), a new species from Northern Vietnam. Phytotaxa 327(3): 290–296. https://doi.org/10.11646/phytotaxa.327.3.9
  • Nguyen HN, Nguyen VT, Le VL, Tran VT, Nguyen V (2017b) Dendrocalamus phuthoensis (Poaceae: Bambusoideae), a new species from Phu Tho province, Vietnam. Phytotaxa 296(3): 274–280. https://doi.org/10.11646/phytotaxa.296.3.6
  • Ohrnberger D (1999) The Bamboos of the World. Elsevier Science B. V., Amsterdam, the Netherlands.
  • Presl JS (1830) Subtribus II.Bambusaceae. Reliquiae Haenkeanae 1(4–5): 256.
  • Sungkaew S (2008) Taxonomy and systematics of Dendrocalamus (Bambuseae: Poaceae). University of Dublin, Trinity College, Ireland, 293 pp.
  • von Schreber JCD (1789) Genera plantarum. ed. 8 vol. 1. Frankfurt am Main, 379 pp.
  • Wang PY, Zhang YX, Li DZ, Liu WJ (2016) Dendrocalamus jinghongensis (Poaceae, Bambusoideae), another new woody bamboo from Yunnan, China. Phytotaxa 272(3): 209–214. https://doi.org/10.11646/phytotaxa.272.3.5
  • Wong KM (1995) The bamboos of Peninsular Malaysia. Malindo Printers Sdn. Bhd. , Shah Alam, Selangor, 200 pp.
  • Yang HQ, Xie N, Sun M, Xu T, Li DZ (2016) Dendrocalamus atroviridis (Poaceae: Bambusoideae, Bambuseae), a new species from Southwest China. Phytotaxa 243(2): 170–174. https://doi.org/10.11646/phytotaxa.243.2.7
  • Zhou MY, Zhang YX, Haevermans T, Li DZ (2017) Towards a complete generic-level plastid phylogeny of the paleotropical woody bamboos (Poaceae: Bambusoideae). Taxon 66(3): 539–553. https://doi.org/10.12705/663.2